JPH0937815A - Engaging element and packaging bag with engaging element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide engaging elements which are well fusible to polyester sealant layers of a bag body and have excellent reopening and crushing properties and a packaging bag with these engaging elements. SOLUTION: The male member 12 of the engaging elements 11 consists of a band-shaped base part 15, a head part 16 and a connecting part 17 for connecting the both parts 15, 16. The band-shaped base part 15 and the connecting part 17 are joined via an adhesive resin layer 31. A female member 13 consists of a band-shaped base part 18 and a first and a second hook parts 19, 21. The band-shaped base part 18 and these hook parts 19, 21 are joined via an adhesive resin layer 32. The band-shaped base parts 15, 18 consist of PBT(polybutyrene terephthalate) or a copolymer or mixture composed of the PBT and polyether. The parts 16, 17, 19, 21 exclusive of the band-shaped base parts consist of polyethylene having a modulus of elasticity in bending of 50 to 500MPa.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engaging device and a packaging bag with an engaging device, which is used for packaging foods and medical products.

[0002]

BACKGROUND ART [PROBLEMS TO BE SOLVED BY THE INVENTION] A band-shaped engaging device (fitting device) including a male member and a female member at an opening portion of a bag.
A zipper bag that can be opened and closed by installing
Is used in many fields such as food, pharmaceuticals and sundries. Then, various methods have been proposed as a method of manufacturing the bag with an engaging device.

For example, a method of integrally extruding and molding a tubular film having a male member and a female member of an articulation tool using an extrusion die, a tape with the articulation tool is manufactured in advance, and this tape is used as a bag. There is a method of heat fusion bonding to a base material film forming a main body. The former method has the drawbacks that if it is made as an integral body from the beginning, it will take up space due to the shape of the articulation tool, which makes it inconvenient to store and handle, and has restrictions on the structure of the base film. So, in recent years,
The latter method, which does not have these drawbacks, is becoming common.

Low density polyethylene (LDPE) and polypropylene (PP) are generally used as the material of the engaging device, and the sealant layer, which is a film layer to which the engaging device of the bag body is fused, is of the same type as the engaging device. It is said to be a resin. For example, when the sealant layer of the base film is made of LDPE, the same LDPE is used as the material of the engaging device. As described above, in the case of the conventional articulator, if the sealant layer is made of the same kind of resin as the articulator, the articulator can be fused to the sealant layer without any trouble.

On the other hand, polyester resins are preferably used as a sealant layer of the bag body because they are excellent in heat resistance, aroma retaining property and gas barrier property. However, when the sealant layer is made of polyester resin, which is a material different from that of the clasp, it is difficult to fuse the clasp to the bag body, and it is difficult to use the polyester resin as the sealant layer. It was

In order to solve such a problem, conventionally,
When the sealant layer of the bag body is made of a polyester resin, an articulation tool containing polybutylene terephthalate (PBT) as a main component has been proposed (Japanese Patent Laid-Open No. 6-91540). However, although the articulation tool containing PBT as a main component can be well fused to the polyester sealant layer of the bag body, it has a problem that it has high rigidity and is difficult to be repeatedly opened and resealed. Further, since the temperature at the time of collapsing the engaging device at the end of the bag is high and the film of the bag body is easily deteriorated by heat, the appearance of the packaging bag may be deteriorated.

Therefore, an object of the present invention is to provide an occluding tool and a packaging bag with an occluding tool which can be well fused to the polyester-based sealant layer of the bag body and which is also excellent in resealability and crushability. .

[0008]

In the articulation tool according to the first aspect of the present invention, the male member and the female member each have a fusion-bonded portion to the bag body, and a portion other than this fusion-bonded portion. The fused portion is made of polybutylene terephthalate (PBT), and the portion other than the fused portion is made of a synthetic resin having a flexural modulus of 50 to 500 MPa. When the bending elastic modulus of the portion other than the fusion-bonded portion is less than the above range, the occlusal strength is weakened, and feeding out during bag making becomes difficult. On the other hand, if it exceeds the above range, the strength after repeated opening and resealing may be reduced, or the occlusion device may be damaged. Examples of the synthetic resin include polyethylene and polypropylene.

