High-temperature filling method
By covering the container port with a heated shrink film or a top cylindrical cup in a double-layer container filled with high temperature, the problem of cooling water entering is solved, and the container is sealed and hygienic.
Patent Information
- Application Number
- JP2023122756
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-07-27
- Publication Date
- 2025-02-06
AI Technical Summary
When filling a double-layer container at high temperatures, cooling water may enter through the air inlet between the outer and inner layers, causing the container to deform and contaminate.
Use a heated shrink film or a top cylindrical cup as the cover, cover the container port after filling at high temperature, and shrink it by heating to close the container port to prevent cooling water from entering.
Effectively prevent cooling water from entering between the outer and inner layers of the double-layer container, avoid container deformation and contamination, and ensure the sealing and hygiene of the container.
Smart Images
Figure 2025018764000001_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a high-temperature filling method for filling a double-walled synthetic resin container with a liquid at a high temperature. [Background technology]
[0002] Conventionally, as a container for containing food contents such as seasonings (soy sauce or vinegar), a double container made of synthetic resin has been known which has a bottle-shaped outer layer with a mouth, a body and a bottom, an inner layer which has a storage space for the contents and is contained in the outer layer and can be freely reduced in volume and deformed, and an outside air inlet port provided in the mouth for introducing outside air between the outer layer and the inner layer (see, for example, Patent Document 1).
[0003] After the double container having the above configuration is filled with the contents, a cap is attached to the mouth portion to close the mouth portion. For example, a cap having a configuration including a discharge port for discharging the contents, a check valve for the contents for opening and closing the discharge port, and a check valve for air provided between the outside air inlet and the air intake port is used. By attaching such a cap to the mouth portion, the double container can suppress the introduction of outside air into the inside of the inner layer by reducing and deforming only the inner layer without changing the shape of the outer layer as the contents are discharged to the outside through the mouth portion. This makes it possible to suppress deterioration and alteration of the contents contained in the container due to oxidation. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] JP 2020-23352 A Summary of the Invention [Problem to be solved by the invention]
[0005] A hot filling method is known as a method for filling a container with a content that requires sterilization. The hot filling method generally includes a filling step in which the content is heated to a high temperature of 65°C or higher for sterilization and filled into a container, a capping step in which a cap is attached to the mouth of the container after the filling step to close the mouth of the container, and a cooling step in which a shower of cold water is sprayed on the container to cool it down in order to prevent thermal deformation of the mouth of the container, etc., after the capping step.
[0006] However, when the high-temperature filling method is applied to a double-layered container made of synthetic resin as described above, there is a problem in that when the container is showered with cooling water in the cooling process, the inner layer shrinks as the contents are cooled, creating negative pressure between the outer layer and the inner layer, and there is a risk that cooling water will enter between the outer layer and the inner layer through the outside air inlet. As a result, high-temperature filling into a double-layered container cannot be carried out.
[0007] The present invention has been made in consideration of such problems, and its object is to provide a high-temperature filling method that can prevent cooling water from entering between the outer layer and the inner layer during the cooling process. [Means for solving the problem]
[0008] The high-temperature filling method of the present invention is a method for hot filling contents into a double container made of synthetic resin having a bottle-shaped outer layer with a mouth, a body, and a bottom, an inner layer having a storage space for the contents and which is housed in the outer layer and can be freely reduced in volume and deformed, and an outside air inlet provided in the mouth for introducing outside air between the outer layer and the inner layer, and is characterized by having a filling step of filling the double container with contents heated to 65°C or higher, a capping step of fitting a cap to the mouth to close the mouth after the filling step, a covering step of covering the cap with a cover after the capping step, and a cooling step of pouring cooling water over the double container to cool it after the covering step.
[0009] In the high-temperature filling method of the present invention, in the above-mentioned configuration, it is preferable that the cover is a shrink film, and in the covering process, the shrink film arranged on the outside of the cap is heated and contracted to cover the cap with the shrink film.
