JP2024063424A - Stopper, pouch with stopper, and method for manufacturing pouch with stopper - Google Patents

Abstract

[Problem] To provide a spout that can prevent a gap from being generated between the spout and a film sheet when the spout and the film sheet are welded together, and a spouted pouch and a method for manufacturing the spouted pouch using the spout. [Solution] The spout 20 comprises a substantially cylindrical main body 20a and a welded portion 22s disposed on the outer circumferential surface of the main body 20a, and the melting point of the resin forming the welded portion 22s is lower than the melting point of the resin forming the main body 20a. The spouted pouch comprises the spout 20 and a film sheet heat-sealed into a bag shape, and the welded portion 22s of the spout 20 and the film sheet are heat-sealed together. [Selected Figure] Figure 2

Description

The present invention relates to a spout, a pouch with a spout, and a method for manufacturing a pouch with a spout.

There are pouches with stoppers that are made by heat-sealing a stopper made of resin and a pouch made of a film sheet shaped like a bag. The contents can be sealed and stored by filling the filling space inside the pouch with a beverage or other contents and closing the stopper with a cap. The cap can also be opened to easily drink the filled beverage from the stopper.

Patent Document 1 describes a liquid-filled container as an example of a spouted pouch. The liquid-filled container described in Patent Document 1 has a contents removal device fixed to the upper opening of a bag-shaped container body that is filled with contents such as liquid. The bag-shaped container body is made from a laminated film of polyester film, aluminum foil, stretched nylon film, and polyethylene film. The contents removal device has a mouth and a conduit part that is integrally connected to the mouth, and an opening is formed in a part close to the upper end of the conduit part.

When using the content removal device as a straw, the opening of the conduit is closed by the wall of the bag-shaped container body when you put your mouth to the opening and suck, and the content is sucked up from the bottom end of the conduit. When using the content removal device as a spout, holding the bag-shaped container body in your hand and tilting it causes the opening of the conduit to act as an intake port, allowing you to remove the contents of the bag-shaped container body down to the last drop.

Japanese Utility Model Publication No. 02-021399

However, the liquid-filled container described in Patent Document 1 has poor recyclability because it uses a laminated film made of nylon, aluminum, or the like as the material for the pouch (bag-shaped container body).

High-density polyethylene (HDPE), which has high rigidity, is often used as the material for the stopper. Furthermore, to improve recyclability, there is a demand for film sheets made of a single material. When a film sheet made of a single material is used as the material for the pouch, low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE) is used as the material for the film sheet because of its ease of heat sealing. The melting points of low-density polyethylene (LDPE) and linear low-density polyethylene (LLDPE) are lower than that of high-density polyethylene (HDPE).

Therefore, in order to adequately heat seal the stopper and the film sheet, it is necessary to heat the film sheet at a temperature higher than the melting point of the film sheet. Since a film sheet made of a single material such as polyethylene has a lower rigidity than a laminated film made of nylon or aluminum, when a stopper made of high density polyethylene (HDPE) is heat sealed with a film sheet made of low density polyethylene (LDPE) or linear low density polyethylene (LLDPE), the film sheet may shrink due to the heating temperature and heating time required to melt the stopper, which has a high melting point, and wrinkles may occur in the film sheet. As a result, a gap may be formed between the stopper and the film sheet, and the filled contents may leak to the outside. In addition, there is a concern that the appearance may deteriorate due to the occurrence of wrinkles, and that the contents may deteriorate due to the intrusion of oxygen, etc. from the outside into the pouch.

In light of the above circumstances, the present invention aims to provide a spout that can prevent gaps from occurring between the spout and the film sheet when the spout and the film sheet are welded together, a spouted pouch using the spout, and a method for manufacturing a spouted pouch.

In order to solve the above problems, the present invention proposes the following means.
The plug of the present invention comprises a substantially cylindrical main body portion and a weld portion arranged on the outer peripheral surface of the main body portion, and the melting point of the resin forming the weld portion is lower than the melting point of the resin forming the main body portion.

