Zipper tape and container with zipper tape

Abstract

A zip fastener tape (3) is provided with: first resin portions (41, 51) that are formed from a first resin composition having a first polyester resin as a main component, and include a pair of base section strips (a first base section strip (42) and a second base section strip (52)) and engaging sections (a male engaging section (43) and a female engaging section (53)), the engaging section being capable of engaging each other, and each protruding out from mutually opposing surfaces of the pair of base section strips; and second resin portions (44, 54) that are formed from a second resin composition having a second polyester resin as a main component, and that cover each of the surfaces opposite the engaging sections of the pair of base section strips. The first resin composition contains a first modifying agent at a first content ratio. The second resin composition either contains the first modifying agent at a second content ratio, which is lower than the first content ratio, or does not contain the first modifying agent.

Description

[Technical field]

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

[0002] 2. Description of the Related Art A zippered bag having a zipper member welded thereto is known (see, for example, Patent Document 1). The zipper member described in Patent Document 1 consists of a female zipper tape welded to one inner surface of a zippered bag, and a male zipper tape welded to the other inner surface. The zipper member can be welded to a heat-sealable polyethylene terephthalate (HS-PET) resin layer of the bag, and is made of a mixed resin obtained by mixing polyethylene terephthalate (PET) resin with other resins in order to provide flexibility for the zipper to function. Specifically, Patent Document 1 lists a mixed resin of 30-80% by weight of PET resin and 20-70% by weight of polyester-based thermoplastic elastomer as a first mixed resin forming the zipper member, and lists a mixed resin of 40-80% by weight of PET resin and 20-60% by weight of low-density polyethylene (LDPE) resin or linear low-density polyethylene (LLDPE) resin to which a compatibilizer has been added as a second mixed resin forming the zipper member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-52551 A Summary of the Invention [Problem to be solved by the invention]

[0004] As in the example of Patent Document 1, by setting the content of PET resin in the resin composition to a predetermined ratio or less, flexibility suitable for a zipper can be provided. However, in this case, it is difficult to obtain sufficient seal strength between the zipper member and the HS-PET sealant. Increasing the content of PET resin in the resin composition increases the seal strength between the zipper member and the HS-PET sealant, but it becomes difficult to obtain flexibility suitable for a zipper.

[0005] An object of the present invention is to provide a zipper tape and a container with a zipper tape that are capable of obtaining sufficient seal strength with an HS-PET sealant while having flexibility suitable for a zipper. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided a zipper tape comprising: a first resin portion formed from a first resin composition containing a first polyester resin as a main component, the first resin portion including a pair of base strips and engaging portions protruding from opposing surfaces of the pair of base strips and capable of engaging with each other; and a second resin portion formed from a second resin composition containing a second polyester resin as a main component, the second resin portion covering each of the surfaces of the pair of base strips opposite the engaging portions, the first resin composition containing a first modifier in a first content, and the second resin composition containing the first modifier in a second content lower than the first content, or not containing the first modifier.

[0007] According to another aspect of the present invention, there is provided a container with a zipper tape, comprising the above zipper tape and a container body to which the zipper tape is welded. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a plan view showing a container with a zipper tape according to one embodiment of the present invention. [Diagram 2] 2 is a cross-sectional view of the zipper tape container shown in FIG. 1 taken along line II-II. [Diagram 3]FIG. 11 is a diagram showing the angle of the male engaging portion and the dimensions of the second member in the container with zipper tape according to the embodiment. [Figure 4] 1 is a graph showing the results of measuring the tensile modulus of elasticity of a plurality of test pieces formed from a resin composition containing a modifier in one embodiment of the present invention. [Diagram 5] 1 is a graph showing the measurement results of the tensile modulus of a resin composition containing an ethylene-methacrylic acid-acrylic acid ester copolymer in one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. In this specification and drawings, elements having substantially the same functions and configurations are denoted by the same reference numerals and redundant explanations will be omitted. In this specification, the main component means the component that is the most abundant among the components of the resin composition. More specifically, when the resin composition is composed of n components (n is an integer of 2 or more), the main component is a component that is contained in an amount of 100 / n% or more, preferably 100 / n x 1.2 times % or more. The main component can be determined by analysis using infrared spectroscopy, NMR, DSC, or the like. Note that the resin composition may contain impurities within a range that does not impair the effects of the present invention.

[0010] The container 1 with a zipper tape according to this embodiment will be described below. Fig. 1 is a plan view showing a container with a zipper tape 1. Fig. 2 is a view showing a cross section of the container with a zipper tape 1 taken along line II-II shown in Fig. 1. As shown in FIGS. 1 and 2, a container 1 with a zipper tape includes a container body 2 which is a bag having a first surface 21 and a second surface 22 opposed to each other, and a zipper tape 3.

[0011] [Container body configuration] The container body 2 is composed of a film 20. The film 20 has at least one layer formed of, for example, a thermoplastic resin. The film 20 may include layers formed of low density polyethylene (LDPE), linear low density polyethylene (LLDPE), or polypropylene (PP). The PP may be homopolypropylene (HPP), random polypropylene (RPP), or block polypropylene (BPP). When the film 20 is a multilayer film, the surface substrate may be biaxially oriented polypropylene (OPP), biaxially oriented polyethylene terephthalate (OPET), or biaxially oriented nylon (ONy). The film 20 may also include a layer of an inorganic material formed by aluminum deposition or lamination of aluminum foil. In this embodiment, the portions of the first surface 21 and the second surface 22 to which the zipper tape 3 is welded are sealant layers 211, 221 formed of a resin composition mainly composed of heat-sealable polyethylene terephthalate (HS-PET). That is, the container body 2 has the sealant layers 211, 221 formed of a resin composition mainly composed of heat-sealable PET. The material of the film 20 is not limited to resin derived from fossil fuels, but may be environmentally friendly bioplastic, or a mixture of fossil fuel-derived resin and bioplastic.

[0012] In this embodiment, two sheets of film 20 are joined to each other at bottom seal portion 23 and side seal portion 24 to form a bag having first surface 21 and second surface 22. In another embodiment, one sheet of film 20 may be folded back at a portion corresponding to side seal portion 24 to form a bag having first surface 21 and second surface 22. Alternatively, a portion where film 20 is folded inward, a so-called gusset, may be formed at a portion corresponding to bottom seal portion 23 or side seal portion 24 in the example of FIG. 1. In this case, the gusset may be formed by film 20, or may be formed by another film joined to film 20. The zipper tape-attached container 1 may also be a standing pouch that can be placed upright by forming a gusset at the bottom.

[0013] In this embodiment, the bottom seal portion 23 and the side seal portion 24 are formed, but the top seal portion is not formed, so that the opening 11 of the zipper tape-attached container 1 is formed. In another embodiment, the top seal portion may be formed in addition to the bottom seal portion 23 and the side seal portion 24, and the opening 11 may be formed later in the zipper tape-attached container 1 by cutting between the top seal portion and the zipper tape 3. In yet another embodiment, the bag body may be provided in a state in which the bottom seal portion 23 is not formed, that is, in a state in which the side of the zipper tape 3 opposite to the storage space S formed inside the zipper tape-attached container 1 is not sealed. In this case, the bottom seal portion 23 is formed after the contents are filled in the storage space S of the zipper tape-attached container 1. In addition to these, the present invention can be applied to known bags and known containers other than bags, as long as the zipper tape 3 is welded.

