Mouthed packaging bag and method for manufacturing mouthed packaging bag

Abstract

A packaging bag (1) with a mouth is provided with: a housing part (10) comprising a laminated film (16) having a base material (17) and a sealing layer (18) that are made of the same material; and a nozzle (20) having a pouring tube (21) and a base (22) provided on one end side of the pouring tube (21), the nozzle (20) being attached to the upper end portion (11) of the accommodating portion (10). At the upper end part (11) of the accommodating part (10), the sealing layers (18) are welded to the base (22) of the nozzle (20), and the sealing layers (18) are welded to each other beside the base (22). In the packaging bag (1) with the nozzle, the width (D1) of a first welding area (R1) where the sealing layers (18) are welded to the base (22) is shorter than the width (D2) of a second welding area (R2) where the sealing layers (18) are welded to each other, and a step (S) is formed between the first welding area (R1) and the second welding area (R2).

Description

Technical Field

[0001] The present invention relates to a packaging bag with a spout and a method for manufacturing the packaging bag with a spout. Background Art

[0002] Spouted packaging bags are known that can hold specific contents (e.g., liquid detergent or shampoo) and dispense the contents as needed. These packaging bags are made of a multi-material laminate film comprising a sealant layer made of, for example, polyolefin and a base material made of a material with a higher melting point than the sealant layer (e.g., polyester). From an environmental perspective, efforts to make packaging materials mono-material have been underway in recent years, and research is underway to use laminate films primarily composed of polypropylene, etc., as packaging materials, instead of multi-material laminate films (e.g., see Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2020-157517

[0006] Patent Document 2: Japanese Patent Application Laid-Open No. 2017-065747

[0007] Patent Document 3: Japanese Patent Application No. 2010-511634

[0008] Patent Document 4: Japanese Patent Application Laid-Open No. 2013-177531 Summary of the Invention

[0009] Problems to be solved by the invention

[0010] When spouted packaging bags are made from a laminated film with a single material structure, the melting point of the material constituting the sealing layer is the same as that of the base material. Therefore, compared to spouted packaging bags made from a laminated film with a multi-material structure, the temperature at which the sealing layer is welded to the spout must be lower. However, lowering the welding temperature can lead to insufficient welding of the sealing layer and the spout, and the seal strength at the portion where the sealing layer is welded to the spout may decrease. Therefore, when spouted packaging bags are made from a laminated film with a single material structure, the pressure resistance of the bag when filled with contents may decrease.

[0011] An object of the present invention is to provide a spouted packaging bag having improved pressure resistance even when a laminated film having a single material structure is used, and a method for producing the spouted packaging bag.

[0012] Solutions for solving problems

[0013] [1] One aspect of the present invention relates to a packaging bag with a spout. The packaging bag with a spout comprises: a container portion formed of a laminate film having a base material and a sealing layer formed of the same material; and a spout having a pouring tube extending in a first direction and a base provided at one end of the pouring tube, the spout being mounted on the edge of the container portion. At the edge of the container portion, the sealing layer is welded to the base of the spout, and the sealing layers are welded to each other beside the base. In the packaging bag with a spout, the width of a first welded region in which the sealing layer is welded to the base along the first direction is shorter than the width of a second welded region in which the sealing layers are welded to each other along the first direction, and a step is formed between the first welded region and the second welded region.

[0014] In this spouted packaging bag, a step is provided between the first welded area where the sealing layer is welded to the base of the spout and the second welded area where the sealing layers are welded to each other. By providing such a step, when the portion of the laminated film with a single material structure located at the lower portion of the spout (the step) is heated (during manufacturing), the film portion softens and deforms inwardly by shrinking (see Figure 5 According to the research of the present inventors, due to the concave (contracted) structure of the laminated film, when the contents are placed in the packaging bag, the pressure of the contents that should be applied to the portion where the sealing layer is welded to the mouth (the end of the mouth) becomes difficult to apply, and the stress is dispersed to the portion other than this portion, and the pressure is directed toward the area where the sealing layers are welded to each other located next to the mouth (see Figure 7 (b)). The sealing strength of the second welded region between the sealing layers is higher than the sealing strength of the first welded region where the sealing layer is welded to the spout (base). Thus, this spouted packaging bag can improve pressure resistance even when using a laminated film made of a single material.

[0015] [2] In the spouted packaging bag of [1], the dimension of the step along the first direction is preferably 1.5 mm or greater. In this case, the portion of the laminated film located below the spout (the step) can be more reliably deformed to contract inward, thereby distributing the pressure. Thus, according to this spouted packaging bag, even when using a laminated film having a single material structure, the compressive strength can be more reliably improved.

[0016] [3] In the spouted packaging bag of [1] or [2] above, the dimension of the step along the first direction is preferably 5 mm or less. The step portion between the first welded area where the sealing layer is welded to the base of the spout and the second welded area where the sealing layers are welded to each other constitutes a flow path when the contents contained in the container are poured out from the pouring tube of the spout. As described above, the portion of the laminated film corresponding to the step becomes a structure that contracts inward, and the flow path is narrowed. Therefore, in this spouted packaging bag, the length of the step is set to 5 mm or less. Thus, according to this spouted packaging bag, the contents contained in the packaging bag can be easily poured out.

[0017] [4] In the spouted packaging bag of any one of [1] to [3] above, the dimension of the step along the first direction may be 0.15 to 0.6 relative to the length of the base along the first direction. In this case, by making the dimension of the step 0.15 or more relative to the length of the base, as described above, the portion of the laminated film located at the lower portion of the spout (the step) is deformed inwardly contracting to achieve pressure dispersion, thereby more reliably improving the pressure resistance even when using a laminated film of a single material structure. In addition, by making the dimension of the step 0.6 or less relative to the length of the base, as described above, the flow path can be prevented from being excessively long, thereby making it easier to pour out the contents of the packaging bag.