In the above plug, the melting point of the resin forming the welded portion may be at least 10°C lower than the melting point of the resin forming the main body portion.

In the above plug, the main body may include high-density polyethylene, and the welded portion may include linear low-density polyethylene or low-density polyethylene.

The spout-equipped pouch of the present invention comprises the spout and a film sheet heat-sealed into a bag shape, and the welded portion of the spout and the film sheet are heat-sealed.

In the above-mentioned spouted pouch, the film sheet may be made of a single material.

In the above-mentioned spouted pouch, the melting point of the resin forming the welded portion may be a temperature lower than the melting point of the resin forming the film sheet.

In the above-mentioned spouted pouch, the upper limit of the melting point of the resin forming the welded portion may be 5°C lower than the melting point of the resin forming the film sheet, and the lower limit of the melting point of the resin forming the welded portion may be 15°C lower than the melting point of the resin forming the film sheet.

In the above-mentioned spouted pouch, the film sheet may contain linear low-density polyethylene or low-density polyethylene.

The method for manufacturing a spouted pouch of the present invention includes a spout supplying step for forming a spout having a main body and a welded part made of a resin having a melting point lower than that of the resin forming the main body, and a heat sealing step for welding the welded part to a bag-shaped film sheet.

In the above-mentioned method for manufacturing a pouch with a spout, the film sheet may be made of a single material.

In the above-mentioned method for manufacturing a spouted pouch, the melting point of the resin forming the welded portion may be a temperature equal to or lower than the melting point of the resin forming the film sheet, and the temperature to which the welded portion and the film sheet are heated in the heat sealing step may be a temperature equal to or lower than the melting point of the resin forming the film sheet.

The stopper and the pouch with stopper of the present invention can provide a stopper that can prevent a gap from being generated between the stopper and the film sheet when the stopper and the film sheet are welded together, as well as a pouch with stopper that uses the stopper and a method for manufacturing the pouch with stopper.

FIG. 1 is a perspective view of a spouted pouch according to an embodiment of the present invention. 1A and 1B are a front view and a side view of a plug according to an embodiment of the present invention. 4 is a cross-sectional view of the heat-sealed spout and film sheet of the spout-equipped pouch. FIG. 1 is a flowchart showing a method for manufacturing a spouted pouch according to the present embodiment. 4A to 4C are diagrams illustrating a method for manufacturing the same spouted pouch.

One embodiment of the present invention will be described with reference to Figures 1 to 5.

FIG. 1 is a perspective view of a spouted pouch 100 according to the present embodiment.
The spouted pouch 100 includes a pouch 10, a spout 20, and a cap 30. The spouted pouch 100 is sealed by connecting the bag-shaped pouch 10 and the spout 20 by heat sealing, filling the filling space 10s of the pouch 10 with a beverage or other content, and closing the spout 20 with the cap 30, so that the content does not leak out of the spouted pouch 100. A user can release the sealed state by opening the cap 30 and drink the beverage content through the spout 20.

The spout 20 is sandwiched between the opposing film sheets that make up the pouch 10, and the pouch 10 and the spout 20 are welded together by applying pressure and heat from both sides of the direction in which the spout 20 is sandwiched. The spout-equipped pouch 100 is a standing pouch container with a bottom, and can be placed on a desk or the like with the spout 20 facing up.

In this embodiment, as shown in FIG. 1, the vertical direction of the spouted pouch 100 with the spout 20 facing up is defined as the "vertical direction V", the vertical upward direction is defined as the "upper side UP" in the vertical direction V, and the vertical downward direction is defined as the "lower side LO" in the vertical direction V. In addition, the direction in which pressure is applied when the pouch 10 and the spout 20 are heat-sealed is defined as the "depth direction D", one side in the depth direction D is defined as the "front side FR", and the other side in the depth direction D is defined as the "rear side RR". In addition, the direction perpendicular to the vertical direction V and the depth direction D is defined as the "horizontal direction H", one side in the horizontal direction H is defined as the "left side LT", and the other side in the horizontal direction H is defined as the "right side RT".