[0014] [Zipper tape composition] As shown in FIG. 2, the zipper tape 3 is made up of a first member 4 welded to a first surface 21 of a film 20, and a second member 5 welded to a second surface 22 of the film 20. The first member 4 includes a first resin portion 41 and a second resin portion 44. The first resin portion 41 has a first base strip 42 and a male engagement portion 43 that is an engagement portion. The male engagement portion 43 protrudes from the surface of the first base strip 42 that faces the second base strip 52. A tip portion 431 of the male engagement portion 43 will be described in detail later. Meanwhile, the second resin portion 44 covers the surface of the first base strip 42 opposite to the surface on which the male engagement portion 43 is provided. The second resin portion 44 forms a joint portion 4A between the first member 4 and the first surface 21 of the film 20.

[0015] The upper limit of the thickness of the second resin portion 44 is preferably 100 μm or less, more preferably 50 μm or less, and even more preferably 40 μm or less. The lower limit is not particularly limited, but is usually preferably 0.1 μm or more, and more preferably 1 μm or more. As will be described in detail later, the content of the modifier in the second resin portion 44 is lower than the content of the modifier in the first resin portion 41, so that the rigidity of the second resin portion 44 is higher than the rigidity of the first resin portion 41. However, by setting the thickness in this range, it is possible to prevent the rigidity of the zipper tape 3 from becoming too high, thereby reducing folding and disengagement of the zipper tape 3 during manufacturing of the zipper tape 3 or during bag making. The mass ratio of the second resin portion 44 to the first resin portion 41 is preferably 0.1 or more, and more preferably 1% or more. The mass ratio of the second resin portion 44 to the first resin portion 41 is preferably 30% or less, and more preferably 20% or less. Since the content of the modifier in the second resin portion 44 is lower than the content of the modifier in the first resin portion 41, the rigidity of the second resin portion 44 is higher than the rigidity of the first resin portion 41. However, by setting the content within this range, it is possible to prevent the rigidity of the zipper tape 3 from becoming too high, thereby reducing folding and disengagement of the zipper tape 3 during manufacturing of the zipper tape 3 or during bag making.

[0016] The second member 5 includes a first resin portion 51 and a second resin portion 54. The first resin portion 51 has a second base strip 52 and a female engagement portion 53 that constitutes an engagement portion. The second base strip 52 and the first base strip 42 constitute a pair of base strips. The female engagement portion 53 protrudes from the surface of the second base strip 52 that faces the first base strip 42. The female engagement portion 53 can engage with the male engagement portion 43. That is, the female engagement portion 53 has a pair of hook-shaped portions, a first hook portion 531 and a second hook portion 532, that face each other and can receive the male engagement portion 43. On the other hand, the second resin portion 54 covers the surface of the second base strip 52 opposite to the surface on which the female engagement portion 53 is provided. The second resin portion 54 forms a joint portion 5A between the second member 5 and the second surface 22 of the film 20.

[0017] The upper limit of the thickness of the second resin portion 54 is preferably 100 μm or less, more preferably 50 μm or less, and even more preferably 40 μm or less. The lower limit is not particularly limited, but is usually preferably 0.1 μm or more, and more preferably 1 μm or more. As will be described in detail later, the content of the modifier in the second resin portion 54 is lower than the content of the modifier in the first resin portion 51, so that the rigidity of the second resin portion 54 is higher than the rigidity of the first resin portion 41. However, by setting the thickness in this range, it is possible to prevent the rigidity of the zipper tape 3 from becoming too high, thereby reducing folding and disengagement of the zipper tape 3 during manufacturing of the zipper tape 3 or during bag making. The mass ratio of the second resin portion 54 to the first resin portion 51 is preferably 0.1 or more, and more preferably 1% or more. The mass ratio of the second resin portion 54 to the first resin portion 51 is preferably 30% or less, and more preferably 20% or less. Since the content of the modifier in the second resin portion 54 is lower than the content of the modifier in the first resin portion 41, the rigidity of the second resin portion 54 is higher than the rigidity of the first resin portion 51. However, by setting the content within this range, it is possible to prevent the rigidity of the zipper tape 3 from becoming too high, thereby reducing folding and disengagement of the zipper tape 3 during manufacturing of the zipper tape 3 or during bag making.

[0018] In the zipper tape 3 according to the present embodiment, the first resin portions 41, 51 including the pair of base strips, the first base strip 42 and the second base strip 52, and the male engagement portion 43 and the female engagement portion 53, are formed of a first resin composition mainly composed of a first polyester resin. On the other hand, the second resin portions 44, 54 covering the surfaces of the first base strip 42 and the second base strip 52 opposite to the male engagement portion 43 and the female engagement portion 53, respectively, are formed of a second resin composition mainly composed of a second polyester resin. Here, the first polyester resin and the second polyester resin may be, for example, polyethylene terephthalate (PET). The first polyester resin and the second polyester resin may be, for example, a bio-polyester resin that is environmentally friendly. An example of the bio-polyester resin is "RAMAPET N1B" by INDORAMA. The first polyester resin and the second polyester resin may be the same type of polyester resin or different types of polyester resins.

[0019] The first resin composition constituting the first resin portion 41, 51 contains a modifier (first modifier) ​​having an effect of reducing the tensile modulus of elasticity at a first content rate, as described later. In this embodiment, the first content rate is 10% by mass or more. The first content rate is preferably 15% by mass or more, and more preferably 25% by mass or more. In addition, the first content rate is preferably 80% by mass or less, more preferably 70% by mass or less, even more preferably 60% by mass or less, and particularly preferably 50% by mass or less. On the other hand, the second resin composition constituting the second resin portion 44, 54 contains the same type of modifier as the modifier contained in the first resin composition at a second content rate lower than the first content rate, or does not contain a modifier. When the second resin composition contains a modifier, the second content rate is 50% by mass or less. The second content rate is preferably 30% by mass or less, and more preferably 10% by mass or less. When the second resin composition contains the same type of modifier as the modifier (first modifier) ​​contained in the first resin composition, the second content may be any value greater than 0 mass %.

[0020] From the viewpoint of extrudability during production of the zipper tape, the content of the modifier in the first resin composition is preferably 10% by mass to 45% by mass, or 55% by mass to 80% by mass, more preferably 25% by mass to 40% by mass, or 57% by mass to 75% by mass. In this specification, the content of a specific component in a resin composition means the proportion of the specific component in the entire resin composition including the specific component.

[0021] In another example, the second resin composition may contain a modifier (second modifier) ​​different from the modifier contained in the first resin composition in place of the modifier contained in the first resin composition at a third content lower than the first content. In this case, the third content is 50% by mass or less of the second resin composition. The third content is preferably 30% by mass or less, and more preferably 10% by mass or less. The third content may be any value greater than 0% by mass. When the second resin composition contains a modifier (second modifier) ​​different from the first modifier in addition to the modifier (first modifier) ​​contained in the first resin composition, the total content of the modifiers (total of the second content and the third content) is lower than the first content and is 50 mass% or less. The total content of the modifiers is preferably 30 mass% or less, more preferably 10 mass% or less. The total content of the modifiers may be any value greater than 0 mass%. However, it is more preferable that the second resin composition does not contain a modifier than that the second resin composition contains a modifier.

[0022] The above modifiers (first modifier and second modifier) ​​are substances that have the effect of reducing the tensile modulus of the polyester resin. Specifically, the modifier may be, for example, any one of polyester-based elastomers, ionomer resins, acid-modified polyolefins, styrene-based elastomers, polyethylene, polyolefin-based elastomers, and ethylene-vinyl acetate copolymers (EVA), or a mixture of two or more of these. As the ionomer resin, ethylene-methacrylic acid-acrylic acid ester copolymers are preferred. The polyethylene is preferably linear low density polyethylene (LLDPE). That is, as described above, the modifier (first modifier) ​​contained in the first resin composition and the modifier (second modifier) ​​contained in the second resin composition may be the same or different. In addition, the modifier (first modifier) ​​contained in the first resin composition may be a mixture of the modifier (second modifier) ​​contained in the second resin composition and at least one other modifier. Similarly, the modifier (second modifier) ​​contained in the second resin composition may be a mixture of the modifier (first modifier) ​​contained in the first resin composition and at least one other modifier.