[0010] In the hot filling method of the present invention having the above-mentioned configuration, it is preferable that the cover is a cylindrical cup with a top, and that in the covering step, the cup is placed over the mouth portion from above.
[0011] In the above-mentioned configuration, the hot filling method of the present invention preferably further comprises a removing step of removing the cover from the double container after the cooling step. Effect of the Invention
[0012] According to the present invention, it is possible to provide a hot filling method capable of preventing the intrusion of cooling water between the outer layer body and the inner layer body during the cooling step. [Brief description of the drawings]
[0013] [Figure 1] FIG. 2 is a partially cutaway front view of a double container used in a hot filling method according to one embodiment of the present invention, with a cap attached. [Diagram 2] 2 is an enlarged cross-sectional view of the mouth of the double container shown in FIG. 1 to which a cap is attached. [Diagram 3] FIG. 2 is a schematic cross-sectional view of an inner preform and an outer preform. [Figure 4] FIG. 2 is a schematic cross-sectional view of a preform assembly. [Diagram 5] FIG. 10 is an explanatory diagram showing a state in which the contents are filled into the double container in the filling process. [Figure 6] FIG. 11 is a front view of the double container after the capping process is completed. [Figure 7] 11 is an explanatory diagram showing a state in which a shrink film is placed on the outside of a cap in a covering process. FIG. [Figure 8]FIG. 11 is a front view of the double container after the covering process is completed. [Figure 9] FIG. 11 is an explanatory diagram showing a state in which cooling water is poured into the double container in the cooling process. [Figure 10] 13 is an explanatory view showing a state in which the cap is covered with the cover in a covering step according to a modified example. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] The present invention will now be described in more detail with reference to the drawings.
[0015] The hot filling method according to one embodiment of the present invention is a method for hot filling a double-walled container made of synthetic resin with a content.
[0016] As shown in Figures 1 and 2, the double container 1 used in the high-temperature filling method of this embodiment is made of synthetic resin and is also called a delaminated container (delaminated container), and has a double structure having an outer layer 10 and an inner layer 20.
[0017] In this specification, claims and drawings, the up-down direction refers to the up-down direction when the double container 1 is in an upright position as shown in FIG.
[0018] The outer layer 10 is a part that constitutes the outer shell of the double container 1, and has a bottle shape with a mouth 11, a body 12 and a bottom 13.
[0019] The mouth portion 11 is cylindrical with its center on the axis O, and has an external thread 11a formed integrally on its outer circumferential surface. A cap 30 can be attached to the mouth portion 11 by threadedly engaging with the external thread 11a.
[0020] The mouth 11 may have an annular projection instead of the male thread 11a, and the cap 30 may be attached by engaging with the projection in an undercut shape by tapping. In this case, the mouth 11 is not limited to a cylindrical shape, and may be, for example, a square or elliptical cylindrical shape as long as it is cylindrical.
[0021] The body 12 has a shoulder-like portion 12a that is integral with the lower end of the mouth 11 and gradually expands in diameter downward to project radially outward from the mouth 11, and a substantially cylindrical body main portion 12b that is integral with the lower end of the shoulder-like portion 12a and has a slightly narrowed portion. The body main portion 12b forms a squeeze region that can be squeezable (pressed).
[0022] The bottom 13 is integrally connected to the lower end of the body 12 and closes the lower end of the body 12. The bottom 13 has an annular outer peripheral edge 13a and a recess 13b that is provided inside the outer peripheral edge 13a and recessed upward in a semispherical shape, and the double container 1 can be placed in an upright position by grounding the outer peripheral edge 13a.
[0023] The inner layer 20 is formed in a thin bag shape with a thinner wall than the outer layer 10, and is freely shrinkable and deformable, and is contained in the outer layer 10 in a peelable laminated state over the entire inner surface of the body 12 and bottom 13 of the outer layer 10. The inside of the inner layer 20 forms a storage space S for the contents (content liquid), and can store foods that require sterilization, such as seasonings (soy sauce and vinegar), as the contents. The inner layer 20 shrinks and deforms as the contents are discharged to the outside through the opening 11, and can be peeled off from the body 12 and bottom 13 of the outer layer 10.
