Plug, and pouch with plug

Abstract

To prevent any hole from being opened in a film in the vicinity of a plug.SOLUTION: A plug 10 made of high density polyethylene used in a pouch includes a flow channel 11 extending in a first direction D1, a pour-out part 12 which extends in the first direction D1 and forms a part of the flow channel 11, and a welding part 13 which extends in the first direction D1 and forms other part of the flow channel 11, wherein the welding part 13 has such a shape that thickness in a third direction D3 becomes smaller toward the end in a second direction D2 from the central part in the second direction D2. When an indenter 52 is pushed to the welding part 13 by 4.5 mm in the third direction D3, in a predetermined region exceeding a yield point of the welding part 13, an inclination S of a value obtained by dividing a load F of the indenter 52 by a contact area A between the welding part 13 and the indenter 52 to a push-in amount X of the indenter 52 is 1.70 N / mm3 or less.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a spout for use in a pouch and a spout-equipped pouch provided with said spout. [Background technology]

[0002] Conventionally, spouted pouches, in which a resin spout is welded to a pair of resin films, have been used as containers for accommodating liquids or other contents. In spouted pouches, a heated seal bar is pressed against the spout from above the film to melt the sealant layer of the film and the spout, thereby welding the film to the spout. Patent Document 1 describes a spout made of high-density polyethylene as the spout for such a spouted pouch. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2018-536591 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, efforts have been made to make packaging materials mono-material in order to improve recyclability. The present inventors therefore produced plugs made of high-density polyethylene and evaluated the weldability between these plugs and polyethylene-based films, and found that some plugs caused holes in the film near the plug.

[0005] Therefore, an object of the present invention is to provide a stopper made of high-density polyethylene that can prevent holes from being made in the film near the stopper, and a stoppered pouch equipped with said stopper. [Means for solving the problem]

[0006] The present inventors have further studied the above problem and have found the following. That is, when a seal bar is pressed against the plug from above the film in order to weld the film to the plug, the film may be overheated. In such a case, since polyethylene has a relatively low melting point and a high thermal shrinkage rate, the film undergoes a large thermal shrinkage while melting. At this time, the plug tries to deform to follow the thermal shrinkage of the film. However, it was found that if the plug is difficult to deform, the deformation of the plug cannot follow the thermal shrinkage of the film, and a hole may be formed in the film near the plug. From this, it was found that by making the plug easy to deform, it is possible to suppress the film from being perforated near the plug even if the film is overheated by the seal bar being pressed against the welded portion from above the film. The present invention has been made based on the above findings.

[0007] [1] A plug according to the present invention is a plug made of high-density polyethylene for use in a pouch, comprising a flow path extending in a first direction, a pouring portion extending in the first direction to form a part of the flow path, and a welded portion extending in the first direction to form another part of the flow path, wherein the welded portion has a shape in which its thickness in a third direction perpendicular to the first and second directions decreases from a central portion in a second direction perpendicular to the first direction to an end portion in the second direction, and wherein when an indenter is pressed 4.5 mm into the welded portion in the third direction, the slope of the value obtained by dividing the load of the indenter by the contact area between the welded portion and the indenter relative to the amount of pressing of the indenter in a predetermined region beyond the yield point of the welded portion is 1.70 N / mm 3 The following is the result.

[0008] In this plug, the welded portion has a complex shape in which the thickness in the third direction decreases from the center in the second direction toward the end in the second direction, so that when the seal bar is pressed against the welded portion from above the film, the film is likely to be locally overheated. However, in a specified region beyond the yield point of the welded portion, the slope of the value obtained by dividing the load of the indenter by the contact area between the welded portion and the indenter relative to the amount of indenter pressing is 1.70 N / mm 3Therefore, even if the film is overheated by the seal bar being pressed against the welded portion from above the film, the welded portion will deform to follow the thermal contraction of the film, thereby preventing holes from being formed in the film near the spout.

[0009] [2] In the plug described in [1] above, the welded portion may have a base and a rib protruding from the base. In this plug, since the welded portion has a rib protruding from the base, the contact area between the welded portion and the film is small when the seal bar is pressed against the welded portion from above the film, making the film more likely to be locally overheated. However, when the inclination is 1.70 N / mm 3 Since the welded portion is deformed to follow the thermal shrinkage of the film, it is possible to prevent holes from being formed in the film near the spout.

[0010] [3] In the plug described in [1] or [2] above, the welded portion may have a base and a groove recessed from the base. In this plug, since the welded portion has a groove recessed from the base, the contact area between the welded portion and the film is small when the seal bar is pressed against the welded portion from above the film, making the film more likely to be locally overheated. However, when the inclination is 1.70 N / mm 3 Since the welded portion is deformed to follow the thermal shrinkage of the film, it is possible to prevent holes from being formed in the film near the spout.