[0023] The zipper tape 3 is formed, for example, by co-extrusion of the first resin composition and the second resin composition. In the zipper tape 3 after welding to the film 20, the layer of the first resin portion 41 and the layer of the second resin portion 44 may not be clearly distinguishable, and the layer of the first resin portion 51 and the layer of the second resin portion 54 may not be clearly distinguishable.

[0024] The first resin parts 41, 51 are formed of a first resin composition having a relatively high content of modifier, and the second resin parts 44, 54 are formed of a second resin composition having a relatively low content of modifier or not containing any modifier, so that the tensile modulus of the first resin parts 41, 51 is higher than that of the second resin parts 44, 54. The tensile modulus of the first resin parts 41, 51 is, for example, 100 MPa or more, preferably 200 MPa or more, more preferably 500 MPa or more, even more preferably 710 MPa or more, particularly preferably 770 MPa or more, even more particularly preferably 860 MPa or more, and even more particularly preferably 1000 MPa or more. The tensile modulus of elasticity is 1400 MPa or less, preferably 1300 MPa or less, and more preferably 1200 MPa or less. This allows the male engagement part 43 and the female engagement part 53 that engage with each other to be formed flexibly, and the zipper function can be fully exerted. Furthermore, if the first resin portions 41, 51 have a tensile modulus of elasticity of 100 MPa or more, the engagement strength between the male engaging portion 43 and the female engaging portion 53 is improved, and the engaged state between the male engaging portion 43 and the female engaging portion 53 is better maintained.

[0025] The shapes of the male engaging portion 43 and the female engaging portion 53, which are the engaging portions, are not limited to male and female, and known shapes combining claws, hooks, knobs, etc. may be applied to the engaging portions of the first member 4 and the second member 5. Two or more sets of engaging portions may be provided on the first member 4 and the second member 5. In any case, the engaging portions are irregularly shaped portions protruding from the first base strip 42 and the second base strip 52 having a substantially rectangular cross section. In order to maintain the shape of such irregularly shaped portions and reliably seal the opening 11 when the engaging portions are engaged, and to provide an appropriate feeling of opening when the engagement is released, it is preferable that the elastic modulus of the first resin portions 41, 51 is within the above-mentioned range.

[0026] On the other hand, when a resin composition mainly composed of a polyester resin contains a modifier, the seal strength of a resin layer formed from the resin composition to a layer containing a heat-sealable PET resin is lower than that of a resin layer formed from a resin composition not containing a modifier. In other words, when a modifier is added, there is a trade-off between the elastic modulus and the seal strength. In contrast, in this embodiment, even if the second resin composition contains a modifier, the content of the modifier is lower than the content of the first modifier in the first resin composition (first content) and is less than 30 mass %. This can suppress a decrease in the seal strength of the second resin parts 44, 54. More specifically, the seal strength of the second resin parts 44, 54 to the sealant layers 211, 221 can be, for example, 10 N / 15 mm or more, preferably 15 N / 15 mm or more, and more preferably 20 N / 15 mm or more. In addition, the seal strength of the second resin parts 44, 54 to the sealant layers 211, 221 is, for example, 100 N / 15 mm or less. Therefore, the second resin parts 44, 54 can be firmly welded to the sealant layers 211, 221.

[0027] On the other hand, when the resin composition mainly composed of polyester resin does not contain a modifier, as described above, the seal strength of the resin layer formed of the resin composition with respect to the layer containing heat-sealable PET resin tends to be higher than the seal strength of the resin layer formed of the resin composition containing the modifier. The elastic modulus of the resin layer formed of the resin composition mainly composed of polyester resin and not containing a modifier tends to be higher than the elastic modulus of the resin layer formed of the resin composition containing the modifier. For this reason, by using a resin composition not containing a modifier for the seal layer, a seal layer having high shape stability and high seal strength can be formed. In particular, by adopting a layer formed of a resin composition not containing a modifier for the laminate forming the seal layer, high seal strength and high shape stability can be imparted to the seal layer.

[0028] [Angle of the tip of the male engagement part] FIG. 3 is a cross-sectional view showing the zipper tape-attached container 1 in a state in which the male engaging portion 43 and the female engaging portion 53 are engaged with each other. As shown in FIG. 3, the tip 431 in the protruding direction of the male engagement part 43 from the first base strip 42 is formed in a substantially triangular shape. In this embodiment, the tip angle of the male engagement part 43, i.e., the angle α of the tip 431, is an angle in the range of 60° or more and 130° or less. In detail, the angle α is an intersection angle between a tangent L1 of the part of the tip 431 on the opening 11 side and a tangent L2 of the part of the tip 431 on the storage space S side. According to the knowledge of the inventors, the angle α is preferably 75° or more, more preferably 90° or more. Moreover, the angle α is preferably 120° or less, more preferably 110° or less. This makes it easier to insert the male engagement portion 43 into the concavely formed female engagement portion 53, allowing the zipper to function fully even if the elastic modulus of the first resin composition forming the male engagement portion 43 is relatively low.

[0029] [Thickness dimension of the second member at the female engagement portion] 3, in this embodiment, the minimum thickness LE of the second member 5 at a portion within the female engagement portion 53 is 0.1 mm or more and 1.0 mm or less. More specifically, the minimum thickness LE of the second member 5 is the dimension in the direction from the second member 5 to the first member 4 in the region sandwiched between the first hook portion 531 and the second hook portion 532, which are a pair of hook-shaped portions, in the width direction of the zipper tape 3. According to the findings of the present inventors, the minimum thickness LE is preferably 0.2 mm or more, more preferably 0.3 mm or more. Moreover, the minimum thickness LE is preferably 0.8 mm or less, more preferably 0.6 mm or less. This makes it easier to displace the female engaging portion 53 when inserting the male engaging portion 43. Therefore, it is easier to insert the male engaging portion 43 into the female engaging portion 53, and it is easier to seal the opening 11 of the container 1 with the zipper tape.

[0030] [Effects of the embodiment] The container 1 with zipper tape according to the present embodiment described above provides the following advantages. The zipper tape 3 includes first resin portions 41, 51 formed of a first resin composition mainly composed of a first polyester resin, and second resin portions 44, 54 formed of a second resin composition mainly composed of a second polyester resin. The first resin portion 41 has a first base strip 42 constituting a pair of base strips, and a male engagement portion 43 protruding from a surface of the first base strip 42 facing the second base strip 52. The first resin portion 51 has a second base strip 52 constituting a pair of base strips, and a female engagement portion 53 protruding from a surface of the second base strip 52 facing the first base strip 42. The male engagement portion 43 and the female engagement portion 53 are engagement portions that can be engaged with each other. The second resin portion 44 covers the surface of the first base strip 42 opposite to the male engagement portion 43. The second resin portion 54 covers the surface of the second base strip 52 opposite the female engagement portion 53 . The first resin composition contains a first modifier at a first content rate. The second resin composition contains the first modifier at a second content rate lower than the first content rate, or does not contain the first modifier.