[0024] An outside air inlet 14 is provided at the mouth 11 of the outer layer body 10. The outside air inlet 14 is a through hole that penetrates the mouth 11 in a radial direction perpendicular to the axis O, and allows outside air to be introduced between the outer layer body 10 and the inner layer body 20. In this embodiment, the mouth 11 is provided with a pair of outside air inlets 14 on either side of the axis O, but the number, arrangement, etc. thereof can be changed in various ways.
[0025] The cap 30 to be attached to the mouth 11 may have, for example, a configuration including a cap body 32 having a topped cylindrical shape and a discharge port 31, a plug 34 having an outlet 33 and attached to the inside of the cap body 32, a lid 35 for opening and closing the discharge port 31, a check valve 36 for the contents for opening and closing the outlet 33, a check valve 38 for air provided between an intake port 37 provided in the cap body 32 and the outside air introduction port 14, and a ball valve 39 for sucking back provided in the inside plug 34. In this case, the inner peripheral surface of the lower end of the cap body 32 abuts over the entire circumference against an annular protrusion 11b provided on the lower end side of the mouth 11, isolating the flow path for outside air between the intake port 37 and the outside air introduction port 14 from the outside.
[0026] By fitting such a cap 30 to the mouth 11, the double container 1 can discharge the contents from the discharge port 31 of the cap 30 by squeezing the body part 12b, and when the squeeze of the body part 12b is released, the discharge port 31 is closed by the check valve 36, and the check valve 38 is opened by the negative pressure generated between the outer layer 10 and the inner layer 20, and outside air is introduced from the intake port 37 through the outside air inlet 14 into the gap between the outer layer 10 and the inner layer 20, so that the outer layer 10 returns to its original shape while only the inner layer 20 is reduced in volume, thereby suppressing the inflow of outside air into the storage space S. This makes it possible to suppress deterioration and alteration of the contents stored in the storage space S due to oxidation.
[0027] The cap 30 attached to the mouth portion 11 is not limited to the above-mentioned configuration, and caps of various configurations can be used.
[0028] The double container 1 according to this embodiment can be formed as a peelable laminate container by, for example, separately manufacturing an inner preform 2 and an outer preform 3 as shown in Fig. 3 by injection molding of a synthetic resin material, combining them to manufacture a preform assembly 4 as shown in Fig. 4, and biaxially stretching and blow molding the preform assembly 4. In Figs. 3 and 4, the parts corresponding to the mouth parts 11 of the inner preform 2 to the outer preform 3 are shown in a simplified schematic form, but the parts corresponding to the mouth parts 11 of the inner preform 2 to the outer preform 3 are not biaxially stretched and blow molded, and therefore have a shape corresponding to the mouth parts 11.
[0029] The double container 1 is not limited to those manufactured by the above-mentioned manufacturing method, but may be formed, for example, by extrusion blow molding (EBM), in which a laminated parison formed by radially stacking a synthetic resin material forming the outer layer 10 and a synthetic resin material forming the inner layer 20 is sandwiched between a mold and air is blown into it to form a container.
[0030] The double container 1 according to this embodiment is a so-called PET bottle in which the outer layer 10 and the inner layer 20 are both made of polyethylene terephthalate resin (PET).
[0031] In addition, the outer layer body 10 and the inner layer body 20 of the double container 1 may be formed of a synthetic resin material other than polyethylene terephthalate resin. In this case, the outer layer body 10 and the inner layer body 20 may be formed of different types of synthetic resin materials.
[0032] Next, a hot filling method according to this embodiment using the double container 1 having the above-mentioned configuration will be described.
[0033] The hot filling method according to this embodiment includes a filling step, a capping step, a covering step, and a cooling step.
