JP2010143624A - Laminated film for spout container and spout container using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated film for a spout container which achieves a high sealability for the welded areas of a spout container that has a spout formed such that the periphery of the portion jointed to the film is 70 mm or more, and to provide a spout container using the same. <P>SOLUTION: The laminated film 5 for the spout container includes: a base material layer 1 with 400 to 800% tensile elongation; a sealant layer 2 with 500 to 1,000% tensile elongation; and a joint layer 3 formed between the base material layer 1 and sealant layer 2 by extrusion lamination, and serving to join the base material layer 1 and sealant layer 2. The spout container 10 includes: a container body 7 formed by processing the laminated film 5 for the spout container into a bag shape, with the sealant layer 2 inside; and a spout 8 having a channel, by which the inside and outside of the container body 7 communicate with, and attached to a peripheral part of the container body 7. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a spout container in which a spout having a large diameter is welded and attached to a container main body portion in which a synthetic resin sheet is formed in a bag shape. Spout containers are used for filling liquids and powders.

  A spout container (a pouch container with a spout) is known in which a container body made of a synthetic resin sheet is filled with liquid, powder or the like, and a spout serving as a spout is attached to the opening of the container body. The spout container is manufactured by heat-welding a spout integrally molded with a synthetic resin or the like in a state of being sandwiched between synthetic resin sheets and fixing the spout container to the container body. In order to ensure high sealing performance of the spout container, high sealing performance is required at the welding location between the spout and the container main body.

Various spouts having various configurations have been developed so far, from the viewpoint of ensuring high sealing performance at the weld location. For example, in Patent Document 1 below, in a welding and fixing process with a synthetic resin sheet, a predetermined mechanical strength is maintained and partial deformation is prevented, thereby maintaining a good product yield with excellent sealing properties and adhesiveness. A spout for is described.
JP 2006-232295 A

  However, conventionally, when a spout having a large diameter (for example, the outer periphery of the joint portion with the film is 70 mm or more) and made of a highly rigid material is thermally welded to the container main body portion, The sealing performance was not always sufficient. In this case, the content leaks from the said location, or the malfunction that the inside of a spout container cannot fully be maintained in a vacuum state arises.

  This invention is made | formed in view of the said situation, and it aims at providing the spout container using the laminated film for spout containers which can achieve the high sealing performance of the welding location of a spout container, and this.

  The present inventors pay attention to the fact that the conventional synthetic resin sheet does not form neatly into a spout shape when the spout used has a relatively large aperture and is made of a highly rigid material. We studied earnestly about the solution. As a result, the present inventors have found that a laminated film obtained by laminating a base material layer and a sealant layer having a predetermined tensile elongation by extrusion lamination is extremely useful for producing a spout container having high sealing performance. It came to complete.

  That is, the present invention includes a base material layer having a tensile elongation of 400 to 800%, a sealant layer having a tensile elongation of 500 to 1000%, and a base material layer formed by extrusion lamination between the base material layer and the sealant layer. Provided is a laminated film for a spout container comprising a bonding layer for bonding a sealant layer and a sealant layer.

  Since the laminated film according to the present invention has a high tensile elongation, it can be disposed so as to be sufficiently along the outer peripheral surface of the spout in the spout welding operation. By performing welding in this state, it is possible to achieve high sealing performance at the welding location. Moreover, since the laminated film which concerns on this invention has high tensile elongation, even if the outer periphery of the junction part with the film of the spout to be used is 70 mm or more, the high sealing performance of a welding location can be achieved. In addition, according to the laminated film having a high tensile elongation, stress generated in the laminated film after welding can be reduced and high sealing performance can be maintained over a long period of time compared to the case where a conventional synthetic resin sheet is used. . The “tensile elongation” as used in the present invention means a value measured in accordance with a tensile property test method defined in JIS K7127.

  The base material layer is composed of a plurality of layers formed by coextrusion, and at least one of the front surface and the back surface is preferably formed of a polyolefin resin. By adopting such a configuration, the base material layer can be sufficiently prevented from being damaged or torn. The base material layer may have at least two polyolefin resin layers and a resin layer provided between the polyolefin resin layers and having gas barrier properties. By adopting such a configuration, it is possible to sufficiently suppress the alteration of the contents.

  From the viewpoints of weldability with spout and shapeability, it is preferable that the tensile elongation of the sealant layer is larger than the tensile elongation of the base material layer. Further, from the same viewpoint, the sealant layer preferably contains an olefin resin or / and a thermoplastic elastomer.