[0031] According to this configuration, the first resin portion 41 having the male engaging portion 43 and the first resin portion 51 having the female engaging portion 53 contain the first modifier at a first content rate. This allows the male engaging portion 43 and the female engaging portion 53 that are engageable with each other to be formed flexibly, and the engageability of the male engaging portion 43 and the female engaging portion 53 can be improved. As described above, as the content of the modifier in the second resin portions 44, 54 increases, the seal strength of the second resin portions 44, 54 to the first surface 21 and the second surface 22, which are the inner surfaces of the container body 2 containing a heat-sealable PET resin, decreases. In contrast, the second resin portions 44, 54 contain the first modifier at a second content rate lower than the first content rate, or do not contain the first modifier. This makes it possible to suppress a decrease in the seal strength of the second resin portions 44, 54 to the first surface 21 and the second surface 22. Therefore, the zipper tape 3 can be configured to be flexible and have high sealing strength.

[0032] In the zipper tape 3, the first polyester resin and the second polyester resin may be the same type of polyester resin. According to this configuration, there is no need to significantly change the polyester resin constituting the zipper tape 3 between the first resin portions 41, 51 and the second resin portions 44, 54. Therefore, the zipper tape 3 can be easily manufactured.

[0033] In the zipper tape 3, when the first polyester resin and the second polyester resin are the same type of polyester resin, the same type of polyester resin may be polyethylene terephthalate (PET). With this configuration, the zipper tape 3 can be formed with excellent strength, chemical resistance and transparency.

[0034] In the zipper tape 3, the first modifier may be made of at least one of polyester elastomer, ionomer resin, acid-modified polyolefin, styrene elastomer, polyethylene, polyolefin elastomer, and ethylene-vinyl acetate copolymer (EVA). The first resin composition contains such a modifier as the first modifier, so that the zipper tape 3 exhibiting the above-mentioned effects can be obtained.

[0035] In the zipper tape 3, the first content may be 10% by mass or more. This configuration can reduce the tensile modulus of the first resin composition containing the first polyester resin and the first modifier, thereby enabling the male engaging portion 43 and the female engaging portion 53, which are the engaging portions, to be flexibly displaceable, thereby improving the engageability of the male engaging portion 43 and the female engaging portion 53.

[0036] In the zipper tape 3, the second resin composition contains the first modifier at a second content, and the second content may be 50 mass % or less. According to such a configuration, it is possible to reduce the content of the first modifier in the second resin portions 44, 54. This makes it possible to suppress a decrease in the seal strength of the second resin portions 44, 54 with respect to the sealant layers 211, 221 on the inner surface of the container body 2, for example. In addition, since the second resin composition contains the same first modifier as the first resin composition, it is possible to facilitate the production of the zipper tape.

[0037] In the zipper tape 3, the second resin composition does not need to contain the first modifier. According to this configuration, the composition of the first resin composition and the composition of the second resin composition can be simplified, the manufacturing cost of the zipper tape 3 can be reduced, and the sealing strength of the second resin portions 44, 54 against the first surface 21 and the second surface 22, which are the inner surfaces of the container body 2, can be increased.

[0038] In the zipper tape 3, the second resin composition may not contain the first modifier, but may contain a second modifier different from the first modifier at a third content lower than the first content. According to such a configuration, the content of the second modifier in the second resin composition can be reduced, so that, for example, a decrease in the seal strength of the second resin portions 44, 54 to the sealant layers 211, 221 of the container body 2 can be suppressed.

[0039] In the zipper tape 3, the third content may be 50% by mass or less. According to this configuration, the second resin composition does not contain the first modifier and contains the second modifier at a third content of 50 mass% or less. This allows the content of the modifier contained in the second resin portions 44, 54 to be low, so that, for example, a decrease in the seal strength of the second resin portions 44, 54 with respect to the sealant layers 211, 221 of the container body 2 can be suppressed.

[0040] In the zipper tape 3, the second resin composition may contain the first modifier at a second content rate and a second modifier different from the first modifier at a third content rate. In this case, the sum of the second content rate and the third content rate may be lower than the first content rate and may be 50 mass % or less. According to such a configuration, even when the second resin composition contains the first and second modifiers, it is possible to reduce the content of the modifiers in the second resin portions 44, 54. Therefore, for example, a decrease in the seal strength of the second resin portion with respect to the sealant layers 211, 221 of the container body 2 can be suppressed.

[0041] In the zipper tape 3, the second modifier may be made of at least one of polyester elastomer, ionomer resin, acid-modified polyolefin, styrene elastomer, polyethylene, polyolefin elastomer, and EVA. The second resin composition contains such a modifier as the second modifier, so that the zipper tape 3 exhibiting the above-mentioned effects can be obtained.

[0042] In the zipper tape 3, the pair of base strips of the first resin part 41, 51 may be composed of a first base strip 42 of the first resin part 41 and a second base strip 52 of the first resin part 51 facing the first base strip 42. In this case, the engagement parts of the first resin parts 41, 51 may include a male engagement part 43 and a female engagement part 53. The male engagement part 43 may be provided on the first base strip 42 and protrude from the first base strip 42 towards the second base strip 52. The female engagement part 53 may be provided on the second base strip 52 and protrude from the second base strip 52 towards the first base strip 42. With this configuration, by inserting the male engaging portion 43 into the female engaging portion 53, the engaged state of the first base strip 42 and the second base strip 52, and ultimately the engaged state of the zipper tape 3, can be maintained.

[0043] In the zipper tape 3, the tip angle of the male engaging portion 43 may be 60° or more and 130° or less. That is, the angle α of the tip 431 in the protruding direction of the male engaging portion 43 from the first base strip 42 may be 60° or more and 130° or less. In this case, the angle α may be preferably 75° or more, more preferably 90° or more. Moreover, the angle α may be preferably 120° or less, more preferably 110° or less. According to such a configuration, it is possible to easily insert the male engaging portion 43 into the female engaging portion 53. In addition, it is possible to make it difficult for the male engaging portion 43 inserted into the female engaging portion 53 to come off from the female engaging portion 53.

[0044] The zipper tape 3 may include a first member 4 and a second member 5. The first member 4 has a first base strip 42, a male engagement portion 43, and a second resin portion 44 covering the surface of the first base strip 42 opposite to the male engagement portion 43. The second member 5 has a second base strip 52, a female engagement portion 53, and a second resin portion 54 covering the surface of the second base strip 52 opposite to the female engagement portion 53. The female engagement portion 53 has a first hook portion 531 and a second hook portion 532 facing each other. The first hook portion 531 and the second hook portion 532 correspond to a pair of hook-shaped portions. In a region sandwiched between the first hook portion 531 and the second hook portion 532 in the width direction of the zipper tape 3, the minimum thickness LE of the second member 5 may be 0.1 mm or more and 1.0 mm or less. The minimum thickness LE may be preferably 0.2 mm or more, more preferably 0.3 mm or more, and may be preferably 0.8 mm or less, more preferably 0.6 mm or less. According to such a configuration, since the female engaging portion 53 can be easily displaced when the male engaging portion 43 is inserted, the male engaging portion 43 can be easily inserted into the female engaging portion 53 .

[0045] The zipper tape 3 may include a first member 4 and a second member 5. The first member 4 has a first base strip 42, a male engagement portion 43, and a second resin portion 44 covering the surface of the first base strip 42 opposite to the male engagement portion 43. The second member 5 has a second base strip 52, a female engagement portion 53, and a second resin portion 54 covering the surface of the second base strip 52 opposite to the female engagement portion 53. The second resin portion 44 may have a thickness of 100 μm or less, and the second resin portion 54 may have a thickness of 100 μm or less. According to such a configuration, the rigidity of the zipper tape 3 can be prevented from becoming too high, thereby reducing folding and disengagement of the zipper tape 3 during production of the zipper tape 3 or during bag making.

