Resin molded container and method for manufacturing resin molded container

Abstract

To provide a resin mold container that is excellent in sealing property before use and can be attached to and detached from a tray body in a lid body even after opened and also can provide a stable attachment and detachment function between the lid body and the tray body, and a manufacturing method of the resin mold container.SOLUTION: A resin mold container has a lid body edge part 30 where a convex part 31 that protrudes in the direction of a ring-like edge part 20 is formed. In the ring-like edge part 20, a break line 23 that separates into an inner periphery side end part 21 and an outer periphery side end part 22. In the position where the convex part 31 is formed on the break line 23, the radial width of the inner periphery side end part 21 is made narrower than in the position where the convex part 31 is not formed.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a resin molded container in which a tray body capable of accommodating contents such as food and a lid body edge that is part of a lid covering a tray opening are integrally molded, a lid opening formed by the lid body edge is covered with a top film, and the tray body and the lid body are separated and used, and a method for manufacturing this resin molded container.

Background Art

[0002] Patent Document 1 discloses a resin molded container in which a tray having a tray opening formed therein and a lid body edge formed by rising up on the outer periphery of the tray opening are integrally molded via a break line, an opening formed by the lid body edge is covered with a film, and the tray body and the lid body are formed by separating along the break line. An inner ridge is formed on the lid body edge disclosed in Patent Document 1. After separating the tray body and the lid body by a break line, the lid body can be attached (clamped) to the tray body by locking this inner ridge to the outer peripheral edge of the tray body. Patent Documents 2 to 5 disclose containers in which the lid body can be attached to and detached from the tray body by rotating the lid body with respect to the tray body.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0004] The resin molded container disclosed in Patent Document 1 is excellent in airtightness before use, and even after opening, it has the convenience that the lid can be attached to and detached from the tray body. However, in order to form the inner ridge, as disclosed in Patent Document 1, in the molding process, the resin sheet must be molded and moved in two different directions, and for this purpose, a pressure difference must be applied to the resin sheet in two different directions. In addition, the attachment and detachment of the lid to and from the tray body utilize the elastic deformation of the outer peripheral edge of the tray body, so variations in the detachment performance due to manufacturing errors are likely to occur. The containers disclosed in Patent Documents 2 to 5 manufacture the tray body and the lid separately. The tray body that can accommodate the contents and the lid edge that is part of the lid that covers the tray opening are integrally molded, and the lid opening formed by the lid edge is covered with a top film. It is not a container in which the tray body and the lid are separated and used.

[0005] Therefore, an object of the present invention is to provide a resin molded container that is excellent in airtightness before use, can be attached to and detached from the tray body even after opening, and can provide a stable detachment function between the lid and the tray body, and a method for manufacturing this resin molded container.

Means for Solving the Problems

[0006] The resin molded container of the present invention according to claim 1 comprises a tray 10 consisting of a bottom surface 11 and a side surface 12, with a tray opening 13 formed by a side end portion 12a of the side surface 12, a ring-shaped edge portion 20 formed by extending outward from the side end portion 12a, and a lid edge portion 30 formed by rising from an outer peripheral end portion 20a of the ring-shaped edge portion 20, which are integrally molded by a resin material. A lid opening 33 formed by the lid edge portion 30 is covered with a top film 40. By separating the ring-shaped edge portion 20 into an inner peripheral side edge portion 21 and an outer peripheral side edge portion 22, the tray 10 and the inner peripheral side edge portion 21 form a tray body 1, and the lid edge portion 30, the outer peripheral side edge portion 22, and the top film 40 form a lid body 2 for use. In the lid edge portion 30, a convex portion 31 protruding in the direction of the ring-shaped edge portion 20 is formed. In the ring-shaped edge portion 20, a breaking line 23 for separating the inner peripheral side edge portion 21 and the outer peripheral side edge portion 22 is formed. The breaking line 23 is characterized in that at the position where the convex portion 31 is formed, the radial width of the inner peripheral side edge portion 21 is narrower than that at the position where the convex portion 31 is not formed. The present invention according to claim 2 is the resin molded container according to claim 1, wherein three or more convex portions 31 are formed. In the inner peripheral side edge portion 21, a narrow-width portion 21n at the position where the convex portion 31 is formed and a wide-width portion 21w at the position where the convex portion 31 is not formed are formed. The lid body 2 is attached to the tray body 1 by rotating the lid body 2 with respect to the tray body 1 and positioning the wide-width portion 21w between the convex portion 31 and the top film 40. The lid body 2 is removed from the tray body 1 by rotating the lid body 2 with respect to the tray body 1 so that the convex portion 31 is positioned in the narrow-width portion 21n. The present invention according to claim 3 is the resin molded container according to claim 1 or claim 2, wherein the upper surface 31u of the convex portion 31 of the convex portion 31 is made lower than the upper surface 30u of the lid edge portion 30 of the lid edge portion 30. The manufacturing method of the resin molded container according to claim 4 comprises a molding step of integrally molding, with a resin material, a tray 10 composed of a bottom surface 11 and a side surface 12, and having a tray opening 13 formed by a side end portion 12a of the side surface 12, a ring-shaped edge portion 20 formed to extend outward from the side end portion 12a, and a lid edge portion 30 formed by rising from an outer peripheral end portion 20a of the ring-shaped edge portion 20; a film arrangement step of arranging a top film 40 in a lid opening 33 formed by the lid edge portion 30; a separation step of separating the ring-shaped edge portion 20 into an inner peripheral side edge portion 21 and an outer peripheral side edge portion 22; and a sealing step of attaching the top film 40 to the lid edge portion 30. In the molding step, a convex portion 31 protruding in the direction of the ring-shaped edge portion 20 is formed on the lid edge portion 30, a breaking line 23 for separating the ring-shaped edge portion 20 into the inner peripheral side edge portion 21 and the outer peripheral side edge portion 22 is formed, and at a position where the convex portion 31 is formed, the radial width of the inner peripheral side edge portion 21 is formed to be narrower than that at a position where the convex portion 31 is not formed. The separation step and the sealing step are performed by pressing with a sealing plate 60. The invention according to claim 5 is the manufacturing method of the resin molded container according to claim 4, further comprising a housing step of housing the content 4 in the tray 10 after the molding step, and the separation step and the sealing step are performed after the housing step. The invention according to claim 6 is the manufacturing method of the resin molded container according to claim 5, wherein the content 4 is food, and in the sealing step, the top film 40 is attached to the inner peripheral side edge portion 21 together with the lid edge portion 30, and the inner peripheral side sealing strength between the top film 40 and the inner peripheral side edge portion 21 is made lower than the lid side sealing strength between the top film 40 and the lid edge portion 30. The invention according to claim 7 is the manufacturing method of the resin molded container according to any one of claims 4 to 6, wherein in the molding step, a resin sheet 3 is arranged in a mold 50, and the molding movement of the resin sheet 3 is performed by at least either pressurization from one surface of the resin sheet 3 or depressurization from the other surface of the resin sheet 3. [Effect of the Invention]