The pouch 10 comprises a filling space 10s, a film sheet 11, a top seal portion 12, a side seal portion 13, and a bottom seal portion 14. The filling space 10s is a space surrounded by the film sheet 11, and is a space into which the contents of the spouted pouch 100 are filled.

The film sheet 11 is a sheet-shaped resin film formed from a single material (mono-material) resin. Low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE) can be used as the material of the film sheet 11. The material of the film sheet 11 is not limited to low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE), and may be any material suitable for heat sealing (thermal welding). The film sheet 11 may be a single-layer film made of a single material, or a multi-layer film made of a single material in which resins of the same type are laminated. By forming the film sheet 11 from a single material, recyclability can be improved. The film sheet 11 may be printed with a product name or logo in advance.

The film sheet 11 includes a front film 11a, a rear film 11b, and a bottom film 11c. The front film 11a is disposed on the front side FR of the pouch 10. The rear film 11b is disposed on the rear side RR of the pouch 10. The front film 11a and the rear film 11b are substantially rectangular and have a shape sufficient to cover the contents filled in the filling space 10s of the pouch 10.

The pouch 10 is formed into a bag shape by heat-sealing the front film 11a and the rear film 11b opposed to each other in the depth direction D at the top seal section 12 and the side seal section 13, and then heat-sealing the front film 11a, the rear film 11b, and the bottom film 11c folded in half and sandwiched between them at the bottom seal section 14. The pouch 10 may be formed by folding and heat-sealing a single film sheet 11, or may be formed by connecting a plurality of film sheets 11 by heat sealing. When the spouted pouch 100 does not have a bottom surface, the pouch 10 does not need to include the bottom film 11c.
The pouch 10 may also be of a gusset type having a folding member folded in half and sandwiched between the front film 11a and the rear film 11b at the side.

The top seal portion 12 is a portion where the front film 11a, the rear film 11b, and the spout 20, which face each other in the depth direction D, are heat-sealed, and is located at the end of the upper side UP of the pouch 10. The horizontal seal portion 13 is a portion where the front film 11a and the rear film 11b, which face each other in the depth direction D, are heat-sealed, and is located at the end of the left side LT and the right side RT of the pouch 10. The bottom seal portion 14 is a portion where the front film 11a, the rear film 11b, and the bottom film 11c, which face each other in the depth direction D, are heat-sealed, and is located at the end of the lower side LO of the pouch 10. The top seal portion 12, the horizontal seal portion 13, and the bottom seal portion 14 heat-seal the film sheet 11 around the filling space 10s, thereby forming a substantially rectangular bag-shaped pouch 10 in which the filling space 10s is sealed.

Fig. 2 is a front view and a side view showing the plug 20 according to this embodiment. Fig. 2(a) is a front view of the plug 20. Fig. 2(b) is a side view of the plug 20.
FIG. 3 is a cross-sectional view of the upper seal portion 12 in which the plug 20 and the film sheet 11 are welded together.

The plug 20 comprises a main body 20a and a welded portion 22s. The main body 20a and the welded portion 22s are made of different resin materials, and the melting point of the resin forming the welded portion 22s is lower than the melting point of the resin forming the main body 20a. It is desirable that the melting point of the resin forming the welded portion 22s is at least 10°C lower than the melting point of the resin forming the main body 20a.

The main body 20a includes an opening 21, a connection 22, a flow path 23, and an extension 24. The main body 20a is formed by injection molding using a resin material. High density polyethylene (HDPE) or the like can be used as the material for the main body 20a. The material for the main body 20a is not limited to high density polyethylene (HDPE) and may be any material that has sufficient rigidity.

The mouth portion 21 is generally cylindrical and is disposed on the upper side UP of the main body portion 20a. Here, the central axis of the mouth portion 21 in the vertical direction V is defined as the central axis O. The mouth portion 21 has a helical screw portion 21a that screws into the cap 30.

