JP2010264983A - Plastic container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plastic bottle which can be stored by vertically stacking the containers up each other, has inner pressure resistance, and furthermore provides heat resistance. <P>SOLUTION: A plastic container consisting of a container body, a mouth plug part, and a cap screwed on the mouth plug part is characterized in that the container body has a bottom face, a barrel part and a shoulder part, wherein the mouth plug part is recessed from the shoulder part and forms a recessed part around the mouth plug part, and the shoulder part forms an uppermost face of the container. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a plastic container having a screw-in type cap, and relates to a plastic container having a shape that can be stacked and having excellent heat resistance and pressure resistance.

  As the shape of the plastic bottle, the so-called bottle shape with a cylindrical or square columnar body is common, but if it is a vertically long bottle shape, it can not be stacked and stored, so it is for business use etc. Therefore, it is unsuitable for applications in which storage is more important when storing stock.

  What is stacked in a large container used for business purposes is a so-called bag-in-box that contains a flexible packaging bag mainly made of polyolefin resin with a cap with a cap inside a cardboard box. Is used. The bag-in-box cannot be used for a liquid in which an internal pressure due to gas is generated because the wetted part is a soft packaging bag.

  On the other hand, plastic containers of various materials and shapes are known. The container that has a screw-in type cap and is most commonly used for beverages is a so-called PET bottle, which is obtained by reheating a preform made by injection molding of polyethylene terephthalate resin (PET resin). Manufactured by a stretch blow molding method to process into a bottle shape. The PET bottle can withstand a certain amount of internal pressure by devising the shape. When filling carbonated drinks or beer, the container is required to have pressure resistance that can withstand the internal pressure of carbon dioxide gas, and therefore, a pressure bottle container having a groove or a constriction in the body or bottom of the bottle is used.

  The pressure-resistant bottle container described in Patent Document 1 has a constriction portion that gradually reduces the diameter of the body portion as described in the claims, and the constriction portion protrudes in the radial direction and protrudes in the axial direction. In a pressure-resistant bottle container made of resin with an extended concavo-convex pattern, the height difference of the concavo-convex pattern is minimized at the minimum diameter portion in the constricted portion, and increases as the distance from the minimum diameter portion increases in the axial direction. It is a pressure-resistant bottle container characterized by. This pressure-resistant bottle container can suppress the deformation of the container to be small by making the height difference of the concave and convex pattern the smallest in the constricted part of the central part of the bottle which is most likely to be deformed by the internal pressure. .

JP-A-7-125737

  Since the pressure bottle container described in Patent Document 1 has a vertically long general bottle shape, it cannot be stacked and stored. The problem to be solved by the present invention is to propose a plastic bottle capable of storing containers stacked vertically, having internal pressure resistance, and capable of imparting heat resistance. is there.

As a means for solving the above-mentioned problems, the invention according to claim 1 is a plastic container comprising a container main body, a plug part, and a cap screwed into the plug part. The plastic container is characterized in that the plug part is recessed from the shoulder part to form a concave part around the plug part, and the shoulder part forms the uppermost surface of the container.

  The invention according to claim 2 is a plastic container comprising a container main body, a plug part, and a cap screwed into the plug part. The container main body has a bottom surface, a trunk part, and a shoulder part. The plug portion is a plastic container characterized in that the stopper portion is recessed from the shoulder portion to form a recess around the plug portion, and a plane including the vertices of a plurality of reinforcing protrusions provided on the shoulder portion forms the uppermost surface of the container.

  Further, the invention according to claim 3 is characterized in that it has a bottom surface peripheral protrusion on the peripheral edge of the bottom surface, and a shoulder peripheral groove having a shape in which the bottom peripheral protrusion fits on the peripheral edge of the shoulder. 1. The plastic container according to 1.

  According to a fourth aspect of the present invention, there is provided a bottom edge protrusion on the periphery of the bottom surface, and the bottom edge protrusion is shaped to fit a reinforcing protrusion provided on the shoulder. It is a plastic container as described in above.

  The invention according to claim 5 is the plastic container according to any one of claims 1 to 4, wherein a reinforcing rib is provided on the bottom surface.