[0007] According to the resin-molded container of the present invention, a convex portion is formed at the lid edge, a breaking line is formed at the ring-shaped edge, and at the position where the convex portion is formed, the breaking line has a smaller radial width of the inner peripheral edge than at the position where the convex portion is not formed. Therefore, in a state where the ring-shaped edge is separated into an inner peripheral edge and an outer peripheral edge and used, by rotating the lid with respect to the tray body, an inner peripheral edge having a wide radial width is positioned between the convex portion and the top film, and the lid can be attached to the tray body. Also, by rotating the lid with respect to the tray body, an inner peripheral edge having a narrow radial width is positioned between the convex portion and the top film, and the lid can be removed from the tray body, providing a stable detaching function. Further, according to the manufacturing method of the resin-molded container of the present invention, the number of steps can be reduced by forming the breaking line in the molding step and performing the separation step and the sealing step with a sealing plate.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Mode for Carrying Out the Invention

[0009] The resin-molded container according to the first embodiment of the present invention is composed of a bottom surface and a side surface, and includes a tray in which a tray opening is formed by a side end portion of the side surface, a ring-shaped edge portion formed to extend outward from the side end portion, and a lid edge portion formed by rising from the outer peripheral end portion of the ring-shaped edge portion, which are integrally molded by a resin material. A convex portion protruding in the direction of the ring-shaped edge portion is formed on the lid edge portion, and a breaking line that separates into an inner peripheral side edge portion and an outer peripheral side edge portion is formed on the ring-shaped edge portion. The breaking line has a smaller radial width of the inner peripheral side edge portion at the position where the convex portion is formed than at the position where the convex portion is not formed. According to the present embodiment, since a convex portion is formed on the lid edge portion, a breaking line is formed on the ring-shaped edge portion, and the breaking line has a smaller radial width of the inner peripheral side edge portion at the position where the convex portion is formed than at the position where the convex portion is not formed, in a state where the ring-shaped edge portion is separated into an inner peripheral side edge portion and an outer peripheral side edge portion and used, by rotating the lid with respect to the tray body, an inner peripheral side edge portion having a wide radial width can be positioned between the convex portion and the top film, and the lid can be attached to the tray body. Also, by rotating the lid with respect to the tray body, an inner peripheral side edge portion having a narrow radial width can be positioned between the convex portion and the top film, and the lid can be removed from the tray body, providing a stable attaching and detaching function.

[0010] The second embodiment of the present invention is the resin-molded container according to the first embodiment, in which three or more convex portions are formed, and on the inner peripheral side edge portion, a narrow-width portion at the position where the convex portion is formed and a wide-width portion at the position where the convex portion is not formed are formed. By rotating the lid with respect to the tray body and positioning the wide-width portion between the convex portion and the top film, the lid is attached to the tray body. By rotating the lid with respect to the tray body so that the convex portion is positioned in the narrow-width portion, the lid is removed from the tray body. According to the present embodiment, in the use state, by rotating the lid with respect to the tray body, the lid can be attached to and removed from the tray body, providing a stable attaching and detaching function.

[0011] In the third embodiment of the present invention, in the resin-molded container according to the first or second embodiment, the upper surface of the convex portion is made lower than the upper surface of the lid body edge portion of the lid body edge. According to the present embodiment, by making the upper surface of the convex portion lower than the upper surface of the lid body edge portion, a space is formed between the upper surface of the convex portion and the top film in the use state, so that the inner peripheral side edge portion formed with a wide radial width can be smoothly positioned on the convex portion.