As shown in FIG. 3, the connection part 22 has a cylindrical part 22a, a left extension part 22b, and a right extension part 22c. The cylindrical part 22a is the base of the connection part 22, and is substantially cylindrical with a central axis O as the central axis. The left extension part 22b is connected to the left side LT of the cylindrical part 22a, and has a shape that tapers from the right side RT toward the left side LT when viewed from the upper side UP. The right extension part 22c is connected to the right side RT of the cylindrical part 22a, and has a shape that tapers from the left side LT toward the right side RT when viewed from the upper side UP.

The connection part 22 is disposed on the lower side LO of the mouth part 21. The end of the lower side LO of the mouth part 21 is connected to the end of the upper side UP of the connection part 22. The inner circumferential surface of the mouth part 21 and the inner circumferential surface of the cylindrical part 22a are connected to form a flow path 23.

The flow path 23 is a cylindrical space that communicates with the mouth 21 and the connection part 22 and has a central axis O. The contents filled in the filling space 10s of the spouted pouch 100 are taken out to the outside from the end of the upper side UP of the mouth 21 via the flow path 23.

When viewed from the front side FR and the rear side RR, the extension 24 has a generally U-shaped shape with the opening of the U facing the upper side UP. The upper side UP end of the extension 24 is connected to the lower side LO end of the connection part 22. The extension 24 has a constant thickness in the depth direction D. Therefore, when the user sucks out the contents filled in the filling space 10s, the extension 24 restricts the movement of the film sheet 11 in the depth direction D, securing space in the depth direction D of the filling space 10s and preventing the end of the lower side LO of the flow path 23 from being blocked by the film sheet 11.

As shown in FIG. 3, the welded portion 22s is formed on the outer circumferential surface (surface) of the connection portion 22, and is the portion that is heat sealed to the film sheet 11 in the spouted pouch 100. Low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE) can be used as the material for the welded portion 22s.

The melting point of the resin forming the welded portion 22s is preferably a temperature lower than the melting point of the resin forming the film sheet 11. In addition, the upper limit of the melting point of the resin forming the welded portion 22s is more preferably a temperature 5°C lower than the melting point of the resin forming the film sheet 11, and the lower limit is more preferably a temperature 15°C lower than the melting point of the resin forming the film sheet 11.

The welded portion 22s includes a welded rib 22d. The welded rib 22d is formed on the surface of the welded portion 22s and has a convex shape that protrudes in the depth direction D. In this embodiment, three welded ribs 22d are arranged on each of the front side FR and the rear side RR.

The welding portion 22s and the welding rib 22d are the portions that melt and adhere to the film sheet 11 when the spout 20 and the film sheet 11 are heat-sealed. By providing the welding rib 22d to the welding portion 22s, the spout 20 can secure a sufficient amount of resin to melt when the spout 20 and the film sheet 11 are heat-sealed. In addition, in the heat-sealed spout 20 and film sheet 11, the welding rib 22d catches the film sheet 11 in the vertical direction V, and peeling of the spout 20 and the film sheet 11 in the vertical direction V can be suppressed. If the spout 20 and the film sheet 11 can be sufficiently heat-sealed without the welding rib 22d, the welding portion 22s does not need to include the welding rib 22d.

The cap 30 is a lid that prevents the contents of the spouted pouch 100 from leaking to the outside. The cap 30 is substantially cylindrical with the upper side UP blocked, and a groove on the inner peripheral surface is screwed with the screw portion 21a of the spout 20 to connect to the spout 20. The contents of the spouted pouch 100 are sealed by covering the spout 20 with the cap 30. A user can remove the contents filled in the filling space 10s to the outside by releasing the screwing between the spout 20 and the cap 30 and opening the spouted pouch 100. For example, if the contents filled in the filling space 10s are beverages, the user can remove the cap 30 from the spout 20, open it, and drink the beverage from the opening on the upper side UP of the spout 20 via the flow path 23.

Next, an example of a method for manufacturing the spouted pouch 100 will be described.

Figure 4 is a flow chart showing an example of a method for manufacturing a spouted pouch 100. Figure 5 is a schematic diagram showing an example of a method for manufacturing a spouted pouch 100.

First, step S1 (plug supply process) is carried out. In step S1, the plug 20 is first formed. The plug 20 has a main body portion 20a and a welded portion 22s formed from different resins. Therefore, the plug 20 is formed by two-color molding.