[0046] The zipper tape 3 may include a first member 4 and a second member 5. The first member 4 has a first base strip 42, a male engagement portion 43, and a second resin portion 44 covering the surface of the first base strip 42 opposite to the male engagement portion 43. The second member 5 has a second base strip 52, a female engagement portion 53, and a second resin portion 54 covering the surface of the second base strip 52 opposite to the female engagement portion 53. The mass ratio of the second resin portion 44 to the first resin portion 41 may be 0.1% or more and 30% or less. The mass ratio of the second resin portion 54 to the first resin portion 51 may be 0.1% or more and 30% or less. According to such a configuration, the rigidity of the zipper tape 3 can be prevented from becoming too high, thereby reducing folding and disengagement of the zipper tape 3 during production of the zipper tape 3 or during bag making.

[0047] In the zipper tape 3, the first resin portions 41, 51 may have a tensile modulus of 100 MPa or more and 1400 MPa or less. The first resin portions 41, 51 may have a tensile modulus of 200 MPa or more, more preferably 500 MPa or more, further preferably 710 MPa or more, and particularly preferably 860 MPa or more. The first resin portions 41, 51 may have a tensile modulus of 1400 MPa or less, preferably 1300 MPa or less, and more preferably 1200 MPa or less. With this configuration, the male engaging portion 43 and the female engaging portion 53 that engage with each other can be formed flexibly. Therefore, the male engaging portion 43 and the female engaging portion 53 can be easily engaged with each other. For example, as described above, if the tensile modulus of elasticity of the first resin portions 41, 51 is 100 MPa or more, the engagement strength between the male engaging portion 43 and the female engaging portion 53 is improved, and the engaged state between the male engaging portion 43 and the female engaging portion 53 is better maintained.

[0048] The container 1 with zipper tape comprises a zipper tape 3 and a container body 2 to which the zipper tape 3 is welded. According to this configuration, a container 1 with zipper tape that exhibits the same effects as the zipper tape 3 described above can be formed.

[0049] In the container 1 with zipper tape, the container body 2 may have a sealant layer 211, 221 formed of a resin composition mainly composed of heat-sealable polyethylene terephthalate (PET) and to which the second resin parts 44, 54 are welded. In this case, the seal strength of the second resin parts 44, 54 to the sealant layers 211, 221 may be higher than the seal strength of the first resin parts 41, 51 to the sealant layers 211, 221. According to this configuration, by forming a container 1 with zipper tape by welding the zipper tape 3 to the sealant layers 211, 221 of the container body 2, it is possible to achieve both the functionality of the PET layer and the functionality of the zipper tape 3. In addition, since the seal strength of the second resin portions 44, 54 to the sealant layers 211, 221 is higher than the seal strength of the first resin portions 41, 51 to the sealant layers 211, 221, the second resin portions 44, 54 can be stably welded to the sealant layers 211, 221. Therefore, the zipper tape 3 can be stably fixed to the container body 2.

[0050] In the container 1 with zipper tape, the seal strength of the second resin parts 44, 54 to the sealant layers 211, 221 may be 10 N / 15 mm or more. The seal strength of the second resin parts 44, 54 can be 100 N / 15 mm or less. According to this configuration, the second resin portions 44, 54 can be firmly welded to the container body 2. Therefore, the zipper tape 3 can be stably fixed to the container body 2.

[0051] In the container 1 with the zipper tape, the container body 2 may be a bag. With this configuration, an openable and closable bag-shaped container can be formed.

[0052] [Variations] The present invention is not limited to the above-described embodiment, and modifications and improvements within the scope of the present invention that can achieve the object of the present invention are included in the present invention. The first resin composition contains the first modifier at a first content rate, and the first content rate is set to be 10 mass% or more. However, depending on the composition of the first modifier, the first content rate may be any value greater than 0 mass%, and does not necessarily have to be 10 mass% or more.

[0053] When the second resin composition contains the first modifier, the second content of the first modifier is lower than the first content and is 50% by mass or less. When the second resin composition contains the second modifier, the third content of the second modifier is lower than the first content and is 50% by mass or less. When the second resin composition contains the first modifier and the second modifier, the sum of the second content of the first modifier and the third content of the second modifier is lower than the first content and is 50% by mass or less. However, the content of the modifier in the second resin composition does not necessarily have to be 50% by mass or less as long as it is lower than the content of the modifier in the first resin composition. In addition, when the second resin composition contains the first modifier, it is preferable that the second content of the first modifier is lower than the first content and is 40% by mass or less. When the second resin composition contains the second modifier, the third content of the second modifier is lower than the first content and is preferably 40 mass% or less. When the second resin composition contains the first modifier and the second modifier, the sum of the second content of the first modifier and the third content of the second modifier is lower than the first content and is preferably 40 mass% or less.

[0054] The first and second modifiers are exemplified above. However, the composition of the first and second modifiers is not limited to the above, as long as they reduce the tensile modulus of the first resin composition mainly composed of the first polyester resin and the tensile modulus of the second resin composition mainly composed of the second polyester resin.

[0055] The angle α of the tip 431 of the male engagement portion 43 is not limited to the above range and can be changed. In the region sandwiched between the first hook portion 531 and the second hook portion 532 that are a pair of hook-shaped portions, the minimum thickness LE of the second member 5 is not limited to the above-mentioned range and can be changed. The tensile modulus of elasticity of the first resin portions 41, 51 is not limited to the above range and can be changed. The sealing strength of the second resin portions 44, 54 to the sealant layers 211, 221 is not limited to the above range and can be changed.

[0056] [Example] For the container 1 with zipper tape described above, the sealing strength of the second resin composition against the sealant layer formed from a resin composition mainly composed of heat-sealable PET, the elastic modulus of the first resin composition depending on the type of modifier, and the ease of engagement between the male engaging portion 43 and the female engaging portion 53 depending on the values ​​of the angle α and the minimum thickness LE were evaluated.

[0057] [Heat sealability] Using a "thermal gradient tester" manufactured by Toyo Seiki Seisakusho Co., Ltd., a sample film formed of a resin composition containing polyethylene terephthalate (PET) (intrinsic viscosity: 0.88 dl / g, melting point 225°C) as a polyester resin as a main component and containing the modifiers shown below, and a target film formed of a resin composition containing heat-sealable PET as a main component were sealed at a sealing time of 1.0 second, a sealing pressure of 0.2 MPa, and a sealing temperature of 220°C to obtain an evaluation sample. For the evaluation sample, a "digital force gauge" manufactured by Imada Co., Ltd. was used to measure the heat seal strength (N / 15mm) between the sample film and the target film per 15mm width. The pulling speed during the seal strength measurement was 300mm / min.

[0058] In Table 1 shown below, the sample film of Example 1 is a film containing 100 mass % PES (polyethersulfone) resin and containing no modifier. The sample film of Example 2 contains 30% by mass of a PES-based elastomer as a modifier. The sample film of Example 3 contains 50% by mass of a PES-based elastomer as a modifier. The sample film of Example 4 contains 15 mass% of ethylene-methacrylic acid-acrylate copolymer, which is an ionomer resin, as a modifier. The sample film of Example 5 contains 30 mass% of ethylene-methacrylic acid-acrylate copolymer, which is an ionomer resin, as a modifier. The sample film of Example 6 contains 60 mass % of ethylene-methacrylic acid-acrylate copolymer, which is an ionomer resin, as a modifier.