[0012] A method for manufacturing a resin-molded container according to a fourth embodiment of the present invention includes a tray formed of a bottom surface and a side surface, and a tray opening formed by a side end portion of the side surface, a ring-shaped edge portion formed by extending outward from the side end portion, and a lid body edge portion formed by rising from the outer peripheral end portion of the ring-shaped edge portion. A molding step of integrally molding with a resin material, a film arranging step of arranging a top film in a lid body opening formed by the lid body edge portion, a separating step of separating the ring-shaped edge portion into an inner peripheral side edge portion and an outer peripheral side edge portion, and a sealing step of attaching the top film to the lid body edge portion. In the molding step, a convex portion protruding in the direction of the ring-shaped edge portion is formed on the lid body edge portion, a breaking line for separating the ring-shaped edge portion into an inner peripheral side edge portion and an outer peripheral side edge portion is formed, and the breaking line is formed at a position where the convex portion is formed. The radial width of the inner peripheral side edge portion is made narrower than that at a position where the convex portion is not formed, and the separating step and the sealing step are performed by pressing with a sealing plate. According to the present embodiment, a convex portion is formed on the lid body edge portion, a breaking line is formed on the ring-shaped edge portion, and the breaking line is formed at a position where the convex portion is formed. The radial width of the inner peripheral side edge portion is made narrower than that at a position where the convex portion is not formed. Therefore, in a state where the ring-shaped edge portion is separated into an inner peripheral side edge portion and an outer peripheral side edge portion and used, by rotating the lid body with respect to the tray body, an inner peripheral side edge portion having a wide radial width is positioned between the convex portion and the top film, and the lid body can be attached to the tray body. At the same time, by rotating the lid body with respect to the tray body, an inner peripheral side edge portion having a narrow radial width is positioned between the convex portion and the top film, and the lid body can be removed from the tray body, providing a stable attaching / detaching function. According to this embodiment, the number of steps can be reduced by forming the broken line in the molding step and performing the separation step and the sealing step with a sealing plate.

[0013] The fifth embodiment of the present invention is a method for manufacturing a resin-molded container according to the fourth embodiment, which has a housing step of housing the contents in a tray after the molding step, and performs the separation step and the sealing step after the housing step. According to this embodiment, by performing the housing step after the molding step and before the separation step and the sealing step, the contents can be sealed while maintaining the predetermined environmental conditions.

[0014] The sixth embodiment of the present invention is a method for manufacturing a resin-molded container according to the fifth embodiment, wherein the contents are food, and in the sealing step, the top film is attached to the inner peripheral side edge together with the lid edge, and the inner peripheral side sealing strength between the top film and the inner peripheral side edge is made lower than the lid side sealing strength between the top film and the lid edge. It is such. According to this embodiment, by attaching the top film to the inner peripheral side edge as well, the sealed state in the tray containing the food can be maintained, and by making the inner peripheral side sealing strength lower than the lid side sealing strength, the inner peripheral side seal between the top film and the inner peripheral side edge can be peeled off to take out the food, and the lid with the top film attached can be repeatedly attached to and removed from the tray body.

[0015] The seventh embodiment of the present invention is a method for manufacturing a resin-molded container according to any one of the fourth to sixth embodiments. In the molding step, a resin sheet is placed in a mold, and the molding movement of the resin sheet is performed by at least either pressurization from one surface of the resin sheet or depressurization from the other surface of the resin sheet. According to this embodiment, the resin sheet can be molded by at least either pressurization from one surface of the resin sheet or depressurization from the other surface of the resin sheet, and high-precision and stable molding can be performed.

Example

[0016] Hereinafter, a resin molded container and a method for manufacturing the resin molded container according to an embodiment of the present invention will be described.

[0017] FIG. 1 is a view showing a resin molded container according to this embodiment. FIG. 1(a) is a perspective view of the resin molded container, FIG. 1(b) is an enlarged view of a main part of FIG. 1(a), FIG. 1(c) is an end view taken along line c-c of FIG. 1(b), and FIG. 1(d) is an end view taken along line d-d of FIG. 1(b).

[0018] In the resin molded container according to this embodiment, a tray 10, a ring-shaped edge portion 20, and a lid body edge portion 30 are integrally molded by a resin material. The tray 10 is composed of a bottom surface 11 and a side surface 12, and a tray opening 13 is formed by a side surface end portion 12a of the side surface 12. The ring-shaped edge portion 20 is formed to extend outward from the side surface end portion 12a. A break line 23 that separates into an inner peripheral side edge portion 21 and an outer peripheral side edge portion 22 is formed in the ring-shaped edge portion 20. The lid body edge portion 30 is formed to rise from an outer peripheral end portion 20a of the ring-shaped edge portion 20. A convex portion 31 that protrudes in the direction of the ring-shaped edge portion 20 is formed in the lid body edge portion 30. The upper surface 31u of the convex portion 31 is lower than the upper surface 30u of the lid body edge portion of the lid body edge portion 30. In addition, a skirt portion 32 that extends downward from the outer peripheral end portion 30a of the lid body edge portion 30 is provided in the lid body edge portion 30, but when the strength of the lid body edge portion 30 is sufficiently high, the skirt portion 32 may be omitted.