[0018] [5] In the spouted packaging bag of any one of [1] to [4] above, the dimension of the step along the first direction may be 0.1 to 0.5 relative to the lateral width of the base along the second direction intersecting the first direction. In this case, by making the dimension of the step 0.1 or more relative to the lateral width of the base, as described above, the portion of the laminated film located at the lower portion of the spout (the step) is deformed inwardly contracting to achieve pressure dispersion, thereby more reliably improving the pressure resistance even when using a laminated film of a single material structure. In addition, by making the dimension of the step 0.5 or less relative to the lateral width of the base, as described above, the flow path can be prevented from being too long, thereby making it easier to pour out the contents of the packaging bag.

[0019] [6] In the spout packaging bag of any one of [1] to [5] above, it is preferred that the base material and the sealing layer are made of the same material, polyethylene resin or polypropylene resin. By using such a material, softening during welding is facilitated, and when the portion of the laminated film located at the lower portion (step) of the spout is heated, the portion of the film can be more reliably deformed so as to contract inward. This improves the compressive strength even when a laminated film having a single material structure is used.

[0020] [7] In the spout packaging bag of any one of [1] to [6] above, the same material constituting the base material and the sealing layer may be polyethylene resin, and the content of polyethylene resin in the entire laminated film may be 90% by mass or more. In this case, softening during welding is easily promoted, and when the portion of the laminated film located at the lower portion (step) of the spout is heated, the portion of the film can be more reliably deformed in a manner of shrinking inward. Thus, even when a laminated film having a single material structure is used, the compressive strength can be improved. In addition, in this case, recyclability can also be improved.

[0021] [8] In the spouted packaging bag of any one of [1] to [7] above, it is preferred that the receiving portion is formed such that the opposing sealing layers are recessed inwardly at a step between the first welded area and the second welded area. In this case, even when pressure is applied to the packaging bag after the contents are placed in the packaging bag, the pressure is less likely to be applied to the first area (end of the spout) where the sealing layers are welded to the spout, and the pressure is dispersed to the portion where the sealing layers are welded to each other. Thus, according to this spouted packaging bag, the pressure resistance can be improved even when a laminated film having a single material structure is used.

[0022] [9] Another aspect of the present invention relates to a method for manufacturing a spouted packaging bag. The method comprises the following steps: preparing a laminated film having a base material and a sealing layer made of the same material; preparing a spout having a pouring tube and a base provided on one end of the pouring tube; and welding the sealing layer of the laminated film to the base of the spout, and welding the sealing layers to each other beside the base. In the welding step, the sealing layers are welded to the base so that the width of a first welded region where the sealing layers are welded to the base is shorter than the width of a second welded region where the sealing layers are welded to each other, and a step is formed between the first welded region and the second welded region.

[0023] In this method for manufacturing a spouted packaging bag, during the welding process, the width of a first welded region where the sealing layer is welded to the base is shorter than the width of a second welded region where the sealing layers are welded to each other, and a step is formed between the first and second welded regions. By providing this step, when the portion of the laminated film with a single material structure located below the spout (the step) is heated, this portion of the film softens and deforms by shrinking inward. Because the film has such a concave (shrinking) structure, even when pressure is applied to the contents of the packaging bag, the pressure is less likely to be applied to the first welded region (the end of the spout) where the sealing layer is welded to the spout, and instead is directed toward the second welded region where the sealing layers are welded to each other. Thus, according to this method for manufacturing a spouted packaging bag, a packaging bag with improved pressure resistance can be obtained even when using a laminated film with a single material structure. Furthermore, the present inventors' research has revealed that, when attempting to manufacture spouted packaging bags without steps, as in conventional structures, using a laminated film with a single material structure, the manufacturing conditions (the range of sealing temperature conditions) required to achieve seal strength and compressive strength above specified values ​​become extremely narrow (see the comparative examples described below). Consequently, conventional manufacturing methods reduce productivity. However, the present manufacturing method broadens the range of manufacturing conditions required to achieve seal strength and compressive strength above specified values, thereby improving productivity and yield rates.

[0024]

[10] In the method for manufacturing a spouted packaging bag of [9], it is preferred that the width of the step is 1.5 mm to 5 mm. By making the width of the step 1.5 mm or more, the portion of the laminated film located at the lower portion of the spout (the step) can be more reliably deformed in a manner that contracts inward. Thus, according to the spouted packaging bag, the pressure resistance can be more reliably improved even when a laminated film having a single material structure is used. On the other hand, by making the width of the step 5 mm or less, as described above, the length of the narrow flow path can be limited, thereby making it easy to pour out the contents contained in the packaging bag.

[0025] Effects of the Invention

[0026] According to the present invention, a spouted packaging pouch having improved pressure resistance and a method for producing the spouted packaging pouch can be provided even when a laminated film having a single material structure is used. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a front view showing a spouted packaging bag according to one embodiment.

[0028] Figure 2 It means composition Figure 1 A cross-sectional view of a cross section of a laminated film of a spouted packaging bag is shown.

[0029] Figure 3 (a) is used for Figure 1 The front view of the mouth of the spouted packaging bag shown, Figure 3 (b) is a cross-sectional view of the nozzle viewed from below (base side).

[0030] Figure 4 It is an enlarged representation Figure 1 A front view of the vicinity of the welded portion of the spout of the spouted packaging bag shown.

[0031] Figure 5 Yes Figure 4 A cross-sectional view of a section near the welded portion of the nozzle shown.

[0032] Figure 6 (a) is an enlarged front view showing the vicinity of the welded portion of the spout of the spouted packaging bag of the comparative example. Figure 6 (b) is Figure 6 (a) is a cross-sectional view of .

[0033] Figure 7 (a) is a diagram for explaining the pressure applied when the spouted packaging bag of the comparative example is filled with content (liquid). Figure 7 (b) is a diagram for explaining pressure applied when the spouted packaging bag of the present embodiment is filled with content (liquid).