  It is preferable that the said joining layer contains a polyethylene resin or a polypropylene resin from an adhesive viewpoint with a base material layer and a sealant layer. The thickness of the bonding layer is preferably 5 to 30 μm. By setting the thickness of the bonding layer within the above range, the base material layer and the sealant layer can be bonded with sufficiently high strength, and a laminated film having a high tensile elongation can be obtained.

  The present invention has a container main body formed by processing the laminated film for a spout container into a bag shape with a sealant layer on the inside, and a flow path that communicates the inside and the outside of the container main body. A spout container provided with a spout attached to a peripheral portion of the spout. According to the spout container according to the present invention, since the container main body portion is made of the above-mentioned laminated film for a spout container, high sealing performance even when a spout having an outer periphery of a joint portion with the film of 70 mm or more is used. Can be achieved.

  According to the present invention, even when a spout made of a material having a relatively large diameter and a high rigidity is used, a high sealing performance at a welding location of the spout container can be achieved.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing a laminated film for a spout container according to this embodiment. FIG. 2 is a perspective view showing the spout container according to the present embodiment.

<Laminated film for spout containers>
The spout container laminated film 5 according to the present embodiment is formed by bonding the base material layer 1 that forms the outer layer, the sealant layer 2 that forms the inner layer, and the base material layer 1 and the sealant layer 2 when processed into a bag shape. Layer 3. As shown in FIG. 1, the laminated film 5 has a multilayer structure in which the base material layer 1, the bonding layer 3, and the sealant layer 2 are laminated in this order from the outside. The laminated film 5 is for forming the container body 7 of the spout container 10 shown in FIG.

  A film having a tensile elongation of 400 to 800% is used as the base material layer 1. When the tensile elongation of the base material layer 1 is less than 400%, the tensile elongation of the laminated film 5 becomes insufficient. The lower limit of the tensile elongation of the base material layer 1 is preferably 450%, and more preferably 500%. On the other hand, when a film having a tensile elongation exceeding 800% is used, it is difficult to maintain the strength of the container. Considering the balance between the strength of the container and the bondability with the spout, the upper limit of the tensile elongation of the base material layer 1 is preferably 750%, and more preferably 700%.

  The film forming the base material layer 1 may be a single layer or a plurality of layers. When a film composed of a plurality of layers is used, a coextruded film is suitable. This coextruded film is preferably one in which at least one of the front surface and the back surface is made of a polyolefin resin. By forming the base material layer 1 with the coextruded film having such a configuration, the base material layer 1 can be sufficiently prevented from being damaged or torn. In addition, from the viewpoint of preventing alteration of the contents of the spout container 10, the base material layer 1 has at least two polyolefin resin layers and a resin layer provided between the polyolefin resin layers and having gas barrier properties. It is preferable. The thickness of the base material layer 1 is preferably 10 to 200 μm, and more preferably 15 to 80 μm.

  Specific configurations of the base material layer 1 include, for example, polyethylene / EVOH / polyethylene, polyethylene / nylon / EVOH / polyethylene, polyethylene / nylon / EVOH / nylon / polyethylene, polyethylene / PETG / nylon / EVOH / polyethylene, polyethylene / EVOH / nylon / polyethylene, polyethylene / MXD nylon 6 / polyethylene, polyethylene / nylon / mosa nylon 6 / nylon / polyethylene, polypropylene / EVOH / nylon / polypropylene, polypropylene / nylon / EVOH / nylon / polypropylene, polypropylene / MXD nylon 6 / polypropylene , Etc. EVOH means ethylene-vinyl alcohol copolymer, and PETG means non-crystalline PET (polyethylene terephthalate) copolymer.

  As the sealant layer 2, a film having a tensile elongation of 500 to 1000% is used. If the tensile elongation of the sealant layer 2 is less than 500%, the tensile elongation of the laminated film 5 becomes insufficient. The lower limit of the tensile elongation of the sealant layer 2 is preferably 550%, and more preferably 600%. On the other hand, a sealant layer having a tensile elongation exceeding 1000% may be difficult to process. The upper limit of the tensile elongation of the sealant layer 2 is preferably 950%, and more preferably 900%. When the tensile elongation of the sealant layer 2 is larger than the tensile elongation of the base material layer 1, the spout bonding surface side of the laminated film is more likely to follow the spout shape, and the bonding degree between the laminated film and the spout is more preferable. .