[0011] [4] The spouted pouch according to the present invention comprises a pouch body having a pair of films, and the spout according to any one of [1] to [3] above, which is disposed between the pair of films and welded to the pair of films, each of which has a sealant layer containing polyethylene on its innermost surface. In this spouted pouch, the spout is welded to the pair of films, so that even if the film is locally overheated during the manufacture of the spouted pouch by pressing a seal bar against the welded portion of the spout from above the film, the welded portion deforms to follow the thermal shrinkage of the film, thereby preventing holes from being formed in the film near the spout. This makes it possible to prevent holes from being formed in the film. Effect of the Invention

[0012] According to the present invention, it is possible to suppress the formation of holes in the film near the plug. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a front view showing a spouted pouch according to an embodiment. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing a portion of the body film. [Diagram 3] FIG. 2 is a diagram showing an example of a DSC curve obtained by differential scanning calorimetry of a stopper. [Figure 4] FIG. 2 is a front view showing the plug according to the embodiment. [Diagram 5] FIG. 2 is a side view showing the plug according to the embodiment. [Figure 6] FIG. 2 is a bottom view showing the plug according to the embodiment. [Figure 7] FIG. 13 is a front view showing a state in which a push-in test is being performed. [Figure 8] 1 is a graph showing the measurement results of an indentation test. [Figure 9] FIG. 13 is a diagram for explaining a contact area. [Figure 10] FIG. 13 is a front view showing a modified plug. [Figure 11]FIG. 13 is a side view showing a modified plug. [Figure 12] FIG. 13 is a bottom view showing a modified example of the plug. [Figure 13] 13 is a diagram for explaining a contact area in a plug of a modified example. FIG. [Figure 14] FIG. 13 is a front view showing a plug of another modified example. [Figure 15] FIG. 11 is a side view showing a plug of another modified example. [Figure 16] FIG. 13 is a bottom view showing a plug of another modified example. [Figure 17] 13A and 13B are diagrams for explaining a contact area in another modified example. [Figure 18] 1 is a graph plotting the measurement results of an indentation test in Examples 1 and 2 and Comparative Example 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding elements are designated by the same reference numerals, and duplicated description will be omitted.

[0015] (Pouch with stopper) FIG. 1 is a front view showing a spouted pouch according to an embodiment. The spouted pouch 1 shown in FIG. 1 is used for refilling contents into a container (not shown) such as a refill bottle, packaging beverages, packaging cosmetics, and the like. FIG. 2 is a cross-sectional view taken along line II-II shown in FIG. 1. As shown in FIGS. 1 and 2, the spouted pouch 1 according to the embodiment includes a pouch body 2 and a spout 3. The spout is also called a spout or the like. The pouch body 2 includes a pair of resin films, a first body film 4A and a second body film 4B, opposed to each other, and a resin folding film 5 folded between the first body film 4A and the second body film 4B. The pouch body 2 may not include the folding film 5, or may further include another film.

[0016] The first and second body films 4A and 4B are heat-sealed (welded) to each other at their outer edges so as to form a storage area 6 for storing contents inside the spouted pouch 1, and the first and second body films 4A and 4B are heat-sealed to each other at their outer edges with the fold-out film 5. A spout 3 is disposed between the first and second body films 4A and 4B, and the outer edges of the first and second body films 4A and 4B are heat-sealed to the spout 3. The first and second body films 4A and 4B have the same shape, structure, etc. and are heat-sealed to the spout 3, and therefore, hereinafter, the first and second body films 4A and 4B will be collectively described as the body film 4 unless otherwise specified.

[0017] The trunk film 4 is formed of a laminate sheet in which a base layer 7 and a sealant layer 8 are laminated. The sealant layer 8 forms the innermost surface of the trunk film 4. In other words, the trunk film 4 has the sealant layer 8 on its innermost surface. The laminate sheet constituting the trunk film 4 may include layers other than the base layer 7 and the sealant layer 8. For example, the laminate sheet constituting the trunk film 4 may include a barrier layer disposed between the base layer 7 and the sealant layer 8.

[0018] The base layer 7 provides a predetermined rigidity to the body film 4 and has a barrier property that prevents the passage of gas and liquid. The material of the base layer 7 is not particularly limited, but may be, for example, polyolefin (e.g., polyethylene, very low density polyethylene, low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, or polypropylene) or polyester (e.g., polyethylene terephthalate). The density of very low density polyethylene is 0.900 g / cm. 3 The density of low density polyethylene is less than 0.900 g / cm 3 More than 0.925g / cm 3 The density of linear low density polyethylene is less than 0.900 g / cm 3 More than 0.925g / cm3 The density of medium density polyethylene is less than 0.925 g / cm 3 More than 0.945g / cm 3 The density of high density polyethylene is less than 0.945 g / cm 3 or more than 0.945g / cm 3 More than 0.980g / cm 3 The following is the result.

[0019] The sealant layer 8 is a layer that can be melted to be welded to the plug 3. In other words, the sealant layer 8 is a layer that can be heat-sealed. The sealant layer 8 contains polyethylene. The polyethylene contained in the sealant layer 8 is not particularly limited, and can be, for example, very low density polyethylene, low density polyethylene, linear low density polyethylene, medium density polyethylene, or high density polyethylene. Furthermore, the sealant layer 8 may contain polypropylene, polyester (e.g., polyethylene terephthalate), or the like, in addition to polyethylene.

[0020] The contents accommodated in the accommodation area 6 of the spouted pouch 1 are not particularly limited, but are preferably liquids. Examples of the contents include daily necessities such as liquid detergents, cleaning agents, medicines, cosmetics, shampoos, and conditioners, liquid seasonings, foods such as soups, yogurt, soft drinks, and edible oils, and industrial products such as lubricating oils and industrial oils. The spouted pouch 1 may be a pouch with a contents inlet plug in which the contents are accommodated in the accommodation area 6.