An engaging device according to a second aspect of the present invention is characterized in that, in the first aspect, the fusion bonding portion is made of a copolymer or mixture of PBT and polyether. Among the above polyethers, aromatic polyethers are preferable, and the copolymer of this aromatic polyether and PBT is one kind of thermoplastic elastomer.

When the fused portion is a copolymer of PBT and polyether, PBT becomes a hard segment showing strength and heat resistance, and polyether becomes a soft segment showing flexibility. As a specific example of the aromatic polyether, the compound of Chemical formula 1 can be mentioned. A specific example of the copolymer is a block copolymer of PBT and the aromatic polyether of Chemical formula 1. This copolymer has excellent high temperature properties, and exhibits high strength and good rubber elasticity in a wide temperature range from low temperature to high temperature.

[0011]

Embedded image

[0012] The content of PBT in the copolymer is related to the adhesive strength between the fused portion and the portion other than the fused portion (or the adhesive strength with the bag body). There is no practical problem as long as the content is such that the adhesive strength with the portion other than the fused portion is greater than the occlusal strength between the male member and the female member.

The third aspect of the present invention is the engaging device according to the first or second aspect, wherein the fusion-bonded portion to the bag body and the portion other than the fusion-bonded portion are joined together via an adhesive resin layer. It is characterized by being. The adhesive resin includes, for example, a polyolefin-based adhesive resin. The polyolefin-based adhesive resin is a resin having a structure in which an unsaturated carboxylic acid is partially graft-bonded to a mixture of one kind or two or more kinds of polyolefin.

Specific examples of the polyolefin include low density polyethylene, linear low density polyethylene, ethylene / vinyl acetate copolymer, ethylene / butene-1 copolymer, ethylene / propylene copolymer and polybutadiene.
Maleic anhydride is preferably used as the unsaturated carboxylic acid. Since the adhesive resin of the adhesive resin layer has good compatibility with the fused portion and the portion other than the fused portion, it is bonded to the fused portion and the portion other than the fused portion via this adhesive resin layer. Strength increases.

An articulating tool according to a fourth aspect of the present invention is the first to the first aspect.
In any one of the third invention, the synthetic resin is polyethylene (PE). Since the melting point of PE is about 120 ° C, by selecting a resin having a larger melting point difference than this PE as the base resin of the bag body, when crushing the clasp during bag making, You can easily crush it. For example, if the bag body is composed of stretched polyethylene terephthalate (mp.265 ° C) layer / PBT and aromatic polyether copolymer (mp.200 ° C) layer, and the copolymer layer is a sealant layer, 120 ° C The PE part of the articulating device can be crushed without affecting the bag body at a temperature slightly higher than that.

Among the PEs mentioned above, low density polyethylene (LD
PE), especially linear low density polyethylene (L-LDPE) is preferably used. Also, polyethylene has an MI of 1 to 15
It is preferably g / 10 min, more preferably 2 to 8 g / 10 min. If MI is less than 1 g / 10 minutes, melt fracture tends to occur, and if it is more than 15 g / 10 minutes, moldability (mold holding property) is deteriorated.

The parts other than the fusion-bonded part are made of materials other than PE.
Although it is possible to use PP, EVA, EMAA, etc., LDPE is generally used as a material for the articulation device. In the occlusion device according to the present invention, the band-shaped base has a two-layer structure including a first layer that serves as the fusion-bonded portion to the bag body and a second layer laminated on the first layer, and only the first layer is formed. Although it may be PBT or a copolymer of PBT and polyether, in order to prevent fusion between the male member side strip base and the female member side strip base during bag making,
It is preferable to use the entire band-shaped base.