Here, two-color molding is an injection molding method in which a molded product is formed using two or more types of material. In the molding process of the plug 20, a resin with sufficient rigidity, such as high density polyethylene (HDPE), is injected into a mold to mold the main body 20a. Next, a resin with a lower melting point than the melting point of the resin forming the main body 20a, such as low density polyethylene (LDPE) or linear low density polyethylene (LLDPE), is injected into the mold to mold the welded portion 22s. By using two-color molding, the plug 20 can be molded using two or more resins with different melting points.

The formed spout 20 is supplied to a manufacturing line for spouted pouches 100. After the spout 20 is supplied to the manufacturing line for spouted pouches 100, a mold is brought into contact with the welded portion 22s of the spout 20 to heat (preheat). In step S1, for example, a mold is pressed against the welded portion 22s of the spout 20, and the spout 20 is heated at 150°C for 0.18 seconds. Here, the manufacturing line refers to a manufacturing process in which each component part of the spouted pouch 100 is sent through each process in order at a set time for each process, and is subjected to processing such as heat sealing.

Next, step S2 (film supply process) is carried out. In step S2, the film sheet 11 is supplied to the production line. The film sheet 11 supplied to the production line in step S2 has the side seal portion 13 and bottom seal portion 14 heat sealed, and has a bag shape that is open on the upper side UP. The film sheet 11 may be printed with a product name or logo in advance.

In step S2, a temporary heat sealing process is carried out to determine the positions of the film sheet 11 and the stopper 20 in preparation for the heat sealing process described below. In the temporary heat sealing process, the stopper 20 is inserted into the opening on the upper side UP of the supplied bag-shaped film sheet 11, and the welded portion 22s of the stopper 20 is sandwiched between the film sheets 11 facing each other in the depth direction D at the end of the upper side UP of the film sheet 11. The film sheet 11 and the welded portion 22s are heated and pressurized from the front side FR and rear side RR of the film sheet 11 with the stopper 20 sandwiched therebetween, melting and bonding the film sheet 11 and the welded portion 22s together. Here, the temporary heat sealing step only needs to determine the position of the film sheet 11 relative to the spout 20. For example, in the upper seal section 12, a metal mold is pressed against only a portion of the film sheet 11 and the welded portion 22s, and the film sheet 11 and only a portion of the welded portion 22s are heated at 180° for 0.8 seconds to melt and bond the film sheet 11 and only a portion of the welded portion 22s, thereby determining the position of the film sheet 11 relative to the spout 20. Note that if positioning by the temporary heat sealing step is not necessary, the process may proceed to step S3 without performing the temporary heat sealing step.

Next, step S3 (heat sealing process) is performed. In step S3, the spout 20 and film sheet 11 supplied to the production line in steps S1 and S2 are heat sealed and connected. The film sheet 11 and the welding portion 22s are heated and pressurized from the front side FR and rear side RR of the film sheet 11 to melt and bond the film sheet 11 and the welding portion 22s. In step S3, the film sheet 11 and the welding portion 22s are heat sealed to form the upper seal portion 12 of the pouch 10. Note that at this time, the heat sealing process may be performed in multiple steps, and a cooling process may be provided after the heat sealing to cool the heat sealed portion.

For example, in step S3, a heating process at 155°C for 0.8 seconds is performed three times. By dividing the heat sealing performed in step S3 into three processes, a first heat sealing process, a second heat sealing process, and a third heat sealing process, the time required for step S3 is prevented from being longer than the other processes, and the impact on the time available for manufacturing the spouted pouch 100 (takt time) can be minimized.

In addition, in the cooling process after heat sealing, for example, a mold (cooling seal plate) is brought into contact with the portion (heat seal portion) where the film sheet 11 and the welded portion 22s are heat sealed to cool the heat seal portion. The cooling seal plate may be at room temperature (normal temperature), or may be one in which chilled water is circulated inside to keep the temperature below room temperature.