[0021] The plug 3 is made of high density polyethylene. Made of high density polyethylene means that the material constituting the plug 3 mainly contains high density polyethylene, and may contain other polymers such as medium density polyethylene and low density polyethylene, additives, etc. The weight percentage of high density polyethylene in the plug 3 is, for example, 80% or more, preferably 90% or more, and more preferably 95% or more.

[0022] In this embodiment, the melting point of the plug 3 is the temperature indicated by the apex of the endothermic peak in the DSC curve. That is, the temperature indicated by the apex of the endothermic peak in the DSC curve obtained by differential scanning calorimetry is defined as the melting point of the plug 3. The endothermic peak is a peak of heat absorption due to melting, and is also called a melting peak.

[0023] FIG. 3 is a diagram showing an example of a DSC curve obtained by differential scanning calorimetry of a plug. In FIG. 3, the vertical axis shows the heat flow of endotherm in an upward direction. In the example shown in FIG. 3, the temperature indicated by the apex P of the endothermic peak of the DSC curve is the melting point of the plug 3. The melting point of the plug 3 may be, for example, 130.0°C or lower, or 129.0°C or lower. The lower limit of the melting point of the plug 3 is not particularly limited, but may be, for example, 125.0°C or higher, or 127.0°C or higher.

[0024] The spout 3 has a flow path 31 for distributing the contents accommodated in the pouch body 2, a pouring portion 32 disposed on the outside of the pouch body 2 and forming a part of the flow path 31, a welded portion 33 welded to the body film 4 and forming another part of the flow path 31, and a flange portion 34 located between the pouring portion 32 and the welded portion 33. Details of the spout 3 will be described later.

[0025] (Plug) Next, the plug according to the embodiment will be described. Fig. 4 is a front view showing the plug according to the embodiment. Fig. 5 is a side view showing the plug according to the embodiment. Fig. 6 is a bottom view showing the plug according to the embodiment. As shown in Figs. 4 to 6, the plug 10 according to the embodiment is a plug that becomes the plug 3 of the spouted pouch 1 shown in Figs. 1 and 2. That is, the plug 10 shown in Figs. 4 to 6 becomes the plug 3 of the spouted pouch 1 shown in Figs. 1 and 2 by being heat-sealed to the body film 4. For this reason, the material of the plug 10, the density of the resin constituting the plug 10, etc. can be made similar to those of the plug 3 of the spouted pouch 1.

[0026] The plug 10 includes a flow path 11, a spout portion 12, a welded portion 13, and a flange portion 14.

[0027] The flow path 11 extends in a first direction D1 and penetrates the spout 10 to allow the content contained in the containing area 6 of the spouted pouch 1 to flow. In other words, the flow path 11 is a hole defined by the inner circumferential surfaces of the pouring portion 12, the welded portion 13, and the flange portion 14, and is a through hole that penetrates the spout 10 in the first direction D1.

[0028] The spouting portion 12 is disposed outside the pouch body 2 of the spouted pouch 1, and is a portion for spouting the contents accommodated in the accommodation area 6 of the spouted pouch 1. The spouting portion 12 extends in a first direction D1, and forms a part of the flow path 11. The spouting portion 12 is formed in a cylindrical shape. The flow path 11 is formed on the inner peripheral surface of the spouting portion 12, and a screw portion 12a for detachably attaching a cap (not shown) is formed on the outer peripheral surface of the spouting portion 12. The cap is a member that closes the flow path 11 in an openable and closable manner.

[0029] The welded portion 13 is a portion that is welded to the body film 4. In other words, the welded portion 13 is disposed between the first body film 4A and the second body film 4B, and is a portion that is welded to the first body film 4A and the second body film 4B. The welded portion 13 extends in the first direction D1 and forms another part of the flow path 11.

[0030] The flange portion 14 is a flange-shaped portion located between the pouring portion 12 and the welding portion 13. The flange portion 14 is disposed on the outside of the pouch body 2 of the spouted pouch 1 and extends in a direction perpendicular to the first direction D1. The flange portion 14 is used, for example, to position the welding portion 13 relative to the body film 4. Note that, although only one flange portion 14 is provided in this embodiment, a plurality of flange portions 14 may be provided in the first direction D1.

[0031] The welded portion 13 has a shape in which the thickness in a third direction D3 perpendicular to the first direction D1 and the second direction D2 becomes thinner from the center in the second direction D2 perpendicular to the first direction D1 toward the end of the second direction D2. That is, the welded portion 13 has a cross section perpendicular to the first direction D1 that is substantially rhombic, and is longer in the second direction D2 than in the third direction D3. The outer surface of the welded portion 13 extends in a curved shape, for example, from the center in the second direction D2 toward the end of the second direction D2.

[0032] The welded portion 13 has a first side wall portion 16A welded to the first body film 4A and a second side wall portion 16B welded to the second body film 4B. The first side wall portion 16A and the second side wall portion 16B are positioned to face each other in the third direction D3, and are connected to each other at both ends in the second direction D2 so as to form an acute angle. Note that the first side wall portion 16A and the second side wall portion 16B have the same shape, structure, etc., and therefore, hereinafter, the first side wall portion 16A and the second side wall portion 16B will be collectively described as the side wall portion 16 unless otherwise specified.

[0033] The side wall portion 16 of the weld portion 13 has a base portion 17 and a plurality of ribs 19 .

