Spout and packaging container

Abstract

To provide a spout suitably used for manufacturing a packaging container while reducing the used amount of plastic.SOLUTION: In a spout 1 formed into a cylindrical shape and having a junction 2 at one end for joining a pouch, the junction has a shape horizontally extending and gradually smaller in size in a cross direction toward the horizontal end, and a groove 103 formed on the outer surface. A contact surface is formed along one surface of the outer shape of the junction, the junction is placed on the contact surface of a fixture made of a material more rigid than that of the spout, a probe having a circular pressing surface of a diameter 15 mm is brought into contact to press it from above, and a compression strength at the time when the probe moves down by 3 mm is 318 Newton or greater.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a spout and also to a packaging container using the spout. [Background technology]

[0002] 2. Description of the Related Art Packaging containers that have a spout attached to a pouch formed from a resin film to facilitate pouring of the contents are widely known (see, for example, Patent Document 1). A typical spout is produced by injection molding using a synthetic resin. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-117044 A Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, efforts to reduce the amount of plastic used have been underway in various fields in order to reduce the environmental impact. The inventors, in an attempt to reduce the amount of plastic used in spouts, discovered a new problem in the manufacture of packaging containers that had not been clarified until now, and completed the present invention.

[0005] An object of the present invention is to provide a spout that can reduce the amount of plastic used while also being suitable for use in the manufacture of packaging containers. [Means for solving the problem]

[0006] A first aspect of the present invention is a spout that is formed in a cylindrical shape and has a joint at one end for joining to a pouch. The joint portion extends in the left-right direction, and has a shape whose dimension in the front-rear direction gradually decreases toward the left-right ends, and has a groove formed in the outer surface. The joint of the spout is placed on the contact surface of a jig made of a material more rigid than the spout, and has a contact surface that conforms to one side of the outer shape of the joint. A probe with a circular pressing surface with a diameter of 15 mm is then placed in contact from above and pressed; when the probe has moved 3 mm downward, the compressive strength is 318 Newtons or more.

[0007] A second aspect of the present invention is a packaging container comprising the spout according to the first aspect and a pouch to which the spout is attached. In this packaging container, the joint of the spout is attached to the pouch by heat sealing. Effect of the Invention

[0008] The packaging container according to the present invention can be deformed into a shape suitable for consumption by unfolding, and can ensure a large volume when deformed. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 shows a typical spout. [Diagram 2] FIG. 2 shows a spout attached to a pouch. [Diagram 3] FIG. 13 shows a spout with a reduced amount of resin. [Figure 4] FIG. 13 shows a pouch with resin protrusion. [Diagram 5] 13(a) and 13(b) are diagrams for explaining the mechanism by which resin extrusion occurs. [Figure 6] FIG. 2 shows a spout according to one embodiment of the present invention. [Figure 7] FIG. 11 is a diagram showing another example of the spout. [Figure 8] FIG. 1 is a diagram showing a process of measuring the compressive strength of a joint. [Figure 9] 13(a) and (b) are views of a joint according to a modified example of the spout as viewed from below. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] A first embodiment of the present invention will be described with reference to FIGS. Figure 1 shows a typical spout 100. The left side of Figure 1 is a front view of the spout 100, and the right side is a bottom view of the spout 100. The spout 100 has a basic cylindrical structure and has a screw 101 for attaching a cap at one end. The other end is provided with a joint 102 for joining to a container body such as a pouch. As shown in the bottom view on the right side, the joint 102 extends in the left-right direction of the spout 100 and has a shape in which the dimension in the front-rear direction gradually becomes thinner as it approaches the left and right ends. This type of shape is also called a spindle shape or a boat shape.

[0011] When spout 100 is attached to a pouch, the front and rear films constituting the pouch are arranged to sandwich joint 102, and are sandwiched with a heat seal bar to apply heat and pressure. In this way, where the front and rear films are in contact with each other, the sealant layers of the films are bonded by heat fusion, and where joint 102 is sandwiched between them, the sealant layers of the films and joint 102 are bonded by heat fusion. In this way, spout 100 can be attached to the periphery of pouch 110, as shown in Fig. 2, and a packaging container equipped with the spout and pouch is completed. Since spout 100 communicates with the internal space of pouch 110, the contents can be filled or poured through the spout.