[0059] [Table 1]

[0060] As shown in Table 1, the seal strength was lower in the evaluation sample of Example 1, which was made by sealing a sample film containing 100% by mass of PES resin without any modifier with a target film, the evaluation sample of Example 2, which was made by sealing a sample film made of a resin composition containing PET as the main component and 30% by mass of PES-based elastomer as a modifier with a target film, and the evaluation sample of Example 3, which was made by sealing a sample film made of a resin composition containing PET as the main component and 50% by mass of PES-based elastomer as a modifier with a target film. This tendency is also seen in the evaluation samples, for example, made by sealing a sample film containing an ethylene-methacrylic acid-acrylic acid ester copolymer as a modifier or a sample film containing other modifiers shown in Examples 4 to 6 with a target film. On the other hand, it was found that when the content of modifier contained in the resin composition forming the sample film is 50 mass % or less, the sealing strength of the sample film against a target film formed from a resin composition mainly composed of heat-sealable PET can ensure a sealing strength usable as a zipper tape 3 welded to the sealant layers 211, 221. That is, by setting the content of the modifier in the second resin composition to 50% by mass or less, the zipper tape 3 could be firmly welded to the sealant layers 211, 221.

[0061] Here, the seal strength of the sample film shown in Example 4, i.e., the sample film containing 15 mass% of ethylene-methacrylic acid-acrylic acid ester copolymer as a modifier, was lower than that of the sample film shown in Example 1, i.e., the sample film containing no modifier and 100 mass% PES resin, but was higher than the seal strengths of the other sample films shown in Examples 2, 3, 5 and 6. Therefore, it was confirmed that the seal layer having the composition shown in Example 4 is more useful as a seal layer when formed into a laminate structure. For this reason, for example, a better sealing layer for a film can be constructed by sealing a laminate of a layer containing an ethylene-methacrylic acid-acrylate copolymer and a layer of PET only (a layer not containing an ethylene-methacrylic acid-acrylate copolymer) to a film.

[0062] [Tensile modulus] FIG. 4 is a graph showing the results of measuring the tensile modulus of elasticity of a plurality of test pieces formed from a resin composition containing a modifier. Next, the tensile modulus of the test pieces containing each modifier was measured using an Autograph AGSH-500N (Shimadzu Corporation). The test piece for measuring the tensile modulus was 3.5 mm wide and 150 mm long, cut from a base strip of a zipper tape made of a resin composition having the following composition. The chuck distance of the tensile tester was set to 100 mm, and the test piece was pulled at a pulling speed of 500 mm / min, and the tensile load was measured until the elongation amount reached 0.8 mm. The measured tensile load was divided by the cross-sectional area calculated from the width and thickness of the test piece to obtain the stress (MPa). The elongation amount (mm) was further divided by the chuck distance (mm) to obtain the strain ε, and the stress σ (MPa) was divided by the strain ε to obtain the tensile modulus (MPa). The measurement was performed in an atmosphere with a temperature of 23°C and a relative humidity of 50%.

[0063] The test pieces to be measured were as in Example 1 above, test pieces formed from a resin composition containing 100 mass% PES resin, test pieces formed from a resin composition containing 30 mass% PES-based elastomer as a modifier, test pieces formed from a resin composition containing 15 mass%, 30 mass%, 45 mass%, and 60 mass% saponified EVA resin classified as ethylene-vinyl acetate copolymer (EVA), test pieces formed from a resin composition containing 30 mass% styrene-based elastomer (SEBS type), test pieces formed from a resin composition containing 15 mass%, 30 mass%, 45 mass%, and 60 mass% ethylene-methacrylic acid-acrylate copolymer, which is an ionomer resin, test pieces formed from a resin composition containing 30 mass% and 45 mass% olefin-based elastomer classified as a polyolefin-based elastomer, and test pieces formed from a resin composition containing 30 mass% olefin-based elastomer and 5 mass% compatibilizer. The main component of each resin composition is PET.

[0064] 4, the tensile modulus of elasticity of the test piece formed from a resin composition containing 100% by mass of PES resin was approximately 1600 MPa. Since a resin composition having such a composition is relatively hard, when first resin portions 41, 51 are formed from such a composition, the engagement between male engaging portion 43 and female engaging portion 53 is not good. On the other hand, if the first resin portions 41, 51 are made of a resin composition having a tensile modulus of elasticity of less than 100 MPa, the first resin portions 41, 51 are too soft, and the engagement between the male engaging portion 43 and the female engaging portion 53 is not good. For these reasons, in order to impart appropriate flexibility to the male engagement portion 43 and the female engagement portion 53, it is preferable that the tensile modulus of elasticity of the first resin composition forming the first resin portions 41, 51 is 100 MPa or more and 1400 MPa or less.

[0065] FIG. 5 is a graph showing the measurement results of the tensile modulus of a resin composition containing an ethylene-methacrylic acid-acrylate copolymer as a modifier. On the other hand, in the case of a resin composition containing an ethylene-methacrylic acid-acrylate copolymer as a modifier, the content of the ethylene-methacrylic acid-acrylate copolymer when the tensile modulus is 100 MPa or more and 1400 MPa or less is approximately 15 mass% or more, as shown in Figure 5. In addition, since the tensile modulus of a resin composition containing 30 mass% of a PES-based elastomer is lower than that of a resin composition containing 30 mass% of an ethylene-methacrylic acid-acrylate copolymer, it is estimated that the content of the PES-based elastomer when the tensile modulus of a resin composition containing a PES-based elastomer is 10 mass% or more. The same is true for resin compositions containing an olefin-based elastomer. In this way, depending on the type of modifier added, by making the content of the modifier in the resin composition 10 mass % or more, the tensile modulus of the resin composition can be made 100 MPa or more and 1400 MPa or less.

[0066] In order to improve the engagement between the male engaging portion 43 and the female engaging portion 53, it is also necessary to impart appropriate hardness to the male engaging portion 43 and the female engaging portion 53. For this reason, the tensile modulus of the resin composition forming the first resin portion 41 in which the male engaging portion 43 is formed and the first resin portion 51 in which the female engaging portion 53 is formed is preferably 200 MPa or more, more preferably 500 MPa or more, even more preferably 710 MPa or more, particularly preferably 770 MPa or more, even more particularly preferably 860 MPa or more, and even more particularly preferably 1000 MPa or more. In addition, the tensile modulus of the resin composition forming the first resin portions 41, 51 is preferably 1300 MPa or less, more preferably 1200 MPa or less. For example, when the first resin composition forming the first resin portions 41, 51 contains an ethylene-methacrylic acid-acrylic acid ester copolymer as a modifier, the tensile modulus of the first resin portions 41, 51 can be made 1000 MPa or more and 1200 MPa or less by setting the content of the ethylene-methacrylic acid-acrylic acid ester copolymer to 30 mass % or more and 45 mass % or less, as shown in Figure 5.

[0067] [Angle of the tip of the male engagement part] Next, the ease of engagement between the male engaging portion 43 and the female engaging portion 53 was evaluated according to the angle α of the tip portion 431. The evaluation subjects were Examples 7 and 8 shown below. Example 7 is a zipper tape 3 having first resin portions 41, 51 formed from a resin composition containing PET as a main component and 30 mass% of ethylene-methacrylic acid-acrylic acid ester copolymer as a modifier, and the angle α of the tip 431 of the male engaging portion 43 is 99°. Example 8 is a zipper tape 3 having first resin portions 41, 51 formed from a resin composition containing PET as the main component and 30% by mass of EVA as a modifier, and the angle α of the tip portion 431 of the male engagement portion 43 is 109°.

[0068] In each of the zipper tape 3 of Example 7 and the zipper tape 3 of Example 8, the male engaging portion 43 and the female engaging portion 53 could be easily engaged with each other. That is, it was found that when the angle α was 99° or 109°, the male engaging portion 43 and the female engaging portion 53 could be easily engaged with each other.