  The film forming the sealant layer 2 may be a single layer, but is preferably a coextruded film composed of a plurality of layers. From the viewpoint of weldability between the container body 7 and the spout 8, this coextruded film is preferably one in which at least one of the front surface and the back surface is formed of a polyolefin resin. Moreover, it is preferable that the film which forms the sealant layer 2 contains a thermoplastic elastomer having flexibility from the viewpoint of formability. As the polyolefin resin, polyethylene, polypropylene and the like are selected. Examples of thermoplastic elastomers include styrene block copolymers (TPE-S such as SEPS, SIS, SEBS, and SBS), polyetheresters (TPE-S), polyurethane (TPU-U), and polyetheramide (TPE-A). It is selected from a group including or a group including EPDM. The thickness of the sealant layer 2 is preferably 10 to 200 μm, and more preferably 30 to 150 μm.

  TPE simply abbreviates thermoplastic elastomer. SEBS means styrene-ethylene / butylene-styrene triblock polymer, SBS means styrene-butylene-styrene diblock polymer, and SEPS means styrene-ethylene / propylene-styrene triblock polymer. , SIS means styrene-isoprene-styrene triblock polymer. EPDM means a terpolymer composed of at least one of ethylene and propylene and a copolymer of diene (EPDM) or ethylene-alpha olefin which is not a conjugated double bond.

  Specific examples of the sealant layer 2 include polyethylene / SEPS / polyethylene, polyethylene / SEBS / polyethylene, polyethylene / EPDM / polyethylene, polypropylene / SEPS / polypropylene, polypropylene / EPDM / polypropylene, and a blend of polyethylene / polyethylene and SEPS. Resin / polyethylene, polyethylene / polyethylene and SEBS blend resin / polyethylene, polyethylene / polyethylene and EPDM blend resin / polyethylene, polypropylene / polypropylene and SEPS blend resin / polypropylene, polypropylene / polypropylene and EPDM blend resin / polypropylene, etc. is there.

  The bonding layer 3 is a layer for bonding the base material layer 1 and the sealant layer 2 together. The bonding layer 3 is formed between the base material layer 1 and the sealant layer 2 by extrusion lamination. When carrying out the extrusion lamination, the thickness of the bonding layer 3 is adjusted to be within a predetermined range. From the viewpoint of extrusion lamination processing characteristics and interfacial adhesion, the thickness of the bonding layer 3 is preferably 5 to 30 μm, more preferably 7 to 25 μm, and still more preferably 8 to 20 μm.

  Examples of the resin used for extrusion lamination include polyolefin resins such as polypropylene and polyethylene. The polyolefin resin may contain an additive that is blended as necessary. Examples of the additive include a stabilizer, a neutralizing agent, an antistatic agent, a plasticizer, a lubricant, an antioxidant, and an antiblocking agent. These additives may be used alone or in combination of two or more.

  The laminated film 5 in which the base material layer 1 and the sealant layer 2 are joined by the joining layer 3 has a high tensile elongation. Even if one of the base material layer 1 and the sealant layer 2 has a lower tensile elongation than the other, the resulting laminated film 5 has a higher tensile elongation than the tensile elongation of the one layer. Can be. This is because the bonding layer 3 is interposed between the base material layer 1 and the sealant layer 2 so that the local breakage is caused as compared with the case where the base material layer 1 or the sealant layer 2 is subjected to a tensile test alone. This is presumed to be suppressed. The tensile elongation of the laminated film 5 may be appropriately designed according to the size and use of the spout container 10, but is preferably 500 to 1000%, more preferably 550 to 950%.

  In addition, the bonding strength between the base material layer 1 and the sealant layer 2 can be adjusted to a desired level by appropriately setting the thickness or composition of the bonding layer 3. For example, the bonding strength between the base material layer 1 and the sealant layer 2 can be compared by reducing the thickness of the bonding layer 3 to 8 to 20 μm, or by lowering the resin extrusion temperature when the bonding layer 3 is processed. Can be set low. In this case, while using the spout container 10, the base material layer 1 (outer layer) and the sealant layer 2 (inner layer) are peeled off (except for the heat seal portion 7a shown in FIG. 2) to form a double bag. The double bag spout container 10 has a gap between the base material layer 1 and the sealant layer 2. For example, even if a hole is formed in the base material layer 1, there is an advantage that the sealant layer 2 can maintain hermeticity. is there.