[0012] In spout 100, the cylindrical portion including joint 102 has a non-uniform wall thickness due to the shape of joint 102. That is, as shown in the bottom view of Fig. 1, the wall thickness is smallest at the front and rear sides of joint 102 and is larger in other areas.

[0013] The inventors noticed that due to such a shape of joint 102, even if a part of joint 102 is removed, the thickness can be secured to be equal to that of the front and rear sides of joint 102. Then, as shown in Fig. 3, by forming a plurality of grooves 103 on the outer peripheral surface of joint 102, they succeeded in forming joint 102A having a smaller amount of resin than joint 102.

[0014] However, when a spout having joint 102A was attached to pouch 110 under similar conditions, the spout and pouch were joined without any problems, but resin overflow 120 was observed where the front film and the rear film were in contact, as shown in Figure 4.

[0015] The inventors have studied this phenomenon and found that the main cause is that the rigidity of joint 102A, in which the amount of resin has been reduced, is significantly reduced compared to joint 102 before the reduction. The details are as follows. When heat and pressure are applied by the heat seal bar, the joint 102A cannot fully withstand the pressure, and as a result, it is slightly compressed and deformed in the front-rear direction of the pouch, and the dimension of the joint 102A in the front-rear direction of the spout is reduced. Due to the compressive deformation of the joint 102A, the front film, the rear film, and the heat seal bar opposing each other across the joint 102A can be closer than when the joint 102 is joined, and the distance between the heat seal bars is reduced.

[0016] The distance between the heat seal bars at the contact points between the front and rear films is usually set to be approximately equal to the sum of the thicknesses of the front and rear films. Therefore, when the joint 102 is normally joined, as shown in FIG. 5(a), the front film 111 and the rear film 112 are in contact with each other without any gaps in an uncompressed state, and are heat-sealed. However, as described above, when the distance between the heat seal bars is reduced due to the compressive deformation of the joint 102A, the distance becomes smaller than the sum of the thicknesses of the front and rear films. As a result, the particularly soft sealant layer 113 of the front and rear films 111 and 112 is compressed. Finally, a portion of the molten sealant layer 113 that cannot be contained becomes protruding 120.

[0017] Since a general heat sealing device is not configured to monitor or control the pressure applied to the object by the heat seal bar, it is difficult for the heat sealing device to suppress this overflow. Therefore, the inventors have studied the conditions of the joint that can sufficiently prevent the occurrence of overflow 120 while reducing the amount of resin.

[0018] An example of a spout according to this embodiment is shown in Figure 6. The spout 1 shown in Figure 1 has a basic cylindrical structure with an internal space extending in the vertical direction, and has a screw 101 at one end and a joint 2 at the other end. The external shape of joint 2 is generally similar to that of joint 102A described above, and the form of groove 103 is also similar. However, diameter D1 of the cylindrical internal space in the joint is smaller than diameter D in joint 102A (see FIG. 1. The diameter in joint 102A is the same as the diameter in joint 102). As a result, the amount of resin that can be reduced is slightly less than in joint 102A, while the minimum thickness of the joint is greater than in joint 102A.

[0019] Another example of a spout according to this embodiment is shown in Figure 7. A spout 1A shown in Figure 1 has the same structure as spout 1, except that a joint 2A is provided instead of joint 2. The joint 2A has a vertical rib 3 in the groove 103. This allows the amount of resin that can be reduced to be slightly less than that of the spout 1, while at the same time improving the compressive strength of the joint.

[0020] The compressive strength of the joint was measured for three types of spouts, namely, the spouts 1 and 1A described above, and a spout having joint 102A and causing protrusion. The measurement procedure is described below. First, five of each of the above-mentioned spouts were produced by injection molding using high density polyethylene (HDPE).