[0034] 5, in the filling process, the double container 1 is filled with contents heated to 65°C or higher. More specifically, the double container 1 without the cap 30 is placed in an upright position, and contents 42 heated to 65°C or higher are filled from the mouth 11 into the inside of the double container 1, i.e., the storage space S, through a filling nozzle 41 of a filling machine 40 placed above the double container 1.
[0035] The temperature of the contents 42 filled into the double container 1 in the filling step can be set appropriately depending on the contents 42 as long as it is 65° C. or higher. In this embodiment, the temperature of the contents 42 filled into the double container 1 in the filling step is 85° C. The upper limit of the temperature of the contents 42 filled into the double container 1 in the filling step is not particularly limited, but is, for example, 95° C. or lower.
[0036] After the filling step is completed, the capping step is performed. As shown in Fig. 6, in the capping step, the cap 30 is attached to the mouth 11 of the double container 1 filled with the content 42, and the mouth 11 is closed with the cap 30. The capping step may be performed automatically using a device such as a capper.
[0037] After the capping process is completed, the covering process is performed. As shown in Figures 7 and 8, in the covering process, the cap 30 attached to the mouth 11 of the double container 1 filled with the content 42 is covered with a cover 50. The cover 50 is made of a waterproof material.
[0038] In this embodiment, the cover 50 is a shrink film 51. The shrink film 51 is also called a shrink label, and is made of, for example, polystyrene (PS) resin, and has the property of shrinking when heated. In this embodiment, the shrink film 51 is formed in a cylindrical shape whose vertical length is greater than the vertical dimension of the cap 30 and whose diameter is greater than that of the cap 30.
[0039] As shown in Fig. 7, in the covering step, the cylindrical shrink film 51 is placed on the outside of the cap 30. Then, as shown in Fig. 8, the shrink film 51 is heated and shrunk in this state by blowing hot air thereon, and the shrink film 51 is brought into close contact with the outer peripheral surface of the cap 30 and the outer peripheral surface of the double container 1, thereby covering and sealing the cap 30. At this time, it is preferable that the abutting portion between the lower end of the cap body 32 of the cap 30 and the protrusion 11b on the lower end side of the mouth portion 11 is covered with the shrink film 51, and that the entire cap 30 is covered with the shrink film 51 through the opening 51a provided on the upper side, leaving a part of the upper end surface of the lid 35 of the cap 30.
[0040] After the covering step is completed, the cooling step is performed. As shown in Fig. 9, in the cooling step, cooling water 60 is poured onto the double container 1 in which the cap 30 is covered with the cover 50, and the double container 1 filled with the contents 42 is cooled to a temperature of 65°C or higher by the cooling water 60. In the cooling step, it is preferable to pour the cooling water 60 onto the double container 1 in the form of a shower. By cooling the double container 1 filled with the contents 42 at a temperature of 65°C or higher using the cooling water 60 in the cooling step, deformation of the mouth portion 11 due to the heat of the contents 42 can be suppressed.
[0041] After the covering step is completed, the double container 1 may be placed in a sideways position for a predetermined period of time, and then placed in an upright position for a predetermined period of time, after which the cooling step may be carried out.
[0042] As described above, in the hot filling method of this embodiment, a filling step is performed in which the double container 1 is filled with the contents 42 heated to 65°C or higher, and after the filling step, a capping step is performed in which the cap 30 for closing the mouth 11 is attached to the mouth 11, and then a covering step is performed in which the cap 30 is covered with the cover 50 before a cooling step is performed in which cooling water 60 is poured onto the double container 1 to cool it. That is, when cooling water 60 is poured onto the double container 1 in the cooling step, the cap 30 is covered with the cover 50. As a result, in the cooling process, cooling water 60 is poured onto the double container 1 to cool the contents 42, and as a result, the inner layer 20 contracts, creating a negative pressure between the outer layer 10 and the inner layer 20. Even if a suction force is generated at the outside air inlet 14 that tries to draw the cooling water 60 into between the outer layer 10 and the inner layer 20, since the cap 30 attached to the mouth 11 is covered by the cover 50, the cooling water 60 can be prevented from entering between the outer layer 10 and the inner layer 20 through the outside air inlet 14 provided in the mouth 11.