<Spout container>
Next, the spout container 10 shown in FIG. 2 will be described. The spout container 10 has a container body part 7 formed by processing the laminated film 5 into a bag shape with the sealant layer 2 on the inside, and a flow path that communicates the inside and the outside of the container body part 7. 7 and a spout 8 attached to the peripheral edge of 7. As shown in FIG. 2, the laminated film 5 is processed into a bag shape by forming a heat seal portion 7 a at the peripheral portion of the container main body portion 7. The spout 8 has a cylindrical portion 8 a and a joint portion 8 b provided below the spout 8. The outer peripheral surface of the joint portion 8 b and the container body portion 7 are bonded together, and the cylindrical portion 8 a protrudes outside the container body portion 7. To be attached. The spout 8 can be fitted with a cap 9 on the tip side of the cylindrical portion 8a.

  3A and 3B are a perspective view and a plan view showing an example of a spout. As the spout 8, one produced by an injection molding method or the like can be used. Examples of the material of the spout 8 include synthetic resins such as polyethylene and polypropylene. As a cross-sectional shape of the joint portion 8b with the container main body portion 7, a circular shape, an elliptical shape, or a polygonal shape can be cited in addition to the shape shown in FIG. In the spout 8, it is preferable that the inner diameter A of the flow path is 20 mmφ or more from the viewpoint of fluidity and filling suitability of the packing (see FIG. 3A). In this case, the outer periphery C of the joint 8b with the film of the spout 8 is 70 mm or more, although depending on the outer diameter B of the spout 8 and the shape of the joint 8b (see FIG. 3B). Although the length of the outer periphery C of the junction part 8b should just be designed suitably according to the size and use of the spout container 10, it is preferable that it is 80-1000 mm, and it is more preferable that it is 100-500 mm.

  Welding of the container body 7 and the spout 8 can be performed by a heated gas, electric heat, hot air, a micro frame, ultrasonic waves, or the like. Since the spout container 10 thus produced has high sealing properties, it can be filled with liquids such as soft drinks, alcoholic beverages, soy sauce, salad oil, and liquid detergents. Alternatively, the spout container 10 may be filled with powder or granular material. In addition, when filling with a powder, a granular material, etc., you may evacuate the inside of the spout container 10. In order to increase the bonding area between the spout 8 and the film, a protrusion that extends in the direction of the container body 7 from the lower end of the bonding portion 8b may be provided. By providing such a protruding portion, it is possible to prevent the opening of the spout 8 from being blocked by the laminated film 5 evacuated. Since the laminated film 5 has a high tensile elongation, even when the laminated film 5 is pressed against the protruding portion by evacuation, it is possible to sufficiently prevent a hole from being opened at the location.

  As described above, by forming the container main body portion 7 of the spout container 10 with the laminated film 5, it is possible to achieve high sealing performance at the welding location. Further, by using the laminated film 5 having a high tensile elongation, even when a spout having a relatively large diameter and a spout having a long outer periphery of the joint portion or a spout having a large outer diameter of the joint portion is used, high sealing performance is achieved. Can be produced.

Hereinafter, the present invention will be described using examples and comparative examples. Each item in Examples and Comparative Examples was measured or evaluated by the following method.
(1) Film thickness The thicknesses of the base material layer, sealant layer and spout container laminated film were measured using a dial gauge.
(2) Tensile test (tensile elongation, tensile modulus)
Measurement was performed in accordance with JIS K7127. First, a strip sample having a width of 15 mm and a length of 200 mm was prepared. Both ends of this sample were each attached to a tensile tester so that the distance between chucks was 50 mm. The chuck was moved at a moving speed of 50 mm / min between the chucks, and the maximum load and the maximum elongation until breaking required at that time were measured to obtain the tensile strength and the tensile elongation. The load at 0.3% elongation was defined as the tensile elastic modulus.
(3) Weldability between container body and spout Laminated film is cut into A4 size (210mm x 297mm), and a piece of film is pasted to form a bottom with a width of 10mm between the two films. The container body was made by pasting together leaving one side into a bag shape. On the other hand, three types of spouts (outer diameter 65.6 mm (outer diameter 20 mm, inner diameter 15 mm), outer circumference 82.5 mm (outer diameter 25 mm, inner diameter 20 mm), outer circumference 147. 3 mm (outer diameter 45 mm, inner diameter 40 mm) was prepared. Using a hot air jet unit (manufactured by Weldy), spout was welded to the container body with hot air at 160 ° C. to prepare a spout container. The weldability of the weld location and the sealability of the spout container were evaluated based on the following criteria.
(3-1) Water leakage from welded spot ○: After filling 1 L of water in the spout container, there was no water leak from the welded spot.
X: After filling 1 L of water into the spout container, there was water leakage from the welded part.
(3-2) Compressive strength test Measurement was performed according to JIS Z238. Using a pressure tester (Stroke V20-C, manufactured by Toyo Seiki Seisakusho), apply a compression load at a compression speed of 5 mm / min to the spout container that did not leak in (3-1), The maximum point load at which water leakage occurred was measured.