[0034] The base 17 forms the main body of the side wall 16 and is the portion to be welded to the trunk film 4. The base 17 has a flat surface. The surface of the base 17 is substantially the same as that of the side wall 16. In other words, the base 17 has a shape in which the thickness in the third direction D3 decreases from the center in the second direction D2 toward the end in the second direction D2. The base 17 of the first side wall 16A and the base 17 of the second side wall 16B are positioned to face each other in the second direction D2 and are connected to each other at both ends in the third direction D3 at acute angles.

[0035] The multiple ribs 19 are portions that protrude from the base 17. The multiple ribs 19 are arranged in a first direction D1. Each of the multiple ribs 19 extends in a direction perpendicular to the first direction D1 on the surface of the base 17. Each of the multiple ribs 19 extends from an end of one side of the base 17 to an end of the other side in the second direction D2. The number of the multiple ribs 19 is not particularly limited, but in this embodiment, three ribs 19 are formed on each of the first side wall portion 16A and the second side wall portion 16B.

[0036] When manufacturing a spouted pouch 1 using the spout 10 configured in this manner, first, a pouch intermediate (not shown) is prepared in which the first body film 4A and the second body film 4B are not heat-sealed to each other at the upper edge portions in the pouch body 2. Next, a preheating step is performed. In the preheating step, a heated seal bar (not shown) is pressed against the welded portion 13 to preheat the welded portion 13. Note that the rib 19 becomes a flat surface along the surface of the base portion 17 by being crushed by the seal bar in the preheating step or the next heat sealing. Next, the welded portion 13 of the spout 10 is disposed between the upper edge portions of the first body film 4A and the second body film 4B. Next, a heat sealing step is performed. In the heat sealing step, a heated seal bar is pressed against the welded portion 13 from above the first body film 4A and the second body film 4B. Then, the sealant layer 8 of the first body film 4A and the second body film 4B melts, and the welded portion 13 of the spout 10 melts, and the sealant layer 8 of the first body film 4A and the second body film 4B is welded to the welded portion 13 of the spout 10. As a result, the first body film 4A and the second body film 4B are welded to the welded portion 13. The heat sealing process can be performed multiple times, for example, twice. The preheating process is not necessarily performed, but it is preferable to perform the preheating process from the viewpoint of appropriately melting the welded portion 13. If the preheating process is not performed, the melting of the welded portion 13 in the preheating process occurs in the heat sealing process. Next, a cooling process is performed. In the cooling process, the first body film 4A, the second body film 4B, and the welded portion 13 are cooled. As a result, the first body film 4A and the second body film 4B are completely welded to the welded portion 13, and the above-mentioned spout-equipped pouch 1 is manufactured.

[0037] In the heat sealing process, when the seal bar is pressed against the welded portion 13 from above the first and second trunk films 4A and 4B, the first and second trunk films 4A and 4B may be overheated. In such a case, since polyethylene has a relatively low melting point and a high thermal shrinkage rate, the first and second trunk films 4A and 4B undergo a large thermal shrinkage while melting. At this time, the welded portion 13 deforms to try to follow the thermal shrinkage of the first and second trunk films 4A and 4B. However, if the welded portion 13 is not easily deformed, the deformation of the welded portion 13 cannot follow the thermal shrinkage of the first and second trunk films 4A and 4B, and holes may be formed in the first and second trunk films 4A and 4B near the welded portion 13.

[0038] Therefore, in this embodiment, the welded portion 13 is made to be easily deformed so as to follow the thermal contraction of the first cylinder film 4A and the second cylinder film 4B. That is, when the indenter 52 (see FIG. 9) is pressed 4.5 mm into the welded portion 13 in the third direction D3, the load F [N] of the indenter 52 with respect to the pressing amount X [mm] of the indenter 52 in a predetermined region exceeding the yield point of the welded portion 13 is expressed as the contact area A [mm 2 ] divided by (F / A) slope S [N / mm 3 ] is 1.70N / mm 3 In other words, the slope S is the slope of a graph with the load F divided by the contact area A (F / A) on the vertical axis and the amount of push-in X on the horizontal axis, and the slope of this graph is 1.70N / mm 3 The slope S is also a value obtained by dividing a change Δ(F / A) in a value (F / A) obtained by dividing a load F by a contact area A in a predetermined region beyond the yield point of the welded portion 13 when the indenter 52 is pressed 4.5 mm into the welded portion 13 in the third direction D3, by a change ΔX in the pressing amount X. The load F is the force applied to the indenter 52 to press the indenter 52 into the welded portion 13. The pressing amount X is the pressing amount of the indenter 52 into the welded portion 13. In this case, the slope S is 1.50 N / mm 3 It may be less than 1.45N / mm 3The lower limit of the gradient S in the predetermined region exceeding the yield point of the welded portion 13 is not particularly limited, but may be, for example, 1.0 N / mm 3 It can be more than that.

[0039] Next, a method for determining the slope S will be described. First, an indentation test is performed. FIG. 7 is a front view showing a state in which an indentation test is being performed. As shown in FIG. 7, in the indentation test, a mounting table 50 is prepared for mounting the welded portion 13. Mounting table 50 is formed with a mounting surface 51 shaped to fit the outer surface of welded portion 13. Then, welded portion 13 is mounted on mounting surface 51 of mounting table 50.