[0043] In particular, in this embodiment, since the double container 1 is a peelable laminated container, if cooling water 60 penetrates between the outer layer 10 and the inner layer 20, there is a risk that the penetrated cooling water 60 will stagnate between the outer layer 10 and the inner layer 20, causing hygiene problems. However, as described above, according to the high-temperature filling method of this embodiment, it is possible to prevent the cooling water 60 from penetrating between the outer layer 10 and the inner layer 20, so that no hygiene problems will arise.
[0044] In this embodiment, the cover 50 is a shrink film 51, and in the covering process, the shrink film 51 arranged on the outside of the cap 30 is heated and shrunk to cover the cap 30 with the shrink film 51, so that the cooling water 60 can be more reliably prevented from entering between the outer layer body 10 and the inner layer body 20 through the outside air inlet 14 provided in the mouth portion 11. More specifically, the butted portion between the cap body 32 and the lid 35 is reliably covered with the shrink film 51 to prevent the cooling water 60 from being sucked into the outside air inlet 14 through the intake port 37 provided in the cap body 32, and the abutting portion between the lower end of the cap body 32 and the protrusion 11b on the lower end side of the mouth portion 11 is reliably sealed with the shrink film 51 to prevent the cooling water 60 from being sucked into the outside air inlet 14 through the abutting portion.
[0045] In the cooling step of the hot filling method of this embodiment, for example, the temperature of the cooling water 60 may be gradually lowered to 60° C., 40° C., and 30° C. while it is poured onto the double container 1. This reduces the negative pressure that occurs between the outer layer body 10 and the inner layer body 20 due to the shrinkage of the inner layer body 20 as the content 42 is cooled, and makes it possible to more effectively prevent the cooling water 60 from entering between the outer layer body 10 and the inner layer body 20 through the outside air inlet 14.
[0046] 10, a cylindrical cup 52 with a top may be used as the cover 50 in the covering step. The cup 52 may be made of a synthetic resin material, but the material may be changed in various ways.
[0047] In this embodiment, the cup 52 is cylindrical with a top, having a cylindrical peripheral wall 52a with a diameter larger than that of the cap 30 and smaller than the maximum diameter portion of the shoulder portion 12a of the double container 1, and a top wall 52b that closes the upper end of the peripheral wall 52a.
[0048] In this case, in the covering step, the cap 30 can be covered with the cup 52, which is the cover 50, by covering the mouth portion 11 from above. At this time, it is preferable that the lower end of the peripheral wall 52a of the cup 52 abuts against the shoulder portion 12a of the double container 1 over the entire circumference.
[0049] Even when a topped cylindrical cup 52 is used as the cover 50, in the cooling process, cooling water 60 is poured onto the double container 1 to cool the contents 42, causing the inner layer 20 to contract and creating a negative pressure between the outer layer 10 and the inner layer 20, and a suction force is generated at the outside air inlet 14 that tries to draw the cooling water 60 into between the outer layer 10 and the inner layer 20.However, since the cap 30 attached to the mouth 11 is covered by the cup 52, the cooling water 60 can be prevented from entering between the outer layer 10 and the inner layer 20 through the outside air inlet 14 provided in the mouth 11.
[0050] When a cylindrical cup 52 with a top is used as the cover 50, a protrusion 52c may be provided on the underside of the top wall 52b so that the protrusion 52c abuts on the top surface of the lid 35 of the cap 30 when the cap 30 is covered with the cup 52. This makes it difficult for the cup 52 to shift position relative to the double container 1 even if the cooling water 60 hits the cup 52 during the cooling process, and more reliably prevents the cooling water 60 from entering between the outer layer body 10 and the inner layer body 20 through the outside air inlet 14.