[0034] Figure 8 This is a diagram showing an example of a test piece used in a seal strength test. DETAILED DESCRIPTION

[0035] The following describes in detail one embodiment of a spouted packaging bag according to the present invention with reference to the accompanying drawings. In the following description, identical elements or elements having identical functions are sometimes denoted by identical reference numerals, and duplicate descriptions are omitted. It should be noted that the present invention is not limited to the following embodiment.

[0036] Figure 1 FIG. 1 is a top view of a spouted packaging bag according to an embodiment of the present invention. Figure 1 As shown, the spouted packaging bag 1 comprises a container 10 made of a laminated film of a single material structure and a spout 20 mounted on an upper end 11 (edge) of the container 10. The container 10 constitutes the bag portion of the spouted packaging bag 1 and is formed by a sealing layer 18 (see FIG. 1 ) formed by a laminated film 16. Figure 2 ) are welded (sealed) together to form an upper end portion 11, a lower end portion 12, and side portions 13 and 14, which enclose a container area 15 for the contents. For example, liquid detergent, shampoo, etc. are stored in the container area 15 of the container portion 10. The contents of the container portion 10 can be poured out from the spout 20. It should be noted that such a spouted packaging bag can be a so-called stand-up pouch.

[0037] Figure 2 1 is a diagram showing a cross section of a laminated film constituting the container portion 10 of the spouted packaging bag 1. Figure 2 As shown, the laminated film 16 constituting the housing portion 10 is a laminated film of a single material structure, having a base material 17 and a sealing layer 18 made of the same material. As the same material constituting the base material 17 and the sealing layer 18, for example, polyethylene resin or polypropylene resin can be used. In addition, in order to form the housing portion 10 from the laminated film 16, a plurality of such laminated films 16 are prepared, and the upper end portion 11, the lower end portion 12, and the side portions 13 and 14 are welded so that the respective sealing layers 18 are on the inner side, and the laminated film 16 is formed. Figure 1 It should be noted that the "same material" mentioned here does not only refer to completely identical materials, but also includes materials with the same main constituent materials.

[0038] [Base material]

[0039] The substrate 17 is made of, for example, polyethylene resin or polypropylene resin. Since the substrate 17 is an unstretched polyethylene resin film, there is almost no orientation of the resin, and it is easy to stretch and not easy to break under external stress such as stretching and shearing. Since the substrate 17 is a stretched polyethylene resin film, it has excellent puncture resistance. The thickness of the substrate 17 is, for example, 5 to 800 μm, or 5 to 500 μm or 10 to 50 μm. The substrate 17 may have a melting point that is 20°C higher than that of the sealing layer 18, and preferably has a melting point that is 25°C higher than that of the sealing layer 18. Due to the difference in melting points between the two, the melting of the substrate 17 can be suppressed during the heat sealing process. The difference in the sealing start temperature between the substrate 17 and the sealing layer 18 is preferably 25°C or more, more preferably 30°C or more. The sealing start temperature refers to the temperature at which the sealing strength is manifested. The melting point of the polyethylene resin can be measured using a differential scanning calorimeter (DSC: Differential Scanning Calorimeter).

[0040] The melting point of the substrate 17 is, for example, in the range of 100 to 170°C, preferably 120°C or higher, and more preferably 125°C or higher. Examples of polyethylene constituting the substrate 17 include high-density polyethylene (HDPE) and medium-density polyethylene (MDPE). Among them, HDPE and MDPE having a density of 0.925 g / cm 3 Polyethylene with a density of 0.93 to 0.98 g / cm is particularly preferred. 3 range of high density polyethylene.

[0041] The polyethylene resin constituting substrate 17 is not limited to petroleum-derived polyethylene resins; some or all of it may be a bio-derived resin material (e.g., biomass-derived polyethylene using biomass-derived ethylene as a raw material). Methods for producing biomass-derived polyethylene are disclosed, for example, in Japanese Patent Application Publication No. 2010-511634. Substrate 17 may comprise commercially available biomass polyethylene (e.g., Green PE manufactured by Braskem) or mechanically recycled polyethylene derived from used polyethylene products or resin (so-called burr) generated during the manufacturing process of polyethylene products.

[0042] Substrate 17 may also contain components other than polyethylene resin. Examples of such components include polyamide, polyethylene terephthalate, polypropylene, polyvinyl alcohol, and biodegradable resin materials (e.g., polylactic acid, polycaprolactone, polyhydroxyalkanoate, polyglycolic acid, modified polyvinyl alcohol, casein, and modified starch). Substrate 17 may also contain additives such as antistatic agents, UV absorbers, plasticizers, lubricants, and colorants. The amount of components other than polyethylene resin in substrate 17 is preferably 15% by mass or less, and more preferably 10% by mass or less, based on the total amount of substrate 17.

[0043] [Sealing layer]

[0044] Like the substrate 17, the sealant layer 18 is made of a polyethylene resin film. That is, the sealant layer 18 is made of the same material as the substrate 17. It should be noted that the term "same material" here refers to the fact that the main resin (e.g., polyethylene resin) is the same, and this also includes the case where components other than the main resin are different. The thickness of the sealant layer 18 is, for example, 40 to 150 μm, or 20 to 250 μm. The polyethylene resin film that constitutes the sealant layer 18 is a film that is easily tearable in the machine direction (MD).

[0045] The polyethylene resin that constitutes the sealant layer 18, which exhibits such tear resistance, is preferably C4-LLDPE, for example. C4-LLDPE is a type of LLDPE (linear low-density polyethylene) composed of a copolymer of ethylene and 1-butene. Its molecular structure consists of a main chain of LLDPE derived from ethylene and a side chain with four carbon atoms derived from 1-butene. Compared to C6-LLDPE and C8-LLDPE, C4-LLDPE has shorter side chains and a lower melt flow rate (MFR), resulting in lower tensile impact strength, tensile strength, and tensile modulus. Therefore, by using C4-LLDPE as the polyethylene resin that constitutes the sealant layer 18, it is possible to easily impart tear resistance in the machine direction of the sealant layer 18.