[0019] At the position where the convex portion 31 is formed, the break line 23 narrows the radial width of the inner peripheral side edge portion 21 more than at the position where the convex portion 31 is not formed. That is, a narrow portion 21n at the position where the convex portion 31 is formed and a wide portion 21w at the position where the convex portion 31 is not formed are formed in the inner peripheral side edge portion 21.

[0020] FIG. 2 is a view showing the usage state of the resin molded container. FIG. 2(a) is a perspective view of the lid of the resin molded container, FIG. 2(b) is a perspective view of the tray body of the resin molded container, FIG. 2(c) is an end view taken along the c-c line of FIG. 2(a), FIG. 2(d) is an end view taken along the d-d line of FIG. 2(a), FIG. 2(e) is an end view taken along the e-e line of FIG. 2(b), FIG. 2(f) is an end view taken along the f-f line of FIG. 2(b), FIG. 2(g) is an end view of the state where the lid is attached to the tray body, and FIG. 2(h) is an end view of the state where the lid is removed from the tray body.

[0021] In the resin molded container according to this embodiment, the lid opening 33 formed by the lid edge 30 is covered with the top film 40, and by separating the ring-shaped edge 20 into an inner peripheral side edge 21 and an outer peripheral side edge 22, the tray 10 and the inner peripheral side edge 21 become the tray body 1, and the lid edge 30, the outer peripheral side edge 22, and the top film 40 become the lid 2 and are used.

[0022] FIG. 2(g) shows a state where the lid 2 is rotated with respect to the tray body 1 and the wide portion 21w is positioned between the convex portion 31 and the top film 40. In this state, the lid 2 can be attached to the tray body 1. The state of FIG. 2(g) is obtained by positioning the wide portion 21w shown in FIG. 2(f) at the position where the convex portion 31 shown in FIG. 2(c) is formed. FIG. 2(h) shows a state where the lid 2 is rotated with respect to the tray body 1 and the convex portion 31 is positioned at the narrow portion 21n. In this state, the lid 2 can be removed from the tray body 1. The state of FIG. 2(h) is obtained by positioning the narrow portion 21n shown in FIG. 2(e) at the position where the convex portion 31 shown in FIG. 2(c) is formed.

[0023] In this embodiment, although ten convex portions 31 are shown to be formed at equal intervals, by forming at least one convex portion 31 and at least one wide portion 21w, the states of FIGS. 2(g) and 2(h) can be achieved, and the lid 2 can be attached to the tray body 1 and the lid 2 can be removed from the tray body 1. By forming three or more convex portions 31, the lid 2 can be surely attached to the tray body 1. Further, particularly when the top film 40 has elasticity or flexibility, the upper surface 31u of the convex portion may be at the same height as the upper surface 30u of the lid body edge portion.

[0024] Thus, according to this embodiment, in the use state, by rotating the lid body 2 with respect to the tray body 1, the lid body 2 can be attached to and detached from the tray body 1, providing a stable attaching and detaching function. Also, according to this embodiment, no matter in which direction the lid body 2 is rotated with respect to the tray body 1, the lid body 2 can be simply fixed to the tray body 1. Further, by further rotating from the simple fixing position, the simple fixing is released, and by further rotating, it can be simply fixed again. Also, as in this embodiment, by making the upper surface 31u of the convex portion lower than the upper surface 30u of the lid body edge portion, a space is formed between the upper surface 31u of the convex portion and the top film 40 in the use state. Therefore, even if the top film 40 does not have elasticity or flexibility, the inner peripheral side edge portion 21 formed with a wide radial width can be smoothly positioned on the convex portion 31.

[0025] FIG. 3 is a diagram showing a manufacturing method of the resin molded container. FIG. 3(a) shows the molding step, FIG. 3(b) shows the cutting step, FIG. 3(c) shows the content accommodating step, FIG. 3(d) shows the top film arranging step, FIG. 3(e) shows the separating step, and FIG. 3(f) shows the sealing step.

[0026] In the molding step shown in FIG. 3(a), the resin sheet 3 is placed in the mold 50, and by applying pressure from one surface of the resin sheet 3, the resin sheet 3 is made to conform to the mold 50. That is, the molding movement of the resin sheet 3 is in one direction. Instead of applying pressure from one surface of the resin sheet 3, a negative pressure may be applied from the other surface of the resin sheet 3, or pressure may be applied from one surface of the resin sheet 3 and a negative pressure may be applied from the other surface of the resin sheet 3. Note that the molding step in this embodiment shows blow molding, but it may also be injection molding. By the molding process shown in Fig. 3(a), a tray 10 composed of a bottom surface 11 and side surfaces 12 with a tray opening 13 formed by side end portions 12a of the side surfaces 12, a ring-shaped edge portion 20 formed to extend outward from the side end portions 12a, and a lid edge portion 30 formed by rising from the outer peripheral end portion 20a of the ring-shaped edge portion 20 are integrally molded. In this molding process, a convex portion 31 protruding in the direction of the ring-shaped edge portion 20 is formed on the lid edge portion 30. By the molding process, the resin molded container shown in Fig. 1 is molded.