In the packaging bag with an engaging device according to the fifth aspect of the present invention, the engaging device according to any one of the first to fourth aspects is fused to the bag body via the fusion-bonding portion. Characterize.

A packaging bag with an engaging device according to a sixth aspect of the present invention is characterized in that, in the fifth aspect, the film layer fused with the fusion-bonding portion of the engaging device of the bag body is made of polyester resin. And The polyester resin includes polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyester elastomer, polycarbonate and the like. Also, a blend of a polyester resin and a polyolefin resin may be used.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] As shown in FIGS. 1 and 2, an articulation tool 11 according to the present embodiment includes a belt-shaped male member 12 on one side and a female member 12 on the one side.
And the other female member 13 that engages with.
The male member 12 is composed of a belt-shaped base portion 15 fused to the bag body 14, a head portion 16 having a heart-shaped cross section, and a coupling portion 17 having a rod-shaped cross-section for coupling the both portions 15, 16. The strip-shaped base portion 15 and the connecting portion 17 are joined together via an adhesive resin layer 31.

The female member 13 is arranged so as to face the band-shaped base portion 18 fused to the bag body 14, the arcuate first hook portion 19 formed on the base portion 18 and the first hook portion 19. It comprises an arcuate second hook portion 21 formed on the strip-shaped base portion 18. The belt-shaped base portion 18 and the first and second hook portions 1 thereof
It is joined to 9,21 via an adhesive resin layer 32. The strip-shaped base portions 15, 18 are PBT or PBT.
And a polyether, or a mixture of PBT and a polyether.

Further, the head portion 16, the connecting portion 17 and the hook portions 19 and 2
1 is a synthetic resin having a flexural modulus of 50 to 500 MPa, specifically polyethylene. The male member 12 has a strip base 15
The adhesive resin layer 31 and the other portions 16 and 17 can be manufactured by fusion-bonding by coextrusion. Similarly, the female member 13 can also be manufactured by fusion-bonding the strip-shaped base portion 18, the adhesive resin layer 32, and the other portions 19 and 21 by coextrusion.

In the bag 24 with the engaging device 11, the engaging device is
11, the strip-shaped base portions 15 and 18 of the respective members 12 and 13 are fused and attached to the film 25 that constitutes the bag body 14. The film 25 is made of polyester resin.

[Second Embodiment] As shown in FIGS. 3 and 4, an articulation tool 11 according to the present embodiment includes a male member 12 in the form of a belt.
And the other female member 13 that engages with the female member 12. The male member 12 is composed of a belt-shaped base portion 15 fused to the bag body 14, a head portion 16 having a heart-shaped cross section, and a coupling portion 17 having a rod-shaped cross-section for coupling the both portions 15, 16. The female member 13
Is formed on the belt-shaped base portion 18 so as to face the belt-shaped base portion 18 fused to the bag body 14, the arc-shaped first hook portion 19 formed on the base portion 18, and the first hook portion 19. The second hook portion 21 has an arc shape.

Band-shaped bases 15, 18 of the male member 12 and the female member 13
Is a first layer 22 which is a fusion-bonded portion to the bag body 14, and the first layer 22.
It has a two-layer structure with a second layer 23 laminated on 22. The first layer 22 and the second layer 23 are joined via an adhesive resin layer 33. The first layer 22 is formed of PBT, a copolymer of PBT and polyether, or PB.
It consists of a mixture of T and polyether. Also, the second layer 2
3, the connecting portion 17, the head portion 16 and the hook portions 19 and 21 are made of a synthetic resin having a bending elastic modulus of 50 to 500 MPa, specifically, polyethylene.