[0051] When a cylindrical cup 52 with a top is used as the cover 50, a flange 52d may be provided at the lower end of the peripheral wall 52a. This allows the flange 52d to prevent the cooling water 60 from entering the cap 30 side through the gap between the lower end of the peripheral wall 52a of the cup 52 and the shoulder-like portion 12a, and more reliably prevents the cooling water 60 from entering between the outer layer body 10 and the inner layer body 20 through the outside air inlet 14.
[0052] The hot filling method of this embodiment may be configured to include a removal step of removing the cover 50 from the double container 1 after the cooling step. In particular, when a topped cylindrical cup 52 is used as the cover 50, the cup 52 may be removed from the double container 1 after the cooling step, and then the double container 1 may be distributed as a product. This simplifies the configuration of the double container 1 that is distributed as a product.
[0053] When a shrink film 51 is used as the cover 50, the double container 1 may be distributed as a product without removing the shrink film 51 after the cooling process. In this case, the shrink film 51 can indicate that the double container 1 is unopened.
[0054] Incidentally, even when the shrink film 51 is used as the cover 50, the shrink film 51 may be removed from the double container 1 after the cooling step, and then the product may be distributed.
[0055] The present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit and scope of the present invention.
[0056] For example, in the above embodiment, the double container 1 is configured as a peelable laminated container in which the inner layer 20 is peelably laminated to the inner surface of the outer layer 10, but this is not limited to this, and the double container 1 may also be configured in such a way that an inner layer formed separately from the outer layer is incorporated inside the outer layer.
[0057] In addition, in the above embodiment, the outside air inlet 14 is provided as a through hole in the mouth portion 11 of the outer layer 10, but this is not limited to this, and as long as it is provided in the mouth portion 11, its form can be modified in various ways, such as being provided as a gap between the outer layer 10 and the inner layer 20 that opens at the upper end of the mouth portion 11.
[0058] Furthermore, in the above embodiment, a shrink film 51 or a topped cylindrical cup 52 is used as the cover 50 in the covering process, but this is not limited to this, and various shapes and configurations can be used as long as they can cover the cap 30 and prevent the cooling water 60 from splashing on the cap 30 in the cooling process. [Explanation of symbols]
[0059] 1 double container 2. Inner preform 3 Outer preform 4 Preform Assembly 10 Outer body 11 Mouth 11a Male thread 11b Protrusion 12 Torso 12a shoulder 12b Body part 13 Bottom 13a Outer periphery 13b Recess 14 Fresh air intake 20 Inner layer 30 Cap 31 Discharge port 32 Cap body 33 Outlet 34 Inner stopper 35 Lid 36 Check valve 37 Air Intake 38 Check valve 39 Ball valve 40 Filling machine 41 Filling Nozzle 42 Contents 50 Cover 51 Shrink Film 52 cups 52a Peripheral wall 52b Top wall 52c Convex 52d flange 60 Cooling water O axis S Storage space
Claims
1. a bottle-shaped outer layer body having a mouth, a body, and a bottom; an inner layer body having a storage space for contents and capable of being freely reduced in volume and deformed and accommodated in the outer layer body; A method for hot filling a synthetic resin double-layered container having an outside air inlet provided at the mouth for introducing outside air between the outer layer and the inner layer, comprising the steps of: A filling step of filling the double container with a content heated to 65°C or higher; a capping step of attaching a cap to the mouth portion after the filling step, the cap closing the mouth portion; a covering step of covering the cap with a cover after the capping step; A hot filling method comprising the steps of: after the covering step, pouring cooling water over the double container to cool it;
2. The cover is a shrink film, 2. The hot filling method according to claim 1, wherein in the covering step, the shrink film arranged on the outside of the cap is heated and shrunk to cover the cap with the shrink film.
3. The cover is a cylindrical cup having a top, The hot filling method according to claim 1 , wherein in the covering step, the cup is placed over the mouth portion from above.
4. The hot-fill method according to any one of claims 1 to 3, further comprising a removing step of removing the cover from the double container after the cooling step.
Citation Information
Patent Citations
Double container
JP2020023352A