[0027] In the cutting process shown in Fig. 3(b), a cutting blade 51 is used to form a breaking line 23 that separates the ring-shaped edge portion 20 into an inner peripheral side edge portion 21 and an outer peripheral side edge portion 22, and the outer periphery of the lid edge portion 30 is cut. After forming the breaking line 23, it is preferable to cut the outer periphery of the lid edge portion 30. The cutting of the outer periphery of the lid edge portion 30 may be performed by the time of the top film placement process. The breaking line 23 forms the radial width of the inner peripheral side edge portion 21 narrower at the position where the convex portion 31 is formed than at the position where the convex portion 31 is not formed. The inner peripheral side edge portion 21 and the outer peripheral side edge portion 22 are partially connected along the breaking line 23.

[0028] In the accommodating process shown in Fig. 3(c), the tray 10 is filled with the content 4. As the content 4, those that need to maintain the storage state under predetermined environmental conditions, such as foods, electronic components, or precision mechanical components, are suitable. In the accommodating process, the tray 10 is placed in a closed space, the inside of this closed space is evacuated, and a gas selected according to the content 4 is enclosed.

[0029] In the top film placement process shown in Fig. 3(d), a top film 40 is placed in a lid opening 33 formed by the lid edge portion 30. The lid opening 33 is covered with the top film 40.

[0030] In the separation process shown in Fig. 3(e), by pressing the lid edge portion 30 from one surface of the top film 40 with a seal plate 60, the ring-shaped edge portion 20 is separated into an inner peripheral side edge portion 21 and an outer peripheral side edge portion 22 along the breaking line 23. When the upper surface of the lid edge 30 reaches approximately the same height as the upper surface of the inner peripheral edge 21 in this separation step, the seal plate 60 presses the inner peripheral edge 21 from one surface of the top film 40.

[0031] In the sealing step shown in FIG. 3(f), the seal plate 60 heats the top film 40. The seal plate 60 preferably includes a first seal plate 61 that presses the lid edge 30 and a second seal plate 62 that presses the inner peripheral edge 21. When the first seal plate 61 and the second seal plate 62 are provided, the top film 40 is attached to the lid edge 30 by the first seal plate 61, and the top film 40 is attached to the inner peripheral edge 21 by the second seal plate 62 (sealing step). Heat sealing is suitable for the sealing step. The inner peripheral side seal strength between the top film 40 and the inner peripheral edge 21 is preferably lower than the lid side seal strength between the top film 40 and the lid edge 30. For this purpose, the heating temperature of the first seal plate 61 is made higher than the heating temperature of the second seal plate 62. Note that the first seal plate 61 and the second seal plate 62 may be a single plate structurally as long as they can attach the top film 40 to the lid edge 20 and the inner peripheral edge 21 while avoiding the convex portion 31. By sealing the top film 40 and the inner peripheral edge 21 on the inner peripheral side, the inside of the tray 10 after manufacturing is kept in a vacuum state or a state filled with an enclosed gas. When the lid 2 is first removed from the tray body 1 after manufacturing, the top film 40 is peeled off from the inner peripheral edge 21, but the lid side seal between the top film 40 and the lid edge 30 maintains the sealed state without peeling. Therefore, once the lid 2 is removed from the tray body 1, air in the atmosphere flows into the tray 10, but the tray body 1 can be simply sealed with the lid 2 in which the lid opening 33 is covered with the top film 40.

[0032] As described above, according to this embodiment, the convex portion 31 is formed on the lid body edge portion 30, the broken line 23 is formed on the ring-shaped edge portion 20, and at the position where the convex portion 31 is formed, the radial width of the inner peripheral edge portion 21 is made narrower than that at the position where the convex portion 31 is not formed for the broken line 23. Therefore, in a state where the ring-shaped edge portion 20 is separated into the inner peripheral edge portion 21 and the outer peripheral edge portion 22 and used, by rotating the lid body 2 with respect to the tray body 1, the inner peripheral edge portion 21 with a wide radial width is positioned between the convex portion 31 and the top film 40, and the lid body 2 can be attached to the tray body 1. Also, by rotating the lid body 2 with respect to the tray body 1, the inner peripheral edge portion 21 with a narrow radial width is positioned between the convex portion 31 and the top film 40, and the lid body 2 can be removed from the tray body 1, providing a stable attaching / detaching function. Further, according to this embodiment, by forming the broken line 23 in the molding process and performing the separation process and the sealing process with the sealing plate 60, the number of processes can be reduced. Further, according to this embodiment, by performing the accommodation process after the molding process and before the separation process and the sealing process, the content 4 can be sealed while maintaining it under predetermined environmental conditions. Further, according to this embodiment, by using the content 4 as food and attaching the top film 40 to the inner peripheral edge portion 21 as well, the sealed state inside the tray 10 containing the food can be maintained. Also, by making the inner peripheral side seal strength lower than the lid body side seal strength, the inner peripheral side seal between the top film 40 and the inner peripheral edge portion 21 can be peeled off to take out the food, and the lid body 2 with the top film 40 attached can be repeatedly attached to and detached from the tray body 1. Further, according to this embodiment, the resin sheet 3 can be molded by at least either pressurization from one surface of the resin sheet 3 or depressurization from the other surface of the resin sheet 3, enabling highly accurate and stable molding.

[0033] Resin molded containers according to other embodiments of the present invention are shown in FIGS. 4 to 10.