[0069] [Minimum thickness of second member in female engagement portion] Next, the ease of engagement between the male engaging portion 43 and the female engaging portion 53 was evaluated according to the value of the minimum thickness LE. The evaluation subjects were Examples 9 and 10 shown below. Example 9 is a zipper tape 3 having first resin portions 41, 51 formed from a resin composition containing PET as a main component and 30 mass % of ethylene-methacrylic acid-acrylic acid ester copolymer as a modifier, and the zipper tape 3 has the above-mentioned minimum thickness LE of 0.307 mm. Example 10 was a zipper tape 3 having first resin portions 41, 51 formed from a resin composition containing PET as the main component and 30% by mass of EVA as a modifier, and having the above-mentioned minimum thickness LE of 0.433 mm.

[0070] In each of the zipper tape 3 of Example 9 and the zipper tape 3 of Example 10, the male engaging portion 43 and the female engaging portion 53 could be easily engaged with each other. That is, it was found that when the minimum thickness LE was 0.307 mm or 0.433 mm, the male engaging portion 43 and the female engaging portion 53 could be easily engaged with each other.

[0071] [Summary of the invention] The present invention will be summarized below. [1] A zipper tape comprises a first resin portion formed of a first resin composition mainly composed of a first polyester resin and including a pair of base strips and engaging portions protruding from opposing surfaces of the pair of base strips and capable of engaging with each other, and a second resin portion formed of a second resin composition mainly composed of a second polyester resin and covering each of the surfaces of the pair of base strips opposite the engaging portions, wherein the first resin composition contains a first modifier in a first content, and the second resin composition contains the first modifier in a second content lower than the first content, or does not contain the first modifier.

[0072] According to this configuration, the first resin portion having the engaging portion contains the first modifier at the first content rate, so that the engaging portions that can engage with each other can be formed flexibly, and the engageability of the engaging portions can be improved. Here, when the second resin portion is welded to the inner surface of a container body containing a heat-sealable PET resin, the higher the content of the modifier in the second resin portion, the lower the seal strength of the second resin portion to the inner surface of the container body. In contrast, since the second resin portion contains the first modifier at a second content rate lower than the first content rate, or does not contain the first modifier, the decrease in the seal strength of the second resin portion to the inner surface of the container body can be suppressed. Therefore, a zipper tape that is flexible and has high sealing strength can be formed.

[0073] [2] In the zipper tape described in [1], the first polyester resin and the second polyester resin may be the same type of polyester resin. According to this configuration, there is no need to significantly change the polyester resin constituting the zipper tape between the first resin portion and the second resin portion, which makes it easier to manufacture the zipper tape.

[0074] [3] In the zipper tape described in [2], the same type of polyester resin may be polyethylene terephthalate (PET). According to this configuration, since the first resin composition and the second resin composition are resin compositions containing polyethylene terephthalate (PET) as a main component, a zipper tape excellent in strength, chemical resistance and transparency can be obtained.

[0075] [4] In the zipper tape according to any one of [1] to [3], the first modifier may be made of at least one of a polyester-based elastomer, an ionomer resin, an acid-modified polyolefin, a styrene-based elastomer, polyethylene, a polyolefin-based elastomer, and an ethylene-vinyl acetate copolymer (EVA). When the first resin composition contains such a modifier as the first modifier, a zipper tape exhibiting the above-mentioned effects can be obtained.

[0076] [5] In the zipper tape according to any one of [1] to [4], the first content may be 10 mass % or more. According to this configuration, the tensile modulus of the first resin composition containing the first polyester resin and the first modifier can be reduced, and therefore the engaging portion can be configured to be flexibly displaceable, thereby improving the engaging property of the engaging portion.

[0077] [6] In the zipper tape described in any one of [1] to [5], the second resin composition may contain the first modifier in the second content, and the second content may be 50 mass% or less. According to this configuration, the content of the first modifier in the second resin portion can be reduced. This can suppress a decrease in the seal strength of the second resin portion against the inner surface of the container body, for example. In addition, since the second resin composition contains the same first modifier as the first resin composition, the zipper tape can be easily manufactured.

[0078] [7] In the zipper tape according to any one of [1] to [5], the second resin composition may not contain the first modifier. According to this configuration, the composition of the second resin composition can be simplified, the manufacturing cost of the zipper tape can be reduced, and the seal strength of the second resin portion against the inner surface of the container body can be increased. In addition, the elastic modulus of the second resin composition can be increased, so that the shape stability of the second resin portion can be improved.

[0079] [8] In the zipper tape described in any one of [1] to [5], the second resin composition may not contain the first modifier, but may contain a second modifier different from the first modifier in a third content lower than the first content. According to such a configuration, the content of the second modifier contained in the second resin composition can be reduced, so that, for example, a decrease in the seal strength of the second resin portion with respect to the container body can be suppressed.

[0080] [9] In the zipper tape according to [8], the third content may be 50 mass % or less. According to this configuration, the second resin portion does not contain the first modifier, and contains the second modifier at a third content of 50 mass% or less. This allows the content of the modifier in the second resin portion to be reduced as described above, and therefore, for example, a decrease in the seal strength of the second resin portion against the inner surface of the container body can be suppressed.

[0081]

[10] In the zipper tape described in any one of [1] to [5], the second resin composition may contain the first modifier in the second content and a second modifier different from the first modifier in a third content, and the sum of the second content and the third content may be lower than the first content and not more than 50 mass%. According to this configuration, even when the second resin composition contains the first and second modifiers, the content of the modifier in the second resin portion can be reduced, and therefore, for example, a decrease in the seal strength of the second resin portion with respect to the container body can be suppressed.

[0082]

[11] In the zipper tape according to any one of [8] to

[10] , the second modifier may be made of at least one of a polyester-based elastomer, an ionomer resin, an acid-modified polyolefin, a styrene-based elastomer, polyethylene, a polyolefin-based elastomer, and an ethylene-vinyl acetate copolymer (EVA). When the second resin composition contains such a modifier as the second modifier, a zipper tape exhibiting the above-mentioned effects can be obtained.

[0083]

[12] In the zipper tape as described in any one of [1] to

[11] , the pair of base strips may comprise a first base strip and a second base strip opposite the first base strip, and the engaging portion may include a male engaging portion provided on the first base strip and protruding from the first base strip toward the second base strip, and a female engaging portion provided on the second base strip and protruding from the second base strip toward the first base strip and engaging with the male engaging portion. According to this configuration, by inserting the male engaging portion into the female engaging portion, the engaged state of the pair of base strips, and therefore the engaged state of the zipper tapes, can be maintained.

[0084]

[13] In the zipper tape described in

[12] , the tip angle of the male engaging portion may be 60° or more and 130° or less. According to this configuration, it is possible to easily insert the male engaging portion into the female engaging portion, and it is also possible to make it difficult for the male engaging portion inserted into the female engaging portion to come off from the female engaging portion.

[0085]

[14] The zipper tape as described in

[12] or

[13] comprises a first member having the first base strip, the male engaging portion, and the second resin portion covering the side of the first base strip opposite the male engaging portion, and a second member having the second base strip, the female engaging portion, and the second resin portion covering the side of the second base strip opposite the female engaging portion, wherein the female engaging portion includes a pair of hook portions facing each other, and a minimum thickness of the second member in a region sandwiched between the pair of hook portions in the width direction of the zipper tape may be 0.1 mm or more and 1.0 mm or less. According to this configuration, the female engaging portion can be easily displaced when the male engaging portion is inserted, so that the male engaging portion can be easily inserted into the female engaging portion.

[0086]

[15] The zipper tape according to any one of

[12] to

[14] , further comprising: a first member having the first base strip, the male engaging portion, and the second resin portion covering the side of the first base strip opposite the male engaging portion; and a second member having the second base strip, the female engaging portion, and the second resin portion covering the side of the second base strip opposite the female engaging portion, wherein a thickness of the second resin portion may be 100 μm or less. According to such a configuration, the rigidity of the zipper tape can be prevented from becoming too high, thereby reducing folding and disengagement of the zipper tape during production of the zipper tape or during bag making.