[0040] Next, the indenter 52 is pressed into the welded portion 13 using a force gauge EMX series EMX-500N manufactured by Imada Co., Ltd., and the load F of the indenter 52 and the indentation amount X of the indenter 52 are measured. The indenter 52 is pressed into the welded portion 13 at a pressing speed of 20 mm / min and a maximum pressing amount of 4.5 mm by pressing the indenter 52 in the third direction D3 into the center of the welded portion 13 in the second direction D2. The pressing surface 53 of the indenter 52 is a circle with a diameter of 10 mm. As the indenter 52, for example, a metal disc-shaped indenter with a diameter of 10 mm is used. An example of the measurement results of the indentation test is shown in FIG. 8. In FIG. 8, the vertical axis represents the value (F / A) obtained by dividing the load F by the contact area A, and the horizontal axis represents the indentation amount X.

[0041] Here, the welded portion 13 is made of high-density polyethylene and has a complex shape in which the thickness in the third direction D3 decreases from the center in the second direction D2 toward the end in the second direction D2. Therefore, when the indenter 52 is pressed into the welded portion 13 in the third direction D3, the contact area between the welded portion 13 and the indenter 52 changes (increases). Therefore, as shown in FIG. 9, the area of ​​the surface where the welded portion 13 and the indenter 52 finally come into contact when the indenter 52 is pressed 5.4 mm into the welded portion 13 in the third direction D3 is defined as the contact area A between the welded portion 13 and the indenter 52. The contact area A is also the maximum contact area between the welded portion 13 and the indenter 52 when the indenter 52 is pressed 5.4 mm into the welded portion 13 in the third direction D3.

[0042] FIG. 9 is a diagram for explaining the contact area, and shows a state in which the indenter 52 is pressed 5.4 mm into the welded portion 13 in the third direction D3. In FIG. 9, the area of ​​the region hatched with diagonal lines is the contact area A. Here, when the indenter 52 is pressed into the welded portion 13, the indenter 52 first contacts the rib 19. When the indenter 52 is further pressed into the welded portion 13, the rib 19 is crushed by the indenter 52 and becomes a flat surface along the surface of the base 17. As a result, the indenter 52 contacts both the base 17 and the rib 19. Therefore, the contact area A is the area of ​​the region corresponding to the base 17 and the rib 19 in the projection plane of the pressing surface 53 of the indenter 52 projected onto the welded portion 13 in the third direction D3.

[0043] As shown in Fig. 8, in the elastic region before the yield point is reached, when indenter 52 is pressed into welded portion 13, slope S, which is the slope of the line shown in Fig. 8, changes. On the other hand, in the plastic region beyond the yield point, slope S, which is the slope of the line shown in Fig. 8, is unlikely to change even if indenter 52 is pressed into welded portion 13.

[0044] Therefore, the slope S is calculated in a predetermined region beyond the yield point of the welded portion 13, which is the plastic region. In this embodiment, the calculated slope S is 1.70 N / mm 3 Below, 1.50N / mm 3 Less than or equal to 1.45N / mm 3 The predetermined region is not particularly limited, but may be, for example, a region where the slope S becomes constant beyond the yield point of the welded portion 13, or a section from when the slope S becomes constant beyond the yield point until the amount of depression X increases by 0.5 mm may be the predetermined region. In this case, in FIG. 8, the section where the amount of depression X is 1.25 mm to 1.75 mm is the predetermined region. Then, the slope S is calculated in this predetermined region, and when the calculated slope S is 1.70 N / mm 3 Below, 1.50N / mm 3 Less than or equal to 1.45N / mm 3 The details are as follows.

[0045] As described above, in the plug 10 according to this embodiment, the welded portion 13 has a complex shape in which the thickness in the third direction D3 decreases from the center in the second direction D2 toward the end in the second direction D2, so that when the seal bar is pressed against the welded portion 13 from above the first body film 4A and the second body film 4B, the first body film 4A and the second body film 4B are likely to be locally overheated. However, when the slope S in a predetermined region beyond the yield point of the welded portion is 1.70 N / mm 3 Below, 1.50N / mm 3 Less than or equal to 1.45N / mm 3 Therefore, even if the first body film 4A and the second body film 4B are overheated as a result of the seal bar being pressed against the welded portion 13 from above the first body film 4A and the second body film 4B, the welded portion 13 deforms to follow the thermal shrinkage of the first body film 4A and the second body film 4B, thereby preventing holes from being formed in the first body film 4A and the second body film 4B near the plug 10.

[0046] In addition, in this plug 10, the welded portion 13 has a rib 19 protruding from the base 17, so that when the seal bar is pressed against the welded portion 13 from above the first body film 4A and the second body film 4B, the contact area between the welded portion 13 and the first body film 4A and the second body film 4B is small, and the first body film 4A and the second body film 4B are easily locally overheated. However, when the above-mentioned gradient S is 1.70 N / mm 3 Below, 1.50N / mm 3 Less than or equal to 1.45N / mm 3 As a result, the welded portion 13 deforms to follow the thermal shrinkage of the first body film 4A and the second body film 4B, thereby preventing holes from being formed in the first body film 4A and the second body film 4B near the spout 10.