[0034] FIG. 4 is a view showing a resin molded container according to this embodiment. FIG. 4(a) is a perspective view of the resin molded container, and FIG. 4(b) is an enlarged view of the main part of FIG. 4(a). FIG. 5 is a plan view of the main part of the resin molded container, and FIG. 6 is an end view of the main part of the resin molded container. FIG. 6(a) is an end view taken along line a-a of FIG. 4(a), FIG. 6(b) is an end view taken along line b-b of FIG. 4(a), FIG. 6(c) is an end view taken along line c-c of FIG. 4(a), and FIG. 6(d) is an end view taken along line d-d of FIG. 4(a).

[0035] As shown in FIG. 4, in the resin molded container according to this embodiment, a tray 10, a ring-shaped edge portion 20, and a lid edge portion 30 are integrally molded of a resin material. The tray 10 is composed of a bottom surface 11 and side surfaces 12, and a tray opening 13 is formed by side surface end portions 12a of the side surfaces 12. The ring-shaped edge portion 20 is formed to extend outward from the side surface end portion 12a. A breaking line 23 that separates into an inner peripheral side edge portion 21 and an outer peripheral side edge portion 22 is formed in the ring-shaped edge portion 20. A contact portion 24 formed by a groove is provided on the inner peripheral side edge portion 21. Further, a ring-shaped convex portion 25 is provided on the inner peripheral side of the inner peripheral side edge portion 21. The lid edge portion 30 is formed to rise from the outer peripheral end portion 20a of the ring-shaped edge portion 20. A convex portion 31 that protrudes in the direction of the ring-shaped edge portion 20 is formed in the lid edge portion 30. The convex portion 31 is composed of a first convex portion 31a and a second convex portion 31b formed at one end of the first convex portion 31a.

[0036] The convex portion 31 and the breaking line 23 will be described with reference to FIG. 5. The arrow X in the figure indicates the rotational direction of the lid body 2 with respect to the tray body 1 when the inner peripheral side edge portion 21 and the outer peripheral side edge portion 22 are separated by the breaking line 23 and the lid body 2 is simply fixed to the tray body 1 when used as the tray body 1 and the lid body 2. One end of the second convex portion 31b is formed with a predetermined angle 31α with respect to the radial direction Y. By providing the predetermined angle 31α, one end of the second convex portion 31b is at a position where the outer peripheral end has advanced in the direction of the arrow X from the inner peripheral end. The other end of the second convex portion 31b is continuous with the first convex portion 31a. The inner peripheral end portion 34 of the lid body from the other end of the first convex portion 31a to the outer peripheral end of one end of the second convex portion 31b forming the other convex portion 31 has a gradually increasing radius of curvature. The broken line 23 gradually increases the radius of curvature along the inner peripheral end portion 34 of the lid body from the other end of the first convex portion 31a toward one end of the second convex portion 31b forming the other convex portion 31. At the position where the convex portion 31 is formed, the radial width of the inner peripheral side edge portion 21 is made narrower than at the position where the convex portion 31 is not formed. That is, on the inner peripheral side edge portion 21, a narrow portion 21n at the position where the convex portion 31 is formed and a wide portion 21w at the position where the convex portion 31 is not formed are formed. The contact portion 24 is formed with a predetermined angle 24α with respect to the radial direction Y. The predetermined angle 24α of the contact portion 24 is made slightly larger than the predetermined angle 31α of one end of the second convex portion 31b. By setting one end of the second convex portion 31b as the predetermined angle 31α and the contact portion 24 as the predetermined angle 24α, when the lid body 2 is rotated in the X direction with respect to the tray body 1, first, the inner peripheral end of the second convex portion 31b comes into contact with the inner side end of the contact portion 24, and then, the contact range between the second convex portion 31b and the contact portion 24 gradually increases. Therefore, the lid body 2 can be smoothly and simply fixed to the tray body 1.

[0037] As shown in FIG. 6(a), the upper surface 31au of the first convex portion 31a of the first convex portion 31a is lower than the upper surface 30u of the lid body edge portion 30 of the lid body edge portion 30. Also, as shown in FIG. 6(b), the upper surface 31bu of the second convex portion 31b of the second convex portion 31b is lower than the upper surface 30u of the lid body edge portion 30 of the lid body edge portion 30, and the inner peripheral end is lower than the outer peripheral end. The upper surface 31bu of the second convex portion is set to the same height as the other end on the side of the first convex portion 31a with respect to the upper surface 31au of the first convex portion, and one end of the upper surface 31bu of the second convex portion is made lower than the other end of the upper surface 31bu of the second convex portion to form an inclined surface. As shown in FIG. 6(c), the contact portion 24 is formed in the wide portion 21w of the inner peripheral side edge portion 21 by a groove that is lower than the inner peripheral side edge portion 21. In addition, ring-shaped convex portions 25 are formed on the narrow-width portions 21n and the wide-width portions 21w. When the inner peripheral side edge portion 21 and the outer peripheral side edge portion 22 are separated by the broken line 23 and used as the tray body 1 and the lid body 2, the inner peripheral side edge portion 21 can maintain sufficient strength by this ring-shaped convex portion 25. Note that a skirt portion 32 extending downward from the outer peripheral end portion 30a of the lid body edge portion 30 is provided on the lid body edge portion 30. However, when the strength of the lid body edge portion 30 is sufficiently high, the skirt portion 32 may not be provided.