[0087]

[16] The zipper tape according to any one of

[12] to

[15] , further comprising: a first member having the first base strip, the male engaging portion, and the second resin portion covering a side of the first base strip opposite the male engaging portion; and a second member having the second base strip, the female engaging portion, and the second resin portion covering a side of the second base strip opposite the female engaging portion, wherein a mass ratio of the second resin portion to the first resin portion may be 0.1% or more and 30% or less. According to such a configuration, the rigidity of the zipper tape can be prevented from becoming too high, thereby reducing folding and disengagement of the zipper tape during production of the zipper tape or during bag making.

[0088]

[17] In the zipper tape according to any one of [1] to

[16] , the first resin portion may have a tensile modulus of elasticity of 100 MPa or more and 1400 MPa or less. According to this configuration, the male engaging portion and the female engaging portion that engage with each other can be formed flexibly, and therefore the male engaging portion and the female engaging portion can be easily engaged with each other.

[0089]

[18] A container with a zipper tape, comprising: the zipper tape described in any one of [1] to

[17] ; and a container body to which the zipper tape is welded. According to this configuration, a container with zipper tape can be formed that has the same effects as the above-mentioned zipper tape.

[0090]

[19] In the container with zipper tape described in

[18] , the container body is formed of a resin composition mainly composed of heat-sealable polyethylene terephthalate (PET) and has a sealant layer to which the second resin portion is welded, and the sealing strength of the second resin portion relative to the sealant layer may be higher than the sealing strength of the first resin portion relative to the sealant layer. According to this configuration, a container with zipper tape is formed by welding a zipper tape to a sealant layer formed in the container body from a resin composition whose main component is heat-sealable PET, thereby making it possible to achieve both the functionality of the PET layer and the functionality of the zipper tape. In addition, since the sealing strength of the second resin portion to the sealant layer is greater than the sealing strength of the first resin portion to the sealant layer, the second resin portion can be stably welded to the sealant layer, and therefore the zipper tape can be stably fixed to the container body.

[0091]

[20] In the container with zipper tape described in

[19] , the second resin portion may have a seal strength with respect to the sealant layer of 10 N / 15 mm or more. According to this configuration, the second resin portion can be firmly welded to the container body, and therefore the zipper tape can be stably fixed to the container body.

[0092]

[21] In the container with zipper tape described in any one of

[18] to

[20] , the container body may be a bag body. With this configuration, an openable and closable bag-shaped container can be formed. [Explanation of symbols]

[0093] 1...container with zipper tape, 2...container body, 3...zipper tape, 4...first member, 41...first resin portion, 42...first base strip, 43...male engagement portion, 44...second resin portion, 5...second member, 51...first resin portion, 52...second base strip, 53...female engagement portion, 531...first hook portion (hook-shaped portion), 532...second hook portion (hook-shaped portion), 54...second resin portion.

Claims

1. a first resin portion formed of a first resin composition containing a first polyester resin as a main component, the first resin portion including a pair of base strips and engaging portions protruding from opposing surfaces of the pair of base strips and capable of engaging with each other; a second resin portion formed of a second resin composition containing a second polyester resin as a main component and covering each of the surfaces of the pair of base strips opposite to the engaging portion; Equipped with The first resin composition contains a first modifier at a first content ratio, the second resin composition contains the first modifier in a second content lower than the first content, or does not contain the first modifier.

2. The zipper tape according to claim 1 , wherein the first polyester resin and the second polyester resin are the same type of polyester resin.

3. 3. The zipper tape of claim 2, wherein the same type of polyester resin is polyethylene terephthalate (PET).

4. 4. The zipper tape according to claim 1, wherein the first modifier is at least one of a polyester-based elastomer, an ionomer resin, an acid-modified polyolefin, a styrene-based elastomer, polyethylene, a polyolefin-based elastomer, and an ethylene-vinyl acetate copolymer (EVA).

5. The zipper tape according to claim 1 , wherein the first content is equal to or greater than 10% by mass.

6. The second resin composition contains the first modifier at the second content, The zipper tape according to claim 1 , wherein the second content is 50% by mass or less.

7. The zipper tape according to claim 1 , wherein the second resin composition does not contain the first modifier.

8. 6. The zipper tape according to claim 1, wherein the second resin composition does not contain the first modifier, and contains a second modifier different from the first modifier in a third content lower than the first content.

9. The zipper tape according to claim 8 , wherein the third content is 50% by mass or less.

10. The second resin composition contains the first modifier at the second content ratio and a second modifier different from the first modifier at a third content ratio; The zipper tape according to claim 1 , wherein a sum of the second content and the third content is lower than the first content and is 50 mass % or less.

11. 11. The zipper tape according to claim 8, wherein the second modifier is at least one of a polyester-based elastomer, an ionomer resin, an acid-modified polyolefin, a styrene-based elastomer, polyethylene, a polyolefin-based elastomer, and an ethylene-vinyl acetate copolymer (EVA).

12. The pair of base strips include: a first base strip; and a second base strip opposite the first base strip; The engagement portion is a male engagement portion provided on the first base strip and projecting from the first base strip toward the second base strip; 12. The zipper tape according to claim 1, further comprising: a female engaging portion provided on the second base strip, protruding from the second base strip toward the first base strip and engaging with the male engaging portion.

13. The zipper tape according to claim 12, wherein a tip angle of the male engaging portion is not less than 60° and not more than 130°.

14. a first member including the first base strip, the male engagement portion, and the second resin portion covering a surface of the first base strip opposite the male engagement portion; a second member having the second base strip, the female engagement portion, and the second resin portion covering a surface of the second base strip opposite the female engagement portion, The female engagement portion includes a pair of hook-shaped portions facing each other, 14. The zipper tape according to claim 12 or 13, wherein a minimum thickness of the second member in a region sandwiched between the pair of hook-shaped portions in the width direction of the zipper tape is 0.1 mm or more and 1.0 mm or less.

15. a first member including the first base strip, the male engagement portion, and the second resin portion covering a surface of the first base strip opposite the male engagement portion; a second member having the second base strip, the female engagement portion, and the second resin portion covering a surface of the second base strip opposite the female engagement portion, The zipper tape according to claim 12 , wherein the second resin portion has a thickness of 100 μm or less.

16. a first member including the first base strip, the male engagement portion, and the second resin portion covering a surface of the first base strip opposite the male engagement portion; a second member having the second base strip, the female engagement portion, and the second resin portion covering a surface of the second base strip opposite the female engagement portion, 16. The zipper tape according to claim 12, wherein a mass ratio of the second resin portion to the first resin portion is 0.1% or more and 30% or less.

17. The zipper tape according to claim 1 , wherein the first resin portion has a tensile modulus of elasticity of 100 MPa or more and 1400 MPa or less.

18. The zipper tape according to any one of claims 1 to 17, A container with a zipper tape comprising: a container body to which the zipper tape is welded.

19. the container body is formed of a resin composition mainly composed of heat-sealable polyethylene terephthalate (PET), and has a sealant layer to which the second resin portion is welded; 20. The container with zipper tape according to claim 18, wherein a seal strength of the second resin portion to the sealant layer is higher than a seal strength of the first resin portion to the sealant layer.

20. 20. The container with zipper tape according to claim 19, wherein a seal strength of the second resin portion to the sealant layer is 10 N / 15 mm or more.

21. The container with a zipper tape according to any one of claims 18 to 20, wherein the container body is a bag.

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