  The invention according to claim 6 is characterized in that the material constituting the plug portion is a thermoplastic polyester resin, and the heat resistance is improved by reheating the plug portion to cause crystallization. Item 6. The plastic container according to any one of Items 1 to 5.

  The plastic container according to the present invention is a plastic container comprising a container main body, a cap part, and a cap screwed into the plug part. The container main body has a bottom face, a trunk part, and a shoulder part. Since the mouth portion is recessed from the shoulder portion to form a concave portion around the stopper portion, and the shoulder portion forms the uppermost surface of the container, the upper surface of the container is flat without protrusion of the stopper. For this reason, containers can be directly stacked. In addition, since the plug portion is depressed from the shoulder portion to form the concave portion around the plug portion, the container structure is sturdy with many walls and has high pressure resistance.

  Further, in a plastic container in which a plurality of reinforcing protrusions are provided on the shoulder portion and a plane including the tops of the reinforcing protrusions forms the uppermost surface of the container, the pressure resistance is further improved. In addition, when a reinforcing rib is provided on the bottom surface, this pressure resistance is further improved.

  When a bottom edge protrusion is provided on the periphery of the bottom surface and a shoulder edge groove having a shape that fits the bottom edge protrusion is provided on the periphery of the shoulder, the container slides and shifts to the side when stacked. It is easily possible to stack straight without any problems. Further, in the second aspect of the present invention, the same applies to a case where a bottom surface peripheral protrusion is provided on the peripheral edge of the bottom surface, and the bottom surface peripheral protrusion is fitted to a reinforcing protrusion provided on the shoulder.

  In addition, when the material constituting the plug part is a thermoplastic polyester resin and the heat resistance is improved by reheating the plug part and crystallizing it, the container can be heated and used safely. It can be used with care.

FIG. 1 is a schematic cross-sectional view showing an embodiment of a plastic container according to the present invention, and shows the AA cross-section of FIG. FIG. 2 is a schematic plan view of the plastic container shown in FIG. FIG. 3 is a schematic cross-sectional view showing another embodiment of the plastic container according to the present invention, and shows the BB cross-section of FIG. FIG. 4 is a schematic plan view of the plastic container shown in FIG. FIG. 5 is a schematic cross-sectional view showing a state in which the plastic containers shown in FIGS. 1 and 2 are stacked. FIG. 6 is a cross-sectional explanatory view showing a method for recrystallization of the stopper portion of the plastic container according to the present invention for crystallization. FIG. 7 is a schematic cross-sectional view showing a conventional plastic container. FIG. 8 is a schematic cross-sectional view of a preform for molding the plastic container shown in FIG.

The plastic container according to the present invention will be described in detail below with reference to the drawings.
1 and 2 are schematic views showing an embodiment of a plastic container according to the present invention. FIG. 1 is a schematic cross-sectional view showing the AA cross section of FIG. 2, and FIG. 2 is a schematic plan view.
The plastic container according to the present invention is a plastic container comprising a container body 1, a cap part 2, and a cap 3 screwed into the plug part 2, and the container body 1 has a bottom face 4, a trunk part 5 and a shoulder part 6. The plug portion 2 is a plastic container that is recessed from the shoulder portion 6 to form a concave portion 7 around the plug portion, and the shoulder portion 6 forms the uppermost surface of the container.

  In this embodiment, the bottom surface peripheral protrusion 9 is provided on the peripheral edge of the bottom surface 4, and the shoulder peripheral groove 8 is formed on the peripheral edge of the shoulder portion 6 so that the bottom surface peripheral protrusion 9 is fitted. In FIG. 1, a dotted line below the bottom surface 4 represents the upper part of the lower container 15 and shows a state where the containers are stacked. As described above, in the plastic container according to the present invention, the plug part 2 is recessed from the shoulder part 6 so that it is lower or at the same height as the shoulder part 6, and the shoulder part 6 forms the uppermost surface of the container. Therefore, containers can be stacked vertically. As in this embodiment, when the bottom surface peripheral protrusion 9 is provided on the peripheral edge of the bottom surface 4 and the shoulder peripheral groove 8 having a shape that the bottom peripheral peripheral protrusion 9 is fitted on the peripheral edge of the shoulder portion 6, Since the two fit together, they can be safely stacked without the upper container slipping sideways and falling.