[0038] FIG. 7 is a view showing the usage state of the resin molded container. FIG. 7(a) is a perspective view of the lid body of the resin molded container, and FIG. 7(b) is a perspective view of the tray body of the resin molded container. Further, FIG. 8(a) is an end view taken along line a-a of FIG. 7, FIG. 8(b) is an end view taken along line b-b of FIG. 7, FIG. 8(c) is an end view taken along line c-c of FIG. 7, and FIG. 8(d) is an end view taken along line d-d of FIG. 7.

[0039] In the resin molded container according to the present embodiment, the lid body opening 33 formed by the lid body edge portion 30 is covered with the top film 40, and by separating the ring-shaped edge portion 20 into the inner peripheral side edge portion 21 and the outer peripheral side edge portion 22, the tray 10 and the inner peripheral side edge portion 21 become the tray body 1, and the lid body edge portion 30, the outer peripheral side edge portion 22, and the top film 40 become the lid body 2 and are used.

[0040] FIG. 9(a) is a perspective view of a main part showing a state where the lid body can be removed from the tray body, FIG. 9(b) is a cross-sectional view taken along line a-a of FIG. 9(a), and FIG. 9(c) is a cross-sectional view taken along line b-b of FIG. 9(a). FIG. 9 shows a state where the lid body 2 is rotated with respect to the tray body 1 and the convex portion 31 is positioned at the narrow-width portion 21n. In this state, the lid body 2 can be removed from the tray body 1.

[0041] FIG. 10(a) is a perspective view of a main part showing a state where the lid body is being attached to the tray body, FIG. 10(b) is a cross-sectional view taken along line c-c of FIG. 10(a), FIG. 10(c) is a cross-sectional view taken along line d-d of FIG. 10(a), and FIG. 10(d) is a cross-sectional view taken along line e-e of FIG. 10(a). FIG. 10 shows a state in which the lid body 2 is rotated in the X direction with respect to the tray body 1 from the state of FIG. 9, and the wide portion 21w is positioned between the convex portion 31 and the top film 40. In this state, the contact portion 24 has not yet contacted the convex portion 31.

[0042] FIG. 11(a) is a perspective view of the main part showing the state where the lid body is attached to the tray body, FIG. 11(b) is a cross-sectional view taken along line f-f of FIG. 11(a), FIG. 11(c) is a cross-sectional view taken along line g-g of FIG. 11(a), and FIG. 11(d) is a cross-sectional view taken along line h-h of FIG. 11(a). FIG. 11 shows a state in which the lid body 2 is further rotated in the X direction with respect to the tray body 1 from the state of FIG. 10, and the lid body 2 is attached to the tray body 1. In this state, the contact portion 24 is in contact with the convex portion 31. In FIG. 11, the contact portion 24 is in contact with the first convex portion upper surface 31au of the first convex portion 31a, but the attachment of the lid body 2 to the tray body 1 may be completed by bringing the contact portion 24 into contact with the second convex portion upper surface 31bu of the second convex portion 31b.

[0043] In this embodiment, five convex portions 31 are formed at equal intervals, but by forming at least one convex portion 31 and at least one wide portion 21w, the state of FIG. 11 can be obtained, the lid body 2 can be attached to the tray body 1, and the lid body 2 can be removed from the tray body 1. By forming three or more convex portions 31, the lid body 2 can be surely attached to the tray body 1. Further, particularly when the top film 40 has elasticity or flexibility, the convex portion upper surface 31u may be at the same height as the lid body edge upper surface 30u. Also, the resin molded container according to the present embodiment can also be manufactured by the manufacturing method shown in FIG. 3. Therefore, by sealing the top film 40 and the inner peripheral side edge portion 21 on the inner peripheral side, the inside of the tray 10 after manufacturing is maintained in a vacuum state or a state filled with an enclosed gas. When the lid body 2 is first removed from the tray body 1 after manufacturing, the top film 40 is peeled off from the inner peripheral side edge portion 21, but the lid body side seal between the top film 40 and the lid body edge portion 30 remains sealed without being peeled off. Therefore, once the lid body 2 is removed from the tray body 1, air in the atmosphere flows into the tray 10, but the tray body 1 can be simply sealed with the lid body 2 in which the lid body opening 33 is covered with the top film 40.

[0044] As described above, according to the present embodiment, in the use state, by rotating the lid body 2 with respect to the tray body 1, the lid body 2 can be attached to and removed from the tray body 1, and a stable attaching / detaching function can be provided. Further, according to the present embodiment, since the contact portion 24 comes into contact with and is locked to the first convex portion 31a, the lid body 2 can be firmly and simply fixed to the tray body 1. Also, as in the present embodiment, by making the upper surface 31u of the convex portion lower than the upper surface 30u of the lid body edge portion, a space is formed between the upper surface 31u of the convex portion and the top film 40 in the use state. Therefore, even if the top film 40 does not have elasticity or flexibility, the inner peripheral side edge portion 21 having a wide radial width can be smoothly positioned on the convex portion 31.