The male member 12 can be manufactured by fusion-bonding the first layer 22 and the other portions 23, 16, 17 by coextrusion. Similarly, the female member 13 also has the first layer 22.
And other portions 23, 19, and 21 can be manufactured by fusing by coextrusion. In the bag 24 with the engaging device 11, the first device 22 of the belt-shaped bases 15 and 18 of the members 12 and 13 is fused and attached to the film 25 constituting the bag body 14 of the engaging device 11. The film 25 is made of polyester resin.

[0027]

【Example】

Example 1 In the first embodiment, the strip base 1
The material of 5,18 was PBT. The product name of PBT used is BZ-11 (manufactured by Toray Industries, Inc.). In addition, the material of the parts 16, 17, 19, 21 other than the strip-shaped bases 15, 18 has a bending elastic modulus: 200
MPa, MI: 6g / 10min Linear low density polyethylene (L-LD
PE). The product name of this L-LDPE is Idemitsu Moretec (made by Idemitsu Petrochemical Co., Ltd.).

The material of the adhesive resin layers 31 and 32 is a polyolefin adhesive resin. The product name of the polyolefin adhesive resin used is Admer SE800 (manufactured by Mitsui Petrochemical Co., Ltd.). This MI is 4.4g / 10 minutes (190 ℃)
It is. The film 25 constituting the bag body 14 is a two-layer structure film of a stretched polyethylene terephthalate (PET) layer / polybutylene terephthalate (PBT) and a copolymer layer of an aromatic polyether, and a film of PBT and an aromatic polyether. The polymer layer was used as a sealant layer. This aromatic polyether has the structural formula shown in Chemical Formula 1 above. The trade name of the copolymer used is Hytrel 6347 (manufactured by Toray DuPont Co., Ltd.).

Example 2 In the first embodiment, the material of the strip-shaped base portions 15 and 18 is a block copolymer of PBT and aromatic polyether. The copolymer used is
It is Hytrel 6347 (trade name). The materials of the portions 16, 17, 19, 21 other than the strip-shaped base portions 15, 18 and the materials of the adhesive resin layers 31, 32 are the same as those in the first embodiment. The film 25 that constitutes the bag body 14 is also the same as in the first embodiment.

Example 3 In the first embodiment, the material of the strip bases 15 and 18 is a mixture of PBT and aromatic polyether (PBT 60 wt%). This aromatic polyether is represented by the above chemical formula 1. Strip base 15,1
The material of the portions 16, 17, 19, 21 other than 8 and the material of the adhesive resin layers 31, 32 are the same as those in the first embodiment. The film 25 that constitutes the bag body 14 is also the same as in the first embodiment.

Example 4 In the second embodiment, the first layer 22 of the strip-shaped base portions 15 and 18 was Hytrel 6347 (trade name), which is the same copolymer as in Example 2. Also, the male member 12
And portions of the female member 13 other than the first layer 22, 23, 16, 17, 19,
21 was the same L-LDPE as in Example 1. The adhesive resin layer 33
The material of is the same as the adhesive resin layers 31 and 32 of the first embodiment. The film 25 forming the bag body 14 is also the same as in the first embodiment.

Comparative Example 1 The shapes of the male member and the female member of the engaging device are the same as those of the engaging device of the above embodiment, but the male member and the female member are all made of the same material. That is, the male member and the female member of this comparative example are all made of Hytrel 6347 (trade name), which is the same copolymer as in Example 2.

Next, the occluding tools of Examples 1 to 4 and Comparative Example 1
For 11, various characteristics were investigated. That is, the investigated characteristics are the fusion property to the bag body, the occlusal strength after repeated reopening and closing, and the crushing property of the occluding tool at the end of the bag. Table 1 shows the measurement results of the characteristics. The method for testing the characteristics is as follows.

Regarding the fusing property to the bag body, it is necessary to obtain a practically required fusing strength of 1 kg / 15 mm when fusing the engaging device of the above example to the bag body of the above example. Various temperatures were measured.