[0047] In the spouted pouch 1 according to this embodiment, the spout 10 is welded to the first body film 4A and the second body film 4B, so that even if the first body film 4A and the second body film 4B are locally overheated when a seal bar is pressed against the welded portion 13 of the spout 10 from above the first body film 4A and the second body film 4B during the manufacture of the spouted pouch 1, the welded portion 13 deforms to follow the thermal shrinkage of the first body film 4A and the second body film 4B, thereby preventing holes from being formed in the first body film 4A and the second body film 4B near the spout 10. This makes it possible to prevent holes from being formed in the first body film 4A and the second body film 4B.

[0048] Although an embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and may be modified or applied to other things without departing from the gist of the claims.

[0049] For example, in the above embodiment, the shape of the plug is specifically described, but the shape of the plug is not particularly limited and can be appropriately changed, such as the modified plugs shown in Figures 10 to 12 and other modified plugs shown in Figures 14 to 16. Also, in the above embodiment, the welded part of the plug has a rib protruding from the base, but it may have no rib from the base, a groove recessed from the base, or a hole formed in the welded part, such as the modified plugs shown in Figures 10 to 12 and other modified plugs shown in Figures 14 to 16.

[0050] (Modified plug) FIG. 10 is a front view showing a modified plug. FIG. 11 is a side view showing a modified plug. FIG. 12 is a bottom view showing a modified plug. The modified plug 110 shown in FIGS. 10 to 12 is basically the same as the plug 10 of the above embodiment, but is partially different in shape from the plug 10 of the above embodiment. The plug 110 includes the same flow path 11 as the plug 10, a pouring portion 112 corresponding to the pouring portion 12, a welded portion 113 corresponding to the welded portion 13, and a flange portion 114 corresponding to the flange portion 14. The pouring portion 112 and the flange portion 114 have different shapes from the pouring portion 12 and the flange portion 14, but since this is not directly related to the features of the present invention, a description thereof will be omitted.

[0051] The welded portion 113 has a shape in which the thickness in the third direction D3 decreases from the center in the second direction D2 toward the end in the second direction D2. The welded portion 113 has a first side wall portion 116A corresponding to the first side wall portion 16A, and a second side wall portion 116B corresponding to the second side wall portion 16B. The first side wall portion 116A and the second side wall portion 116B have the same shape, structure, etc., and therefore, hereinafter, the first side wall portion 116A and the second side wall portion 116B will be collectively described as the side wall portion 116 unless otherwise specifically described separately.

[0052] The sidewall 116 of the weld 113 has a base 117 and a plurality of grooves 118 .

[0053] The base 117 forms the main body of the side wall 116 and is the portion to be welded to the body film 4 .

[0054] The grooves 118 are recessed from the base 117. The grooves 118 are arranged in the first direction D1. Each of the grooves 118 extends in a direction perpendicular to the first direction D1 on the surface of the base 117. Each of the grooves 118 extends from the vicinity of the tip of one side of the base 117 in the second direction D2 to the vicinity of the tip of the other side, and is not formed at both ends of the base 117 in the second direction D2. The number of grooves 118 arranged in the first direction D1 is not particularly limited, but in this embodiment, three grooves 118 are arranged (formed) in the first direction D1 on each of the first side wall portion 116A and the second side wall portion 116B.

[0055] The inclination S of the plug 110 thus configured can be obtained in the same manner as the inclination S of the plug 10 described above. However, since the shape of the welded portion 113 is different from that of the welded portion 13, the contact area A between the welded portion 113 and the indenter 52 is as shown in FIG. 13. FIG. 13 is a diagram for explaining the contact area in the plug of the modified example, and shows a state in which the indenter 52 is pressed 5.4 mm into the welded portion 113 in the third direction D3. In FIG. 13, the area of ​​the region hatched with oblique lines is the contact area A. Here, when the indenter 52 is pressed into the welded portion 113, the indenter 52 contacts the base 117, but the groove 118 sinks together with the base 117, so the indenter 52 does not contact the groove 118. Therefore, the contact area A is the area of ​​the projection surface of the pressing surface 53 of the indenter 52 projected onto the welded portion 113 in the third direction D3, excluding the area corresponding to the groove 118.

[0056] As explained above, in the modified plug 110, the welded portion 113 has a groove 118 recessed from the base 117, so that when the seal bar is pressed against the welded portion 113 from above the first body film 4A and the second body film 4B, the contact area between the welded portion 113 and the first body film 4A and the second body film 4B is small, and the first body film 4A and the second body film 4B are easily locally overheated. However, when the above-mentioned slope S is 1.70 N / mm 3 Below, 1.50N / mm 3 Less than or equal to 1.45N / mm 3As described below, the welded portion 113 deforms to follow the thermal shrinkage of the first body film 4A and the second body film 4B, thereby preventing holes from being formed in the first body film 4A and the second body film 4B near the spout 110.

[0057] (Other modified plugs) FIG. 14 is a front view showing a plug of another modified example. FIG. 15 is a side view showing a plug of another modified example. FIG. 16 is a bottom view showing a plug of another modified example. A plug 210 of another modified example shown in FIG. 14 to FIG. 16 is basically the same as the plug 110 of the modified example, but is partially different in shape from the plug 110 of the modified example. The plug 210 includes the same flow path 11 as the plug 110, a spouting portion 212 corresponding to the spouting portion 112, a welded portion 213 corresponding to the welded portion 113, and a flange portion 214 corresponding to the flange portion 114. The spouting portion 212 and the flange portion 214 are different in shape from the spouting portion 112 and the flange portion 114, but the description thereof will be omitted since it is not directly related to the features of the present invention.