[0046] The melt flow rate (MFR) of the sealant layer 18 is less than 5 g / 10 minutes, preferably 0.5 g / 10 minutes or more and less than 5 g / 10 minutes, and more preferably 2 g / 10 minutes or more and less than 5 g / 10 minutes. A melt flow rate of less than 5 g / 10 minutes increases the melt tension, which helps prevent wrinkles during processing such as inflation. Specifically, by slightly preventing the sealant layer 18 from flowing during heating to melt it, a smooth and transparent film can be produced.

[0047] The melting point of the sealing layer 18 is, for example, in the range of 100 to 170° C., preferably 120° C. or less, and more preferably 95 to 110° C. The sealing layer 18 is preferably made of a material having a density of less than 0.925 g / cm 3 (More preferably 0.900 to 0.920 g / cm 3 As an example, the above-mentioned linear low-density polyethylene (LLDPE) can be used, as long as it can impart easy tearing in the mechanical direction of the sealing layer 18, ultra-low-density polyethylene (VLDPE) can be used, and a material obtained by mixing LLDPE and VLDPE can also be used.

[0048] As part or all of the polyethylene constituting sealant layer 18, biomass polyethylene, made from biomass-derived ethylene, may be used. Such a sealant film is disclosed, for example, in Japanese Patent Application Laid-Open No. 2013-177531. Sealant layer 18 may also comprise mechanically recycled polyethylene made from used polyethylene products or resin generated during the polyethylene product manufacturing process (so-called flash).

[0049] (Other layers)

[0050] The laminate film 16 may also include an adhesive layer (not shown) between the substrate 17 and the sealant layer 18. The adhesive forming the adhesive layer can be selected based on the bonding method, and urethane adhesives, polyester adhesives, etc. can be used. The provision of such an adhesive layer improves the interlayer adhesion between the substrate 17 and the sealant layer 18, preventing delamination and maintaining the pressure and impact resistance of the pouch.

[0051] The adhesive layer is preferably chlorine-free. Chlorine-free adhesive layers can prevent discoloration of the adhesive and recycled resin after recycling, or the generation of odors due to heat treatment. From an environmental perspective, the adhesive layer is preferably made of a biomass material. Furthermore, the polyethylene can be bio-based polyethylene. From an environmental perspective, the adhesive is preferably solvent-free.

[0052] For example, from the perspective of improving the gas barrier properties against water vapor and oxygen, the laminate film 16 may further include a gas barrier layer. The gas barrier layer may be provided between the substrate 17 and the sealing layer 18, or may be provided on the surface of the substrate 17 opposite to the sealing layer 18. The water vapor permeability of the laminate is, for example, 5 g / m 2 day, or 1g / m 2 Less than 0.5g / m 2 The oxygen permeability of the laminated film 16 is, for example, 1 cc / m 2 ·atm·day, or 0.5g / m 2 Less than 0.2g / m2 2 Atm·day or less. Since the laminated film 16 includes a gas barrier layer, the contents are protected from degradation due to water vapor and oxygen, and the quality is easily maintained for a long time.

[0053] As an example of a gas barrier layer, a vapor-deposited layer of an inorganic oxide can be cited. By using a vapor-deposited layer of an inorganic oxide, a high barrier property can be obtained with an extremely thin layer in a range that does not affect the recyclability of the laminate. As an inorganic oxide, for example, aluminum oxide, silicon oxide, magnesium oxide, tin oxide, etc. can be cited. From the viewpoint of transparency and barrier properties, as an inorganic oxide, a group consisting of aluminum oxide, silicon oxide and magnesium oxide can be selected. The thickness of the vapor-deposited layer of the inorganic oxide can be, for example, set to be greater than 5 nm and less than 100 nm, or greater than 10 nm and less than 50 nm. By having a thickness of more than 5 nm, it is easy to exert barrier properties well, and by having a thickness of less than 100 nm, it is easy to maintain the flexibility of the laminate. The vapor-deposited layer can be formed, for example, by physical vapor deposition, chemical vapor deposition, etc.

[0054] The laminated film 16 may also include a metal layer (metal foil) instead of the vapor-deposited layer of the inorganic oxide, or further include a metal layer (metal foil) on the basis of the vapor-deposited layer of the inorganic oxide. As the metal layer, various metal foils composed of aluminum, stainless steel, etc. can be used. Among them, aluminum foil is preferred from the aspects of moisture resistance, ductility, processability, cost, etc. As the aluminum foil, general soft aluminum foil can be used. Among them, iron-containing aluminum foil is preferred from the aspects of pinhole resistance and excellent ductility during molding. In the case of providing a metal layer, its thickness can be 7 to 50 μm, or 9 to 15 μm, considering the aspects of barrier properties, pinhole resistance, processability, etc.

[0055] The laminate film 16 may also include an anchor coating layer between the substrate 17 and the sealant layer 18. The anchor coating layer may be an extremely thin layer that does not affect the recyclability of the laminate film 16 and can be formed using an anchor coating agent. Examples of anchor coating agents include acrylic resins, epoxy resins, acrylic urethane resins, polyester polyurethane resins, polyether polyurethane resins, and polyvinyl alcohol resins. From the perspective of heat resistance and interlayer adhesive strength, acrylic urethane resins and polyester polyurethane resins are preferred as anchor coating agents.

[0056] The laminated film 16 may also include a printed layer, for example. The printed layer may be provided between the substrate 17 and the sealing layer 18, or may be provided on the surface of the substrate 17 opposite the sealing layer 18. When a printed layer is provided, it is preferred that the printing ink be chlorine-free to prevent discoloration or odor generation during remelting of the printed layer. Furthermore, from an environmental perspective, it is preferred that the compounds contained in the printing ink be made of biomass materials.