(Example)
A polyethylene / EVOH / polyethylene co-pressed film (thickness 70 μm) was used as the base material layer, and a polyethylene / polyethylene / SEBS blend resin / polyethylene co-pressed film (thickness 60 μm) was used as the sealant layer. A melt-extruded resin layer (bonding layer, thickness 9 μm) was laminated between the base material layer and the sealant layer to obtain a laminated film. A linear low density polyethylene resin (density: 0.915 g / cm ³ , MI: 7 g / 10 min) was used as the melt-extruded resin. Table 1 shows the film physical properties of this laminated film.

  The laminated film obtained as described above was processed into a bag-like container body. A spout was prepared by inserting a spout into the opening of the container body and heat-sealing with a hot air jet unit. Table 2 shows the evaluation results of the weldability between the container body and the spout and the sealability of the spout container.

(Comparative example)
A biaxially stretched nylon film (thickness 15 μm) was used as the base material layer, and a polyethylene film (thickness 60 μm) was used as the sealant layer. A 3 g / m ² polyester polyurethane adhesive was applied to one surface of the base material layer as a bonding layer, and a sealant layer was laminated on the coated surface, thereby laminating by a dry lamination method. Table 1 shows the film physical properties of this laminated film.

  Using the obtained laminated film, a spout container was prepared in the same manner as in the above example, and then a spout container was prepared. Table 2 shows the evaluation results of the weldability between the container body and the spout and the sealability of the spout container.

  As shown in Tables 1 and 2, it can be seen that the examples satisfying the requirements of the present invention are excellent in weldability and sealing performance even when a spout having an outer periphery of 82.5 mm or more is used. On the other hand, it can be seen that the comparative example that does not satisfy the requirements of the present invention has insufficient weldability and sealability when a spout having an outer periphery of 82.5 mm or more is used.

It is a schematic cross section which shows one Embodiment of the laminated film for spout containers which concerns on this invention. It is a perspective view showing one embodiment of a spout container concerning the present invention. (A) And (b) is the perspective view and top view which show an example of a spout.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Base material layer, 2 ... Sealant layer, 3 ... Joining layer, 5 ... Laminated film for spout containers, 7 ... Container main-body part, 7a ... Heat seal part, 8 ... Spout, 8a ... Cylindrical part, 8b ... Joining part, 9 ... cap, 10 ... spout container, C ... outer periphery of the joint.

Claims (9)

A base material layer having a tensile elongation of 400 to 800%,
A sealant layer having a tensile elongation of 500 to 1000%;
Formed between the base material layer and the sealant layer by extrusion lamination, a bonding layer that bonds the base material layer and the sealant layer;
A laminated film for a spout container.   The laminated film according to claim 1, wherein the base material layer is composed of a plurality of layers formed by coextrusion, and at least one of the front surface and the back surface is formed of a polyolefin-based resin.   The laminated film according to claim 1 or 2, wherein the base material layer has at least two polyolefin resin layers and a resin layer provided between the polyolefin resin layers and having gas barrier properties.   The laminated film according to any one of claims 1 to 3, wherein a tensile elongation of the sealant layer is larger than a tensile elongation of the base material layer.   The said sealant layer is a laminated | multilayer film as described in any one of Claims 1-4 containing an olefin resin or / and a thermoplastic elastomer.   The laminated film according to claim 1, wherein the bonding layer contains a polyethylene resin or a polypropylene resin.   The thickness of the said joining layer is a laminated film as described in any one of Claims 1-6 which is 5-30 micrometers. A container main body formed by processing the laminated film according to any one of claims 1 to 7 into a bag shape with the sealant layer inside,
A spout having a flow path communicating between the inside and the outside of the container main body, and attached to a peripheral edge of the container main body;
A spout container comprising:   The spout container of Claim 8 whose outer periphery of the junction part with the said container main-body part in the said spout is 70 mm or more.

Images