  In the plastic container according to the present invention, as the plug portion 2 is depressed from the shoulder portion 6, as can be seen from the schematic cross-sectional view, the number of vertical walls increases, and thus the limit of usable internal pressure increases. FIG. 7 shows a modification of the shape of the bottom surface of a conventional plastic bottle, in which a cap storage space 12 is provided in the center of the bottom surface 4 so that the containers can be stacked vertically. In this case, there is a drawback that the uppermost surface does not become flat when stacked, but it is inferior to the container according to the present invention from the viewpoint of the internal pressure resistance of each container.

  When the plug portion 2 is depressed from the shoulder portion 6, a concave portion 7 around the plug portion is formed. The width of the concave portion around the plug portion is determined by considering the operability when opening the plug. Can be inserted, it needs a certain width. At least about 15 mm is necessary, and 20 mm or more is desirable.

3 and 4 are schematic views showing another embodiment of the plastic container according to the present invention. FIG. 3 is a schematic cross-sectional view showing the BB cross-section of FIG. 4, and FIG. 4 is a schematic plan view.
In this embodiment, the container main body has a bottom surface 4, a body portion 5, and a shoulder portion 6, and the plug portion 2 is recessed from the shoulder portion 6 to form a plug portion peripheral recess 7, and is provided on the shoulder portion 6. Further, the plane including the apexes of the eight reinforcing protrusions 13 forms the uppermost surface of the container. Thus, by providing the reinforcing protrusion 13 on the upper surface of the shoulder portion 6, the internal pressure resistance of the container is improved. The shape of the reinforcing protrusion 13 is not limited to a shape corresponding to a part of a spherical surface as shown in the figure, and may be a shape such as an elongated rib shape or a kamaboko shape. In this embodiment, the bottom surface peripheral protrusion 8 is provided on the peripheral edge of the bottom surface 4, and the bottom surface peripheral protrusion 8 is shaped to be fitted to the reinforcing protrusion 13 provided on the shoulder 6. Therefore, as shown by a dotted line in FIG. 3, when stacked on the lower container 15, it can be stably stacked without slipping and shifting sideways. In this embodiment, reinforcing ribs 14 are provided on the bottom surface 4. By providing the reinforcing rib 14, the internal pressure resistance of the container is further increased. The shape of the reinforcing rib 14 is not particularly limited. However, it is desirable that the reinforcing rib 14 has a shape that does not interfere with the reinforcing protrusions 13 of the lower container when stacked.

  As in this embodiment, when the reinforcing projection 13 is provided on the shoulder 6, the height of the plug portion 2 is made higher than the height of the shoulder 6 by an amount corresponding to the height of the reinforcing projection 13. Therefore, the operability at the time of opening is improved.

  FIG. 5 is a schematic cross-sectional view showing a state in which the plastic containers shown in FIGS. 1 and 2 are stacked. As described above, the plastic container according to the present invention can be stacked and stored in the vertical direction, so that the storage property is good and the space can be effectively used at the time of storage, so that a certain amount of inventory is always required. It can be suitably used for various business purposes. The plastic container according to the present invention, when the contents are taken out, if the container is tilted and poured out, the contents stored in the shoulder portion 6 are not discharged due to its structure. It is necessary to install a spout with an extraction pipe reaching the bottom so that the contents remaining at the bottom can be pushed out and discharged at a pressure of.

  FIG. 6 is a cross-sectional explanatory view showing a method for recrystallization of the stopper portion of the plastic container according to the present invention for crystallization. A cylindrical heating device 10 is inserted into the stopper peripheral peripheral recess 7 so as to cover the stopper portion 2 of the plastic container from the outside, and the stopper portion 2 is heated from the outer periphery by a heating element 11 installed inside the heating device. . In the case where the material of the plug part 2 is a thermoplastic polyester resin such as polyethylene terephthalate resin or polyethylene naphthalate resin, the crystallinity is improved by reheating and slow cooling in this way, and as a result heat resistance Will improve. By doing in this way, it becomes possible to use also for the use which heats and uses the whole container.