[0058] The welded portion 213 has a shape in which the thickness in the third direction D3 decreases from the center in the second direction D2 toward the end in the second direction D2. The welded portion 213 has a first side wall portion 216A corresponding to the first side wall portion 116A, and a second side wall portion 216B corresponding to the second side wall portion 116B. The first side wall portion 216A and the second side wall portion 216B have the same shape, structure, etc., and therefore, hereinafter, the first side wall portion 216A and the second side wall portion 216B will be collectively described as the side wall portion 216 unless otherwise specifically described separately.

[0059] The side wall portion 216 of the welded portion 213 has the same base portion 117 as the plug 110 , a plurality of grooves 118 as the plug 110 , and a plurality of support portions 221 .

[0060] The plurality of support parts 221 are formed in the groove 118 and are parts that support the base part 117. The base part 117 is thinned by the formation of the plurality of grooves 118, and has a shape that is easily buckled as it is. For this reason, the support parts 221 support the base part 117 from the groove 118 in order to suppress the buckling of the base part 117. Each of the plurality of support parts 221 extends in the first direction D1 from the flange part 214 toward the opposite side to the pouring part 212, and is formed in the entire area in the first direction D1 of the groove 118 located closest to the pouring part 112 side, and in a part in the first direction D1 of the groove 118 adjacent to the groove 118. The number of the plurality of support parts 221 is not particularly limited, but in this embodiment, two support parts 221 are formed on each of the first side wall part 16A and the second side wall part 16B.

[0061] The inclination S of the plug 210 thus configured can be obtained in the same manner as the inclination S of the plug 10 described above. However, since the shape of the welded portion 213 is different from that of the welded portion 13, the contact area A between the welded portion 213 and the indenter 52 is as shown in FIG. 17. FIG. 17 is a diagram for explaining the contact area in a plug of another modification, and shows a state in which the indenter 52 is pressed 5.4 mm into the welded portion 213 in the third direction D3. In FIG. 17, the area of ​​the region hatched with oblique lines is the contact area A. Here, when the indenter 52 is pressed into the welded portion 213, the indenter 52 comes into contact with the base portion 117, but the groove 118 and the support portion 221 sink together with the base portion 117, so that the indenter 52 does not come into contact with the groove 118 and the support portion 221. Therefore, the contact area A is the area of ​​the projection plane of the pressing surface 53 of the pressing tool 52 projected onto the welded portion 213 in the third direction D3, excluding the regions corresponding to the groove 118 and the support portion 221. EXAMPLES

[0062] Next, examples of the present invention will be described, but the present invention is not limited to the following examples.

[0063] (Preparation of Laminate) The following materials were used to make the laminate: Base layer: Unstretched HDPE film (thickness: 35 μm, density: 0.948 g / cm 3 , melting point: 135℃) Adhesive layer: Urethane adhesive First sealing layer: Low temperature sealable LLDPE (density: 0.916g / cm 3 , MFR: 4.0g / 10min, Melting point: 102℃) Second sealing layer: Anti-adhesion VLDPE (density: 0.913g / cm 3 , MFR: 10.0g / 10min, Melting point: 104℃)

[0064] A first seal layer (thickness: 80 μm) was provided on the surface of the support film. A second seal layer (thickness: 20 μm) was provided on the surface of this first seal layer to obtain a sealant layer with a two-layer structure. This sealant layer and the base layer were bonded together via an adhesive layer (thickness: 1 to 2 μm) to obtain a laminate. After the base layer and the sealant layer were bonded together, the support film was peeled off.

[0065] (Making the plug) The plugs of Examples 1 and 2 and Comparative Example 1 were made of high density polyethylene (HDPE). Each of the plugs of Examples 1 and 2 and Comparative Example 1 had a flow path extending in a first direction, a pouring portion extending in the first direction to form a part of the flow path, and a welded portion extending in the first direction to form another part of the flow path, and the welded portion had a shape in which the thickness in a third direction perpendicular to the first and second directions became thinner from a center in a second direction perpendicular to the first direction to an end in the second direction.

[0066] (Melt point measurement) The melting point of each plug was measured. In the measurement of the melting point, the differential scanning calorimetry of each plug was measured twice using a differential scanning calorimeter (DSC8000, manufactured by PerkinElmer). Since the thermal history at the time of the production of the plug may remain in the first differential scanning calorimetry, the temperature at the apex of the endothermic peak of the DSC curve obtained in the second differential scanning calorimetry was taken as the melting point of each plug. The melting point of the plug of Example 1 was 127.63°C. The melting point of the plug of Example 2 was 127.27°C. The melting point of the plug of Comparative Example 1 was 129.69°C.

[0067] (Indentation test) A push-in test was performed on each plug. In the push-in test, a mounting table was prepared for mounting the welded portion of each plug. The mounting table had a mounting surface formed in a shape that conformed to the outer surface of the welded portion of each plug. Then, after the welded portion of each plug was mounted on the mounting surface of the mounting table, a metal disk-shaped indenter with a diameter of 10 mm was pressed into the welded portion of each plug using a force gauge EMX series EMX-500N manufactured by IMADA Co., Ltd., and the load F of the indenter and the indenter push-in amount X at that time were measured. The indenter was pressed into the welded portion by pressing the indenter in the third direction into the center of the welded portion in the second direction under the conditions of a push-in speed of 20 mm / min and a maximum push-in amount of 4.5 mm. The indenter push-in surface was a circle with a diameter of 10 mm.