[0021] Next, a jig for installing the spout was prepared. The jig 200 shown in FIG. 8 has a first support part 201 that supports the vicinity of the screw 101 and a second support part 202 that supports the joint part, and is formed of a material with higher rigidity than the material of the spout. In the first support part 201 and the second support part 202, the shape of the contact surface that contacts the spout is a shape that follows the outer shape of the part of the spout that contacts it, that is, it is almost the same as the outer surface of the part without the screw and the joint part without the groove. Such a jig 200 can be made by cutting or casting, but since resins such as "PP-like resin" used in 3D printers are harder than HDPE, it is easy to make it with a 3D printer using these resins. An example of PP-like resin is "RIGUR RGD450" manufactured by Stratasys. The spout is placed on jig 200 so that the left-right direction coincides with the horizontal direction. There are no limitations on the specific shape or dimensions of jig 200, so long as the left-right direction coincides with the horizontal direction when the spout is supported by first support portion 201 and second support portion 202, the contact surface of second support portion 202 contacts the joint over 50% or more of the joint in the up-down direction, and the jig can stably support the spout. If the outer shape of the joint differs between the front and rear sides, the above condition only needs to be satisfied on at least one of the outer surfaces.

[0022] Next, the probe 300 of the compressive strength measuring device was brought close from above the joint and brought into contact with the joint. The probe 300 was then pressed down until it descended 3 mm, and the force at which the probe 300 descended 3 mm was used as the compressive strength. The pressure surface 300a of the probe was a circle with a diameter of 15 mm, and the descending speed was 20 mm / min. The measurement results for each example are shown in Table 1. In Table 1, the spout without groove 103 causing protrusion is represented as "Comparative Example", spout 1 as "Example 1", and spout 1A as "Example 2".

[0023] [Table 1]

[0024] As shown in Table 1, the compressive strength of all the samples in the Examples exceeded the maximum value of the Comparative Examples. After the measurements, the samples were heat-sealed to a pouch under the same heat and pressure conditions. All the Comparative Examples showed extrusion, whereas none of the Examples showed extrusion. From the above results, it was found that the minimum strength of the joint required to prevent extrusion was between the maximum value of approximately 300 Newtons (N) in the comparative example and the minimum value of approximately 337 N in the embodiment, and was estimated to be roughly halfway between the two, at around 318 N.

[0025] As described above, according to this embodiment, the joint has sufficient compressive strength, which makes it possible to advantageously reduce the amount of resin while preventing the sealant layer from protruding when attached to the pouch.

[0026] In this embodiment, the means for imparting compressive strength to the joint is not limited to the above-mentioned embodiment. For example, instead of reducing the diameter of the internal space, only a part of the inner surface may be protruded. Furthermore, as shown in FIG. 9(a), the protruding portion may be extended to form a support 4 extending in the front-rear direction of the spout. Although this slightly affects the flow of the contents in and out, if the contents are liquid, fine powder, or the like, the strength of the joint can be improved without substantial effects. As a further modification, a plurality of support columns may be provided, or reinforcing walls 5 extending in the left-right direction of the spout may be combined as shown in FIG. 9(b).

[0027] Each embodiment of the present invention has been described above with reference to experimental examples. However, the specific configurations are not limited to these embodiments, and modifications and combinations of the configurations that do not depart from the gist of the present invention are also included.

[0028] For example, the material of the spout according to the present embodiment is not limited to the above-mentioned HDPE. However, in the case of a spout that is heat-sealed to a pouch, the material is generally polyolefin, and HDPE and polypropylene are generally materials with higher rigidity. Therefore, in this field, it is practically difficult to increase the rigidity of the joint by changing the material, so the technical significance of the present invention is extremely great.

[0029] Furthermore, the grooves for reducing the amount of resin are not limited to those extending in the left-right direction as described above, but may extend in other directions such as the up-down direction. [Explanation of symbols]

[0030] 1, 1A spout 2, 2A joint 103 Groove 110 pouch 200 Jig 300 Probe 300a Pressing surface

Claims

1. A spout formed in a cylindrical shape and having a joint at one end for joining to a pouch, The joint is The shape extends in the left-right direction and has a gradually decreasing dimension in the front-rear direction toward the left-right ends, A groove is formed on the outer surface. The joint is placed on the contact surface of a jig formed of a material having a contact surface conforming to one side of the outer shape of the joint and having a higher rigidity than the spout, and a measuring probe having a circular pressing surface having a diameter of 15 mm is brought into contact with the joint from above and pressed against the joint. When the measuring probe is moved downward by 3 mm, the compressive strength is 318 Newtons or more. Spout.

2. The compressive strength is 337 Newtons or more. The spout of claim 1.

3. Made from high density polyethylene, The spout of claim 1.

4. A spout according to any one of claims 1 to 3; a pouch to which the spout is attached; and Equipped with The joint is attached to the pouch by heat sealing. packaging container.

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