[0057] Next, refer to Figure 1 and Figure 3 The nozzle 20 mounted on the upper end portion 11 of the housing portion 10 formed of the laminated film 16 will be described. Figure 3 (a) is a front view showing the spout 20 of the spouted packaging bag 1. Figure 3 (b) is a view of the nozzle 20 from below (base side). Figure 1 and Figure 3 As shown, the mouth 20 has: a pouring tube 21, along a direction (first direction, Figure 1 and Figure 3 The pouring tube 21 includes a base 22 extending in the vertical direction (a); a flange 23 provided at one end (lower end) of the pouring tube 21; a cap 24 screwed into an external thread provided on the outside of the pouring tube 21 to close the other end (upper end) of the pouring tube 21. A pouring path 25 is provided on the inner side extending from the upper end of the pouring tube 21 to the lower end of the base 22, extending through the center thereof. This allows the contents of the spouted packaging bag 1 to be poured out of the bag. It should be noted that the spout 20, like the laminated film 16 described above, can be formed of, for example, polyethylene resin.

[0058] like Figure 3 As shown in (b), the base 22 has, for example, a triangular portion 23a and an arcuate portion 23b, with the aforementioned pouring path 25 formed inside. The base 22 serves as the portion to which the sealing layer 18 of the laminated film 16 is welded when the nozzle 20 is assembled in the container 10. The sealing layers 18 are welded to each other on both sides of the base 22. It should be noted that a plurality of ribs may be provided on the surface of the base 22 to which the sealing layer 18 is welded to support the welding of the sealing layer 18. Such ribs may, for example, extend in the transverse direction.

[0059] Here, refer to Figure 4 and Figure 5 The structure for welding the nozzle 20 to the region of the laminated film 16 will be described in detail. Figure 4 1 is an enlarged front view showing the vicinity of the welded portion of the spout 20 in the spouted packaging bag 1. Figure 4 As shown, in the spouted packaging bag 1 of this embodiment, the sealant layer 18 of the laminate film 16 is welded to the base 22 of the spout 20 at the upper end portion 11 of the container portion 10. Furthermore, the sealant layers 18 are welded to each other beside (at both edges of) the base 22. Specifically, during the welding of the spout 20, the sealant layers 18 are welded to each of the front and back sides of the spout 20, and these opposing sealant layers 18 are directly welded to each other on both sides of the spout 20.

[0060] Furthermore, in the spout packaging bag 1 of the present embodiment, the width D1 along the vertical direction of the first welded area R1 where the sealing layer 18 is welded to the base 22 is shorter than the width D2 along the vertical direction of the second welded area R2 where the sealing layers 18 are welded to each other, and a step S is formed between the first welded area R1 and the second welded area R2. The step S is, for example, a small step having a dimension in the vertical direction of not less than 1.5 mm and not more than 5 mm. In addition, the dimension of the step S in the vertical direction can also be specified as a ratio relative to the dimension of the base, and can be 0.15 to 0.6 relative to the length of the base 22 in the vertical direction (equivalent to D1), or can be 0.1 to 0.5 relative to the lateral width of the base 22 in the lateral direction (second direction) perpendicular (intersecting) to the vertical direction. The length of the base 22 in the vertical direction is, for example, 7 to 12 mm, and the lateral width of the base 22 in the lateral direction is, for example, 15 to 45 mm. In this way, the step S becomes a tiny step relative to the dimension and length of the base 22, etc. It should be noted that in Figure 4 In the embodiment, the upper end of the first weld region R1 is along the lower end of the flange 23 of the nozzle 20 , but the laminate film 16 may be welded to the nozzle 20 so that the upper end of the first weld region R1 is slightly separated from the lower end of the flange 23 .

[0061] Next, refer to Figure 5 The cross-sectional shape of the packaging bag in the vicinity of the minute step S will be described. Figure 5 Yes Figure 4 A cross-sectional view of a cross section near the welded portion of the nozzle shown. Figure 5As shown, at the step S below the nozzle 20 (base 22), the opposing layers of the laminated film 16 (sealant layer 18) are recessed inward, forming a recessed region R3. This is due to the following: when the laminated film 16 is welded to the nozzle 20, the laminated film 16 at both ends of the nozzle 20 is heated and softened while being subjected to tension. After heating, this tension causes the film to move inward (shrink) on both the top and bottom sides. This recessed region R3 protects the welded region between the nozzle 20 (base 22) and the sealant layer 18 of the laminated film 16. It should be noted that the laminated films 16 at the step S are not welded to each other.

[0062] Here, refer to Figures 5 to 7 The difference in cross-sectional shape between a case where a step S is provided between the first weld region R1 and the second weld region R2 as in the present embodiment and a case where no step is provided between the first weld region R1 and the second weld region R2 (comparative example) and the effects of the difference in shape will be described. Figure 6 (a) is an enlarged front view showing the vicinity of the welded portion of the spout of a conventional spout packaging bag. Figure 6 (b) is Figure 6 (a) is a cross-sectional view of . Figure 7 (a) is a diagram for explaining the pressure applied when a spouted packaging bag of a conventional example is filled with content (liquid). Figure 7 (b) is a diagram for explaining pressure applied when the spouted packaging bag of the present embodiment is filled with content (liquid).

[0063] like Figure 6 As shown, in the conventional example of the spouted packaging bag 101, welding is performed in a manner that no step is provided between the first welding area R11 where the sealing layer 18 of the laminated film 16 is welded to the nozzle 20 (base) and the second welding area R12 where the sealing layers 18 of the laminated film 16 are welded to each other. That is, the welding width of the first welding area R11 of the nozzle 20 is approximately the same as the welding width of the second welding area R2 where the sealing layers are welded to each other. In this case, the opposing laminated films 16 (sealing layers 18) will not be stretched to each other, and therefore will not become a shape that is concave (contracted) inwardly as in the spouted packaging bag 1 of the present embodiment. In such a conventional example of the spouted packaging bag 101, as Figure 7As shown in (a), when pressure is applied to the contents of the spouted packaging bag 101, the pressure from the contents is evenly applied to both the first welded region R11 and the second welded region R12. In this conventional spouted packaging bag 101, since a laminated film 16 made of a single material is used, it is difficult to improve the seal strength near the spout, where welding is difficult (due to stringent manufacturing conditions). This easily reduces the seal strength, and as a result, the pressure resistance may also be reduced.