[0068] (Calculation of slope S) FIG. 18 is a graph plotting the measurement results of the indentation test in Examples 1 and 2 and Comparative Example 1. As shown in FIG. 18, the measurement results of the indentation test were plotted on a graph with the indenter load F divided by the contact area A between the welded portion and the indenter (F / A) on the vertical axis and the indenter indentation amount X on the horizontal axis. The contact area A was defined as the area of ​​the surface where the welded portion and the indenter finally come into contact when the indenter is pressed into the welded portion by 5.4 mm in the third direction. In the graph plotting the measurement results of the indentation test, the section from when the slope S becomes constant after the yield point of the welded portion is exceeded until the indentation amount X increases by 0.5 mm was defined as the predetermined region. This predetermined region was the section where the indenter indentation amount X was 1.25 mm to 1.75 mm. Then, for each plug, the slope S of the value (F / A) obtained by dividing the load F of the indenter 52 by the contact area A between the welded portion 13 and the indenter 52 relative to the amount of depression X of the indenter 52 in this specified region was calculated. The slope S was determined as the value obtained by dividing the amount of change Δ(F / A) in the value (F / A) obtained by dividing the load F by the contact area A in this specified region by the amount of change ΔX in the amount of depression X. The calculation results are shown in Table 1.

[0069] [Table 1]

[0070] (Sample Preparation) A pair of laminates was welded to each plug by heat sealing using a welding machine manufactured by Totani Giken Kogyo Co., Ltd., to obtain samples of Examples 1 to 5 and Comparative Example 1. In this heat sealing, the welded part was preheated under the conditions of temperature: 150°C, time: 0.9 sec, and pressure: 0.6 MPa, and then stored in a thermostatic chamber under the conditions of temperature: 100°C, time: 10 min. Thereafter, the welded part was placed between the pair of laminates, and primary sealing was performed under the conditions of temperature: 135°C, time: 0.9 sec, and pressure: 0.6 MPa, and secondary sealing was performed under the conditions of temperature: 130°C, time: 0.9 sec, and pressure: 0.6 MPa. Thereafter, cooling was performed under the conditions of temperature: room temperature, time: 1.5 seconds.

[0071] (Heat seal evaluation) Heat seal evaluation was performed on the samples of Examples 1 to 5 and Comparative Example 1. In the heat seal evaluation, a case where a hole was observed in the laminate near the plug was evaluated as B, and a case where no hole was observed in the laminate near the plug was evaluated as A. The results are shown in Table 1.

[0072] (Consideration) As shown in Table 1, the appearance evaluation showed that the slope S was 1.70 N / mm 3 In Comparative Example 1, a hole was observed in the laminate near the spout, whereas the slope S was 1.70 N / mm 3 In the following Examples 1 and 2, no holes were observed in the laminate near the spout. From these results, it can be seen that the slope S was 1.70 N / mm 3 It is presumed that if the thickness is below this, it is possible to prevent holes from being formed in the film near the plug. [Explanation of symbols]

[0073] 1 ... pouch with spout, 2 ... pouch body, 3 ... spout, 4 ... body film, 4A ... first body film, 4B ... second body film, 5 ... fold-in film, 6 ... storage area, 7 ... base layer, 8 ... sealant layer, 10 ... spout, 11 ... flow path, 12 ... pouring portion, 12a ... screw portion, 13 ... welding portion, 14 ... flange portion, 16 ... side wall portion, 16A ... first side wall portion, 16B ... second side wall portion, 17 ... base portion, 19 ... rib, 31 ... flow path, 32 ... pouring portion, 33 ... welding portion, 34 ... flange portion, 5 0...support base, 51...support surface, 52...indenter, 53...pressing surface, 110...stopper, 112...pouring portion, 113...welded portion, 114...flange portion, 116...side wall portion, 116A...first side wall portion, 116B...second side wall portion, 117...base, 118...groove, 210...stopper, 212...pouring portion, 213...welded portion, 214...flange portion, 216...side wall portion, 216A...first side wall portion, 216B...second side wall portion, 221...support portion, D1...first direction, D2...second direction, D3...third direction.

Claims

1. A high density polyethylene stopper for use in a pouch, A flow path extending in a first direction; A pouring portion extending in the first direction and forming a part of the flow path; a welded portion extending in the first direction and forming another part of the flow path, the welded portion has a shape in which a thickness in a third direction perpendicular to the first direction and the second direction becomes thinner from a center portion in a second direction perpendicular to the first direction toward an end portion in the second direction, When the indenter is pressed 4.5 mm into the welded portion in the third direction, the slope of the value obtained by dividing the load of the indenter by the contact area between the welded portion and the indenter with respect to the amount of pressing of the indenter in a predetermined region exceeding the yield point of the welded portion is 1.70 N / mm ３ Below is the Mouth plug.

2. The welding portion has a base and a rib protruding from the base. The plug according to claim 1.

3. The welding portion has a base and a groove recessed from the base. The plug according to claim 1.

4. A pouch body having a pair of films; and the plug according to any one of claims 1 to 3, which is disposed between a pair of films and welded to the pair of films; Each of the pair of films has a sealant layer containing polyethylene on its innermost surface. Pouch with stopper.

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