Regarding the occlusal strength after repeated reopening and closing,
The 50 mm wide articulator was repeatedly opened and closed 10 times and then pulled at a constant speed (300 mm / min) to measure the maximum load when the articulator was opened. A tensile tester (Shimadzu DCS-500 type) was used for this measurement. Regarding the crushability of the bite at the end of the bag, the temperature required to sufficiently crush the bite was measured.

[0036]

[Table 1]

From Table 1, according to the engaging device 11 and the packaging bag 24 with the engaging device according to Examples 1 to 4, the male member 12 and the female member 13 are provided.
Is a strip-shaped base portion 15 or 18 which is a fusion-bonded portion to the bag body 14, respectively.
Or the first layer 22 of the strip-shaped base portion 15,18 and the portion 16,17,19,21,23 other than this fusion portion, the strip-shaped base portion 15,18 or the first layer 22 is PBT, or PBT It can be seen that the fusion temperature is low and the fusion property of the bag body 14 to the polyester-based sealant layer is good because it is made of a copolymer of polyether or a mixture of PBT and polyether.

Further, in this embodiment, since the flexural modulus of the portions 16, 17, 19, 21, 23 other than the fusion-bonded portion is low density polyethylene of 50 to 500 MPa, after re-opening and closing several times, However, deterioration of the occlusal strength was not seen, indicating that the stability of the occlusal strength is good. Furthermore, the crushing temperature of the articulation tool 11 is low,
As a result, the film 25 of the bag body 14 hardly undergoes thermal deterioration, so that the outer appearance of the packaging bag 24 is finished neatly.

On the other hand, from Table 1, according to Comparative Example 1, since the male member and the female member were all made of the same block copolymer of PBT and polyether as in Example 2, the polyester-based sealant layer of the bag main body was used. As for the fusion property to the same as that of the example. However, since the part other than the fusion-bonded part to the bag body is the same copolymer, it can be seen that the occlusal strength deteriorates and the occlusal strength is poorly stable after reopening and closing several times. . Furthermore, since the crushing temperature of the engaging device is high and the film of the bag body is easily thermally deteriorated, the appearance of the packaging bag may be deteriorated.

[0040]

According to the present invention, there can be obtained an occluding tool and a packaging bag with an occluding tool which can be well fused to the polyester sealant layer of the bag body and which is also excellent in resealability and crushability.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an engaging device and a packaging bag with an engaging device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of an occlusion device and a packaging bag with an occlusion device according to the first embodiment.

FIG. 3 is a cross-sectional view of an occlusion device and a packaging bag with an occlusion device according to a second embodiment of the present invention.

FIG. 4 is a cross-sectional view of an engaging device and a packaging bag with an engaging device according to a second embodiment.

[Explanation of symbols]

 11 Coupling device 12 Male member 13 Female member 14 Bag body 15,18 Band base 19 First hook portion 21 Second hook portion 22 First layer 23 Second layer 24 Packaging bag 25 Film constituting the bag body 31,32 , 33 Adhesive resin layer

Claims (6)

[Claims] 1. A male member and a female member each have a fusion-bonded portion to a bag body and a portion other than this fusion-bonded portion, wherein the fusion-bonded portion is made of polybutylene terephthalate (PBT), A part other than the part is made of synthetic resin having a bending elastic modulus of 50 to 500 MPa, which is an articulating tool. 2. The fused portion is made of a copolymer or mixture of PBT and polyether.
The occlusion device described in. 3. The occlusion device according to claim 1, wherein the fusion-bonded portion to the bag body and a portion other than the fusion-bonded portion are joined together via an adhesive resin layer. . 4. The obturator according to claim 1, wherein the synthetic resin is polyethylene. 5. A packaging bag with an engaging device, wherein the engaging device according to any one of claims 1 to 4 is fused to the bag body via the fusion bonding part. 6. The packaging bag with an engaging device according to claim 5, wherein the film layer fused with the fusion bonding portion of the engaging device of the bag body is made of polyester resin.