[0064] On the other hand, Figure 5 As shown in FIG. 1 , in this embodiment, a step D is provided between the first weld region R1 and the second weld region R2 near the weld region of the nozzle 20. Therefore, when the portion of the laminated film 16 located at the lower portion of the nozzle 20 (step D) is heated, the portion of the laminated film 16 made of a single material softens and deforms inwardly by shrinking. Since the laminated film 16 is thus concave (shrinking), even when pressure is applied by placing the contents in the packaging bag, as in FIG. Figure 7 As shown in (b), pressure is less likely to be applied to the portion where the sealant layer 18 is welded to the nozzle 20 (the nozzle end, first welded region R1), and instead is applied to the portion where the sealant layer 18 is welded to each other (second welded region R2). In other words, by making the laminate film 16 recessed inward, the pressure of the contents (liquid) is directed toward the second welded region R2. Thus, this spouted packaging bag 1 improves pressure resistance even when using a laminate film made of a single material.

[0065] Next, a method for manufacturing such a spouted packaging bag 1 is described. In this manufacturing method, multiple laminate films 16 having a base material 17 and a sealant layer 18 made of the same material are first prepared. Each laminate film 16 includes a portion having a shape corresponding to the outer shape of the container 10 of the spouted packaging bag 1 (e.g., a rectangular shape). Furthermore, a spout 20 is prepared, including a pouring tube 21 and a base 22 provided at one end of the pouring tube 21. The base 22 of the spout 20 is then positioned on the sealant layer 18 corresponding to the upper end 11 of one laminate film 16, and the sealant layer 18 of another laminate film 16 corresponding to the upper end 11 is positioned above the base 22 of the spout 20. This creates a configuration in which the spout 20 is sandwiched between the laminate films 16. The portion corresponding to the upper end 11 is then heat-sealed, thereby fusing the sealant layer 18 of the laminate film 16 to the base 22 of the spout 20 and fusing the sealant layers 18 to each other near the base 22. At this time, the welding can be performed simultaneously with the lower end portion 12 and the side portions 13 and 14, or at different times. It should be noted that when the spouted packaging bag 1 is a self-standing bag, in addition to a pair of laminated films 16, a bottom film (with the same layer structure as the laminated film 16) folded in half can also be arranged on the lower end side and welded. The heat sealing temperature is a temperature above the melting point of the sealing layer 18, for example, in the range of 120 to 170°C. In addition, in the manufacturing method of the spouted packaging bag 1 of this embodiment, when welding, the width D1 of the first welded area R1 where the sealing layer 18 is welded to the base 22 is shorter than the width D2 of the second welded area R2 where the sealing layers 18 are welded to each other, and a step S is formed between the first welded area R1 and the second welded area R2.

[0066] As described above, in the spout packaging bag 1 of this embodiment, a step S is provided between the first welded region R1 where the sealing layer 18 is welded to the base 22 of the spout 20 and the second welded region R2 where the sealing layers 18 are welded to each other. By providing such a step S, when the portion of the laminated film 16 located below the spout 20 (step S) is heated (during manufacturing), the film portion softens and deforms inwardly by shrinking (see FIG. Figure 5 Furthermore, due to the concave structure of the laminated film 16, when the contents are placed in the packaging bag, the pressure of the contents that should be applied to the portion where the sealing layer 18 is welded to the nozzle 20 (the end of the nozzle) becomes difficult to apply, and the stress is dispersed to the portion other than this portion, and the pressure is directed toward the region where the sealing layers 18 are welded to each other located next to the nozzle (see Figure 7 (b)). The seal strength between the second welded regions R2 of the sealing layers 18 is higher than the seal strength between the first welded regions R1 of the sealing layers 18 and the spout 20 (base 22). Thus, the spouted packaging bag 1 can improve pressure resistance even when using a laminated film made of a single material.

[0067] Furthermore, in the spouted packaging pouch 1 of this embodiment, the dimension of the step S in the vertical direction may be 1.5 mm or greater. In this case, the portion of the laminated film 16 located below the spout 20 (step S) can be more reliably deformed to contract inward, thereby distributing pressure. Thus, the spouted packaging pouch 1 can more reliably improve pressure resistance even when using a laminated film 16 made of a single material.

[0068] Furthermore, in the spouted packaging bag 1 of this embodiment, the dimension of the step S along the vertical direction may be 5 mm or less. The portion of the step S between the first welded region R1 where the sealing layer 18 is welded to the base 22 of the spout 20 and the second welded region R2 where the sealing layer 18 is welded to each other constitutes the flow path when the contents contained in the container 10 are poured out from the pouring tube 21 of the spout 20. As described above, the portion of the laminate film 16 corresponding to the step S is structured to be inwardly constricted, narrowing the flow path. Therefore, in this spouted packaging bag 1, the length of the step S is set to 5 mm or less. Consequently, this spouted packaging bag 1 facilitates pouring the contents of the packaging bag.

[0069] Furthermore, in the spouted packaging pouch 1 of this embodiment, the vertical dimension of the step S may be 0.15 to 0.6 relative to the vertical length of the base 22. In this case, by having the step S dimension of 0.15 or greater relative to the length of the base 22, the portion of the laminated film 16 located below the spout 20 (the step S) deforms inwardly, similarly to the above description, thereby distributing pressure. This more reliably improves the pressure resistance even when using a laminated film 16 made of a single material. Furthermore, by having the step S dimension of 0.6 or less relative to the length of the base 22, the flow path can be prevented from being excessively long, allowing for easier pouring of the contents of the packaging pouch.

[0070] Furthermore, in the spouted packaging pouch 1 of this embodiment, the dimension of the step S in the vertical direction may be 0.1 to 0.5 times the width of the base 22 in a lateral direction perpendicular to the vertical direction. In this case, by having the dimension of the step S be 0.1 or greater relative to the lateral width of the base 22, the portion of the laminate film 16 located below the spout 20 (the step S) deforms inwardly, thereby distributing pressure, similarly to the above description. This more reliably improves the pressure resistance even when using a laminate film 16 made of a single material. Furthermore, by having the dimension of the step S be 0.5 or less relative to the lateral width of the base 22, similarly to the above description, the flow path can be prevented from being excessively long, allowing for easier pouring of the contents of the packaging pouch.