The heat sealing to form the horizontal seal portion 13 and the bottom seal portion 14 may be performed in step 3. For example, a sheet-like film sheet 11 that has not been heat-sealed may be supplied to the production line, and the horizontal seal portion 13 and the bottom seal portion 14 may be heat-sealed when the film sheet 11 and the spout 20 are heat-sealed in step S3.

When the spout 20 and the film sheet 11 are heat-sealed, the welded portion 22s melts and adheres to the film sheet 11, and the spout 20 and the film sheet 11 are bonded together. If the welded portion 22s has a welded rib 22d, the welded rib 22d also melts and adheres to the film sheet 11 together with the welded portion 22s. Here, the melting point of the resin forming the welded portion 22s is lower than the melting point of the resin forming the main body portion 20a. The melting point of the resin forming the welded portion 22s is a temperature below the melting point of the resin forming the film sheet 11. In addition, in step S3, the temperature to which the welded portion 22s and the film sheet 11 are heated is preferably a temperature below the melting point of the resin forming the film sheet 11.

The plug 20 is molded by two-color molding using resins with different melting points. For example, the main body 20a is made of high density polyethylene (HDPE) with a melting point of 131°C. The welded portion 22s is made of linear low density polyethylene (LLDPE) with a melting point of 113°C. As the majority of the plug 20 is made of high density polyethylene (HDPE), the plug 20 has sufficient rigidity.

The film sheet 11 is made of linear low density polyethylene (LLDPE) with a melting point of 113°C. Since the melting point of the resin forming the welded portion 22s is the same as the melting point of the resin forming the film sheet 11, when the film sheet 11 and the spout 20 are heat-sealed in step S3, they can be heated at a temperature close to the melting point of the resin forming the film sheet 11. As a result, excessive heat is not applied to the film sheet 11, and wrinkles do not occur in the film sheet 11. Therefore, heat sealing can be performed without creating a gap between the spout 20 and the film sheet 11, and the contents filled in the filling space 10s in the spouted pouch 100 can be prevented from leaking to the outside.

If there is a risk of wrinkles occurring in the film sheet 11 due to heating during heat sealing, it is necessary to use a laminated film with high rigidity by laminating nylon, aluminum, or the like for the film sheet 11 in order to prevent wrinkles in the film sheet 11. However, by reducing the temperature difference between the melting point of the resin forming the welded portion 22s and the melting point of the resin forming the film sheet 11, the spout 20 and the film sheet 11 can be sufficiently heat-sealed even when a film sheet 11 made of a single material such as polyethylene resin is used, so the spout-equipped pouch 100 has excellent recyclability. In addition, the main body 20a is formed of a resin with sufficient rigidity such as high-density polyethylene (HDPE), so the spout 20 has sufficient rigidity.

After heat sealing the welded portion 22s and the film sheet 11, the welded portion 22s and the film sheet 11 are inspected to see if they are sufficiently bonded together, and then the process moves to the next step.

Next, step S4 (filling process) is carried out. In step S4, the contents are filled into the filling space 10s of the pouch 10 from the opening on the upper side UP of the mouth portion 21 via the flow path 23. After the contents are filled into the filling space 10s, the pouch 10 and the mouth plug 20 are washed and dried, and the process proceeds to the next step.

Next, step S5 (lid closing process) is carried out. In step S5, the opening on the upper side UP of the mouth portion 21 is closed with the cap 30 to seal the spouted pouch 100. Next, an inspection is carried out to check whether the cap 30 is properly closed, and the manufacturing process of the spouted pouch 100 is completed.

According to the spout 20 and spout-equipped pouch 100 of this embodiment, the melting point of the resin forming the welded portion 22s is lower than the melting point of the resin forming the main body portion 20a. In addition, the melting point of the resin forming the welded portion 22s is a temperature lower than the melting point of the resin forming the film sheet 11. Therefore, the spout 20 and the film sheet 11 can be heat-sealed without wrinkles occurring in the film sheet 11. As a result, it is possible to provide a spout 20 that can suppress the occurrence of a gap between the spout 20 and the film sheet 11 when the spout 20 and the film sheet 11 are welded, a spout-equipped pouch 100, and a method for manufacturing the spout-equipped pouch 100. In addition, since the spout 20 and the film sheet 11 can be sufficiently heat-sealed even with a film sheet 11 made of a single material such as polyethylene resin, a spout-equipped pouch 100 with excellent recyclability can be provided.