[0045] As described above, according to the present embodiment, the convex portion 31 is formed on the lid body edge portion 30, the break line 23 is formed on the ring-shaped edge portion 20, and at the position where the convex portion 31 is formed, the break line 23 makes the radial width of the inner peripheral edge portion 21 narrower than that at the position where the convex portion 31 is not formed. Therefore, in a state where the ring-shaped edge portion 20 is separated into the inner peripheral edge portion 21 and the outer peripheral edge portion 22 and used, by rotating the lid body 2 with respect to the tray body 1, the inner peripheral edge portion 21 having a wide radial width is positioned between the convex portion 31 and the top film 40, and the lid body 2 can be attached to the tray body 1. Also, by rotating the lid body 2 with respect to the tray body 1, the inner peripheral edge portion 21 having a narrow radial width is positioned between the convex portion 31 and the top film 40, and the lid body 2 can be removed from the tray body 1, providing a stable attaching / detaching function.

Industrial Applicability

[0046] According to the present invention, it has excellent airtightness before use and a stable attaching / detaching function between the lid body and the tray body, and thus is particularly suitable for a resin molded container using food as its content.

Explanation of Reference Numerals

[0047] 1 Tray body 2 Lid body 3 Resin sheet 4 Content 10 Tray 11 Bottom surface 12 Side surface 12a Side surface end 13 Tray opening 20 Ring-shaped edge portion 20a Outer peripheral end 21 Inner peripheral edge portion 21n Narrow-width portion 21w Wide-width portion 22 Outer peripheral edge portion 23 Break line 24 Contact portion 24α Predetermined angle 25 Convex portion 30 Lid body edge portion 30a Outer peripheral end Upper surface of the edge of the 30u cover 31 Protrusion 31a First protrusion Upper surface of the 31au first protrusion 31b Second protrusion Upper surface of the 31bu second protrusion Upper surface of the 31u protrusion 31α Specified angle 32 Skirt part 33 Cover opening Inner peripheral end of the 34 cover 40 Top film 50 Mold 51 Punching tool 60 Seal plate 61 First seal plate 62 Second seal plate

Claims

1. A tray comprising a bottom surface and side surfaces, with a tray opening formed by side ends of the side surfaces, A ring-shaped edge formed by extending outward from the side ends, A lid edge formed by rising from the outer peripheral end of the ring-shaped edge, which are integrally formed of a resin material, The lid opening formed by the lid edge is covered with a top film, By separating the ring-shaped edge into an inner peripheral edge and an outer peripheral edge, the tray and the inner peripheral edge become a tray body, and the lid edge, the outer peripheral edge, and the top film become a lid and are used as a resin-molded container, On the lid edge, a convex portion protruding in the direction of the ring-shaped edge is formed, On the ring-shaped edge, a breaking line for separating the inner peripheral edge and the outer peripheral edge is formed, The breaking line makes the radial width of the inner peripheral edge narrower at the position where the convex portion is formed than at the position where the convex portion is not formed, A resin-molded container characterized by the above.

2. Three or more of the convex portions are formed, On the inner peripheral edge, a narrow-width portion at the position where the convex portion is formed and a wide-width portion at the position where the convex portion is not formed are formed, By rotating the lid with respect to the tray body and positioning the wide-width portion between the convex portion and the top film, the lid is attached to the tray body, By rotating the lid with respect to the tray body so that the convex portion is positioned in the narrow-width portion, the lid is removed from the tray body, The resin-molded container according to claim 1, characterized by the above.

3. The upper surface of the convex portion of the convex portion is made lower than the upper surface of the lid edge of the lid edge, The resin-molded container according to claim 1 or claim 2, characterized by the above.

4. A tray composed of a bottom surface and side surfaces, with a tray opening formed by side ends of the side surfaces, a ring-shaped edge formed by extending outward from the side ends, and a lid edge formed by rising from the outer peripheral end of the ring-shaped edge are integrally molded from a resin material in a molding step; A film placement step of placing a top film in a lid opening formed by the lid edge; A separation step of separating the ring-shaped edge into an inner peripheral side edge and an outer peripheral side edge; A sealing step of attaching the top film to the lid edge; and having; In the molding step, A convex portion protruding in the direction of the ring-shaped edge is formed on the lid edge, A breaking line for separating the ring-shaped edge into the inner peripheral side edge and the outer peripheral side edge is formed, At the position where the convex portion is formed, the breaking line is formed such that the radial width of the inner peripheral side edge is narrower than that at the position where the convex portion is not formed, The separation step and the sealing step are performed by pressing with a sealing plate. A method for manufacturing a resin molded container, characterized in that.

5. After the molding step, it has a housing step of housing contents in the tray, The separation step and the sealing step are performed after the housing step. The method for manufacturing a resin molded container according to claim 4, characterized in that.

6. The contents are food, In the sealing step, the top film is attached to the inner peripheral side edge together with the lid edge, and the inner peripheral side sealing strength between the top film and the inner peripheral side edge is made lower than the lid side sealing strength between the top film and the lid edge. The method for manufacturing a resin molded container according to claim 5, characterized in that.

7. In the molding step, a resin sheet is placed in a mold, The forming movement of the resin sheet is performed by at least one of pressurization from one surface of the resin sheet and depressurization from the other surface of the resin sheet. A method for manufacturing a resin molded container according to any one of claims 4 to 6, characterized in that.

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