  The material of the plastic container according to the present invention is not limited to the above-described thermoplastic polyester resin such as polyethylene terephthalate resin and polyethylene naphthalate resin, but also polyolefin resin such as polyethylene resin and polypropylene resin, and polyamide (nylon) system. A thermoplastic resin such as a resin can be used. These may be multilayered as necessary. These materials are determined in consideration of the properties of the contents, the required pressure resistance, heat resistance, and the like. Among these, polyethylene terephthalate resin is a resin having an excellent balance between cost and performance. A stretch blow molding method that uses polyethylene terephthalate resin to form a container body portion including a cap portion as a preform in advance by an injection molding method or the like, and heats the preform again to form a container body portion. Can be used to efficiently mold the container. In addition, as already described, it is possible to reheat and crystallize the plug portion to improve heat resistance.

It is also possible to mold the plastic container according to the present invention by an ordinary blow molding method. In addition to the extrusion blow molding using a normal single layer, a multilayer blow molding method using a barrier resin as an intermediate layer can also be used.
Hereinafter, the plastic container according to the present invention will be described more specifically based on examples.

  A preform having the shape shown in FIG. 8 was molded by an injection molding method using a polyethylene terephthalate resin (BK2180 manufactured by Nippon Unipet Co., Ltd.). This preform was reheated, and a plastic container having the shape shown in FIG. 3 was formed by a stretch blow molding method. The container has a diameter of 20 cm and a height of 20 cm. The plug part was reheated to 150 ° C. by a heating device, and gradually cooled to crystallize. This container was hot-filled with beverages such as tea to make a product for business use. Since these containers can be stacked and stored, they do not take a storage place and can be efficiently stored in a store with limited space. Moreover, since it can be accommodated in a dedicated heat retaining device and heated to 50 ° C. together with the container to provide warmer beverages such as tea in winter, it is highly convenient. By heating the container, the internal pressure of the container slightly increased, but no problem occurred.

DESCRIPTION OF SYMBOLS 1 ... Container main body 2 ... Mouth part 3 ... Cap 4 ... Bottom surface 5 ... Trunk part 6 ... Shoulder part 7 ... Mouth part periphery recessed part 8 ... Shoulder part Peripheral groove 9 ... Bottom peripheral projection 10 ... Heating device 11 ... Heating element 12 ... Mouth storage space 13 ... Reinforcement projection 14 ... Reinforcement rib 15 ... Underlay container 16 ··preform

Claims (6)

  A plastic container comprising a container body, a plug part and a cap screwed into the plug part. The container body has a bottom surface, a body part and a shoulder part, and the plug part is depressed from the shoulder part. A plastic container characterized in that a recess around the part is formed and a shoulder part forms the uppermost surface of the container.   A plastic container comprising a container body, a plug part and a cap screwed into the plug part. The container body has a bottom surface, a body part and a shoulder part, and the plug part is depressed from the shoulder part. A plastic container characterized in that a flat surface including a plurality of reinforcing protrusions provided on the shoulder portion forms a top surface of the container.   2. The plastic container according to claim 1, further comprising: a shoulder peripheral groove having a bottom peripheral protrusion on a peripheral edge of the bottom surface, and a shoulder peripheral groove having a shape in which the bottom peripheral protrusion is fitted on the peripheral edge of the shoulder.   3. The plastic container according to claim 2, wherein a bottom peripheral edge protrusion is provided on a peripheral edge of the bottom surface, and the bottom peripheral protrusion has a shape that fits into a reinforcing protrusion provided on a shoulder portion.   The plastic container according to any one of claims 1 to 4, wherein a reinforcing rib is provided on the bottom surface.   The material which comprises a stopper part is a thermoplastic polyester resin, and heat resistance was improved by reheating the stopper part and crystallizing, The any one of Claims 1-5 characterized by the above-mentioned. Plastic container.

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