[0071] Furthermore, in the spouted packaging pouch 1 of this embodiment, it is preferable that the base material 17 and the sealant layer 18 be made of the same material, polyethylene resin or polypropylene resin. Using such a material facilitates softening during welding, allowing the portion of the laminate film 16 located below the spout 20 (step S) to be more reliably deformed to contract inward when heated. This improves compressive strength even when using a laminate film made of a single material.

[0072] Furthermore, in the spouted packaging pouch 1 of this embodiment, the base material 17 and the sealant layer 18 may be made of the same material, polyethylene resin, with the polyethylene resin comprising 90% by mass or greater of the laminated film 16. In this case, softening during welding is further facilitated, and when the portion of the laminated film 16 located below the spout 20 (step S) is heated, the portion of the film can be more reliably deformed to contract inward. This improves compressive strength even when using a laminated film constructed from a single material.

[0073] Furthermore, in the spouted packaging pouch 1 of this embodiment, the receiving portion 10 is formed such that the opposing sealant layers 18 are recessed inward at the step S between the first welded region R1 and the second welded region R2. In this manner, even when pressure is applied by the contents being placed in the packaging bag, the pressure is less likely to be applied to the first welded region R1 (the end of the spout 20) where the sealant layers 18 are welded to the spout 20. Instead, the pressure is dispersed to the welded portion of the sealant layers 18. Consequently, the spouted packaging pouch 1 can improve pressure resistance even when using a laminated film made of a single material.

[0074] Furthermore, in the method for manufacturing the spouted packaging bag 1 of this embodiment, during the welding step, the width D1 of the first welded region R1 where the sealant layer 18 is welded to the base 22 is shorter than the width D2 of the second welded region R2 where the sealant layers 18 are welded together, and a step S is formed between the first welded region R1 and the second welded region R2. This step S softens the portion of the laminate film 16 located below the spout 20 (step S) when heated, causing it to deform inward by contracting. Because of this concave structure, even when pressure is applied after the contents are placed in the packaging bag, the pressure is less likely to be applied to the first welded region R1 where the sealant layer 18 is welded to the spout 20 (the end of the spout 20). Instead, the pressure is applied to the second welded region R2 where the sealant layers 18 are welded together. Consequently, this method for manufacturing a spouted packaging bag achieves improved pressure resistance even when using a laminate film made of a single material.

[0075] Furthermore, if one attempts to manufacture a spouted packaging bag without a step, as in conventional structures, using a laminated film with a single material structure, the manufacturing conditions (the range of sealing temperature conditions) required to achieve seal strength and pressure resistance above specified values ​​are extremely narrow (see also the comparative examples described below). Consequently, conventional manufacturing methods reduce productivity. However, the manufacturing method for the spouted packaging bag 1 of this embodiment, due to its bag structure that easily improves pressure resistance, can broaden the range of manufacturing conditions required to achieve seal strength and pressure resistance above specified values, thereby improving productivity and yield rates.

[0076] Furthermore, in the method for manufacturing a spouted packaging bag of this embodiment, the width of the step S is preferably 1.5 mm to 5 mm. By making the step S 1.5 mm or wider, the portion of the laminate film 16 located below the spout 20 (step S) can be more reliably deformed to contract inward. Thus, according to the spouted packaging bag 1, even when using a laminate film 16 made of a single material, pressure resistance can be more reliably improved. On the other hand, by making the step S 5 mm or narrower, as described above, the length of the narrow flow path can be limited, thereby facilitating the pouring of the contents of the packaging bag.

[0077] While the embodiments of the present invention have been described in detail above, the present invention is not limited to these embodiments. For example, in the above embodiments, the nozzle 20 is located at the center of the upper end 11 of the container 10. However, this is not limiting. For example, the nozzle 20 may be located at the corner between the upper end 11 and the side portion 13 of the container 10. Even with such a configuration, the same functional effects can be achieved.

[0078] [Example]

[0079] Hereinafter, the present invention will be described in more detail using Examples and Comparative Examples, but the present invention is not limited to the following Examples.

[0080] <Example 1>

[0081] As Example 1, a Figure 1 The spouted packaging bag 1 of the structure shown and the test piece corresponding to the vicinity of the welded portion of the spouted packaging bag 1 (see Figure 8, measuring piece). In the spouted packaging bag 1 and the test piece, the size of the step S is 3 mm. In addition, the welding width of the first welded area R1 of the upper end portion 11 is 8 mm, and the welding width of the second welded area R2 is 12 mm. The first welded area R1 is formed as a flange 23 slightly away from the nozzle 20. It should be noted that the lateral width of the base 22 of the nozzle 20 is 18 mm, and the lateral width of the welded portion in the test piece is 15 mm. The packaging bag and test piece of the above structure were produced by welding the laminate film 16 at a sealing temperature serving as a reference and temperatures (±10°C, ±20°C, ±30°C) above and below the sealing temperature serving as a reference. The sealing strength was evaluated using the produced test piece. In addition, the pressure resistance was evaluated using the produced packaging bag. The sealing strength and pressure resistance were evaluated by the following method.

[0082] [Seal strength]

[0083] Prepare a test piece with a welded area of ​​about 15 mm in sample width (see Figure 8 ), and a T-type peel test was performed at a tensile speed of 300 mm / min. This T-type peel test was conducted according to the method in accordance with JIS K7127. In this test, products with a strength of 10 N / 15 mm or greater and a film break at the peeling interface were considered acceptable and rated A. On the other hand, products with a strength of less than 10 N / 15 mm or a surface separation between the film and the nozzle were considered unacceptable and rated B.