Although one embodiment of the present invention has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design modifications and the like that do not deviate from the gist of the present invention are also included. In addition, the components shown in the above-mentioned embodiment and the modified examples shown below can be configured in appropriate combinations.

(Variation 1)
In the above embodiment, the plug 20 is molded by two-color molding, but the molding method of the plug 20 is not limited to this. The plug may be molded by insert molding.

When molding a stopper by insert molding, first prepare a film for insert molding made of low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE), etc.

Next, in the mold used for insert molding, the film for insert molding is placed at the position where the welded part will be formed. A resin with sufficient rigidity, such as high density polyethylene (HDPE), is injected into the mold with the film for insert molding placed in it to mold the main body.

In plugs molded by insert molding, the welded part is formed from the insert molding film. As a result, the main body and the welded part are made from different resins.

By forming the insert molding film from a resin with a melting point lower than that of the resin forming the main body, the melting point of the resin forming the welded portion is lower than that of the resin forming the main body. In this case, the melting point of the resin forming the welded portion is a temperature lower than the melting point of the resin forming the film sheet 11.

Therefore, when heat sealing the film sheet 11 and the stopper, the film sheet 11 can be heated to a temperature close to the melting point of the resin that forms the film sheet 11. As a result, excessive heat is not applied to the film sheet 11, wrinkles do not occur in the film sheet 11, and the occurrence of gaps between the stopper and the film sheet 11 can be suppressed. In addition, since the stopper and the film sheet 11 can be sufficiently heat sealed even with a film sheet 11 made of a single material such as polyethylene resin, a pouch with a stopper that has excellent recyclability can be provided.

100 Pouch with spout 11 Film sheet 20 Spout 20a Body 21 Mouth 22s Welding section S1 Spout supply step S3 Heat sealing step

Claims (11)

A substantially cylindrical main body portion;
A welding portion disposed on an outer circumferential surface of the main body portion;
Equipped with
The melting point of the resin forming the welded portion is lower than the melting point of the resin forming the main body portion.
Mouth plug. The melting point of the resin forming the welded portion is at least 10° C. lower than the melting point of the resin forming the main body portion.
The plug according to claim 1. the body portion comprises high density polyethylene;
The welded portion includes linear low density polyethylene or low density polyethylene,
The plug according to claim 2. A plug according to any one of claims 1 to 3,
A film sheet heat-sealed into a bag shape;
Equipped with
The welded portion of the plug and the film sheet are heat-sealed.
Pouch with stopper. The film sheet is made of a single material.
5. The spouted pouch according to claim 4. The melting point of the resin forming the welding portion is a temperature lower than the melting point of the resin forming the film sheet.
6. The spouted pouch according to claim 5. the upper limit of the melting point of the resin forming the welded portion is a temperature that is 5° C. lower than the melting point of the resin forming the film sheet;
The lower limit of the melting point of the resin forming the welded portion is a temperature 15° C. lower than the melting point of the resin forming the film sheet.
7. The spouted pouch according to claim 6. The film sheet comprises linear low density polyethylene or low density polyethylene,
8. The spouted pouch according to claim 7. a plug supplying step of forming a plug having a main body and a welding part formed of a resin having a melting point lower than the melting point of the resin forming the main body;
a heat sealing step of welding the welding portion and a bag-shaped film sheet;
Equipped with
A method for manufacturing a pouch with a spout. The film sheet is made of a single material.
A method for producing the spouted pouch according to claim 9. the melting point of the resin forming the welding portion is equal to or lower than the melting point of the resin forming the film sheet;
The temperature at which the welding portion and the film sheet are heated in the heat sealing step is equal to or lower than the melting point of the resin forming the film sheet.
A method for producing the spouted pouch according to claim 10.

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