[0084] [Withstand pressure test]

[0085] In the pressure test, 50°C hot water was poured into the prepared spouted packaging pouch 1, and an internal pressure of 80 kgf was applied for 3 minutes. In this test, if no leakage occurred, the pouch was deemed acceptable and rated A. On the other hand, if leakage occurred, the pouch was deemed unacceptable and rated B.

[0086] Table 1 below shows the test results of seal strength and pressure resistance when heat sealing was performed at a reference sealing temperature (hereinafter referred to as 0 (reference temperature)) and temperatures above and below the reference sealing temperature (Example 1).

[0087] [Table 1]

[0088] Sealing temperature (℃) Seal strength Compressive strength -30 B B -20 A A -10 A A O(base temperature) A A 10 A A 20 A A 30 B B

[0089] <Example 2>

[0090] In Example 2, except that the size of the step S was set to 2 mm, the spouted packaging bag 1 and the corresponding test piece (see Figure 8), and the sealing strength and pressure resistance were evaluated. It should be noted that in Example 2, the welding width of the first welding region R1 was 8 mm.

[0091] Table 2 below shows the test results of seal strength and pressure resistance when heat sealing was performed at a reference sealing temperature (hereinafter referred to as 0 (reference temperature)) and temperatures above and below the reference sealing temperature (Example 2).

[0092] [Table 2]

[0093] Sealing temperature (℃) Seal strength Compressive strength -30 B B -20 B A -10 A A 0 (base temperature) A A 10 A A 20 A B 30 B B

[0094] Comparative Example

[0095] In the comparative example, the spouted packaging bag 101 was produced without providing the step S between the first welded region R1 and the second welded region R2 (see FIG. Figure 6 ) and a test piece corresponding to the spouted packaging bag 101. The spouted packaging bag 101 and test piece do not have a step S. The weld width of the first welded region R11 at the upper end 11 is 8 mm, and the weld width of the second welded region R12 is 8 mm. Note that the lateral width of the base 22 of the spout 20 is 18 mm, and the lateral width of the welded portion of the test piece is 15 mm. In this comparative example, the sealing strength and compressive strength of the prepared packaging bag and test piece were evaluated in the same manner as in Examples 1 and 2.

[0096] Table 3 below shows test results of seal strength and pressure resistance when heat sealing was performed at a reference sealing temperature (hereinafter referred to as 0 (reference temperature)) and temperatures above and below the reference sealing temperature (Comparative Examples).

[0097] [Table 3]

[0098] Sealing temperature (℃) Seal strength Compressive strength -30 B B -20 B B -10 B A 0 (base temperature) A A 10 B B 20 B B 30 B B

[0099] As shown in Examples 1 and 2, as well as the Comparative Example, the provision of a step S between the first welded region R1 and the second welded region R2 facilitates improvements in the sealing strength and pressure resistance of the spouted packaging bag 1. Furthermore, it was confirmed that, when the spout is welded without a step, as in the Comparative Example, strict sealing temperature conditions are required to achieve sealing strength and pressure resistance above the specified values. Consequently, when spouted packaging bags are manufactured using a laminated film with a single material structure, the yield rate decreases, leading to poor manufacturing efficiency. In contrast, the provision of a step S, as in the spouted packaging bag 1 of this embodiment, broadens the range of permissible sealing temperature conditions for bag production. Therefore, it was confirmed that this structure can improve both the yield rate and manufacturing efficiency.

[0100] Description of reference numerals:

[0101] 1: Packaging bag with a spout; 10: Receiving portion; 11: Upper end portion (edge); 16: Laminated film; 17: Base material; 18: Sealing layer; 20: Spout; 21: Pour-out tube; 22: Base; D1, D2: Width; R1: First welded area; R2: Second welded area; R3: Recessed area; S: Step.

Claims

1. A packaging bag with a spout, wherein: have: a housing portion formed of a laminated film having a base material and a sealing layer formed of the same material; as well as The spout includes a pouring tube extending in a first direction and a base provided at one end of the pouring tube, wherein the spout is mounted on the edge of the container. At the edge of the housing portion, the sealing layer is welded to the base of the nozzle, and the sealing layers are welded to each other beside the base. A first weld region where the sealing layer is welded to the base has a width along the first direction shorter than a second weld region where the sealing layers are welded to each other, and a step is formed between the first weld region and the second weld region.

2. The spouted packaging bag according to claim 1, wherein: A dimension of the step along the first direction is greater than or equal to 1.5 mm.

3. The spouted packaging bag according to claim 1 or 2, wherein: A dimension of the step along the first direction is 5 mm or less.

4. The spouted packaging bag according to any one of claims 1 to 3, wherein A dimension of the step along the first direction is 0.15 to 0.6 relative to a length of the base along the first direction.

5. The spouted packaging bag according to any one of claims 1 to 4, wherein A dimension of the step along the first direction is 0.1 to 0.5 relative to a lateral width of the base along a second direction intersecting the first direction.

6. The spouted packaging bag according to any one of claims 1 to 5, wherein The same material constituting the base material and the sealing layer is polyethylene resin or polypropylene resin.

7. The spouted packaging bag according to any one of claims 1 to 6, wherein The same material constituting the base material and the sealing layer is polyethylene resin, The content of the polyethylene resin in the entire laminated film is 90% by mass or more.

8. The spouted packaging bag according to any one of claims 1 to 7, wherein The accommodation portion is formed such that the facing sealing layers are recessed inwardly at the step between the first weld region and the second weld region.

9. A method for manufacturing a spouted packaging bag, wherein: With the following processes: preparing a laminated film having a base material and a sealing layer composed of the same material; preparing a spout having a pouring tube and a base provided on one end side of the pouring tube; as well as The sealing layer of the laminated film is welded to the base of the nozzle, and the sealing layers are welded to each other beside the base. In the welding step, the width of a first welding region where the sealing layer is welded to the base is shorter than the width of a second welding region where the sealing layers are welded to each other, and a step is formed between the first welding region and the second welding region.

10. The method for manufacturing a spouted packaging bag according to claim 9, wherein: The width of the step is 1.5 mm to 5 mm.

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