JP7282465B2 - Synthetic resin container, synthetic resin container manufacturing method, and laminated preform - Google Patents

Description

The present disclosure relates to a synthetic resin container, a method for manufacturing a synthetic resin container, and a laminated preform.

2. Description of the Related Art As containers for containing liquids such as beverages, food seasonings, and cosmetics, synthetic resin containers formed into a bottle shape by blow-molding a preform and having a mouth portion and a body portion are widely used. ing.

In addition, by using a preform configured in a laminated structure by insert molding as such a synthetic resin container, a covering portion having functions such as decorativeness and gas barrier properties is formed on the outer surface of the body of the container body. Laminated laminated structures are known.

As a synthetic resin container in which a covering portion is laminated on the body portion of the container body, as shown in Patent Document 1, a label material is adhered to the outer peripheral surface of the container body in a peelable manner, and the label material is attached to the label main portion. and a band-shaped breakage portion that has low compatibility with the label main body and extends from one end to the other end in the axial direction of the label material. What is possible is disclosed.

Japanese Patent Application Laid-Open No. 2019-26339

By the way, in the synthetic resin container of Patent Document 1, it is necessary to form the breaking portion made of a material different from that of the main portion of the label. There was room for improvement in

An object of the present disclosure is to solve such problems, and the object thereof is to provide a synthetic resin container that can easily separate the coating from the container body while suppressing an increase in the cost of manufacturing equipment. An object of the present invention is to provide a method for manufacturing a container and a laminated preform.

The synthetic resin container of the present disclosure is
A synthetic resin container having a laminated structure formed by blow molding a laminated preform,
a bottle-shaped container body having a mouth and a body;
a covering portion stretched by blow molding together with the body portion and laminated on the outer surface of the body portion;
The covering portion is characterized by being made of a material containing polypropylene resin as a main material and adding 10% to 30% by weight of high-density polyethylene.

In the above configuration, the synthetic resin container of the present disclosure is integrally formed with the covering portion or formed as a part of the covering portion, and the covering portion is separated from the container body by a downward force acting. It is preferable to further provide an action portion that enables the peeling off.

In the synthetic resin container of the present disclosure, in the above configuration, the container body further includes a neck ring provided between the mouth portion and the body portion, and the acting portion is integrated with the covering portion. preferably formed and extending radially outwardly from a circumferential portion of the neck ring.

In the above configuration, the synthetic resin container of the present disclosure preferably further includes a ring portion that is integrally formed with the acting portion that is formed partially in the circumferential direction and that surrounds the entire circumference of the container body in the circumferential direction.

In the synthetic resin container of the present disclosure, in the configuration described above, it is preferable that the acting portion is formed as part of the covering portion and extends in the vertical direction.

In the synthetic resin container of the present disclosure, in the configuration described above, it is preferable that cutout portions extending in the vertical direction are formed in the covering portions located on both sides of the acting portion in the circumferential direction.

The manufacturing method of the synthetic resin container of the present disclosure includes:
A method for manufacturing a synthetic resin container having a laminated structure formed by blow molding a laminated preform, comprising:
forming an inner body of the laminate preform having a mouth and a body;
forming an outer body of the laminated preform covering the body portion of the inner body from the radially outer side;
stretching the body and the outer body of the inner body together by blow molding to form a container body and a covering;
The covering portion is characterized by being made of a material containing polypropylene resin as a main material and adding 10% to 30% by weight of high-density polyethylene.

The laminated preform of the present disclosure includes:
A laminated preform used for manufacturing a synthetic resin container having a laminated structure formed by blow molding,
an inner body having a mouth and a body;
an outer body covering the trunk portion of the inner body from the radially outer side,
The outer body is characterized by being formed of a material containing polypropylene resin as a main material and adding 10% to 30% by weight of high-density polyethylene.

Advantageous Effects of Invention According to the present disclosure, it is possible to provide a synthetic resin container, a synthetic resin container manufacturing method, and a laminated preform in which the covering portion can be easily separated from the container body while suppressing an increase in the cost of manufacturing equipment.

1 is a front half cross-sectional view of a synthetic resin container according to a first embodiment of the present disclosure; FIG. FIG. 2 is an enlarged front view showing an enlarged mouth portion and a neck ring portion of the synthetic resin container shown in FIG. 1; Fig. 2 is a plan view of the mouth and neck ring portion of the synthetic resin container according to the first embodiment of the present disclosure; 1 is a front half cross-sectional view of a laminated preform according to a first embodiment of the present disclosure; FIG. 4 is a flow chart showing each procedure of a method for manufacturing a synthetic resin container according to the first embodiment of the present disclosure; FIG. 5 is a plan view of the mouth and neck ring portion of the synthetic resin container according to the second embodiment of the present disclosure; FIG. 10 is a diagram showing a state in which the ring portion is pinched and the covering portion is about to be peeled off in the synthetic resin container according to the second embodiment of the present disclosure; Fig. 11 is an enlarged front view showing an enlarged opening and neck ring portion of a synthetic resin container according to a third embodiment of the present disclosure; FIG. 4 shows a test piece used for the trouser tear test. It is a figure which shows the outline of a structure of a trouser tear tester.

Hereinafter, the synthetic resin container 1 according to the first embodiment of the present disclosure will be illustrated in detail with reference to the drawings.

In the present specification and claims, the vertical direction means upward and downward directions when the synthetic resin container 1 is in an upright position as shown in FIG. Further, the radially inner side means the direction toward the inner side along a straight line that passes through the central axis O of the synthetic resin container 1 in FIG. shall mean the outward direction along a straight line perpendicular to the central axis O.

The synthetic resin container 1 of the present embodiment shown in FIG. 1 is formed into a laminated structure having a container body 10 and a covering portion 20 by blow molding a laminated preform 100 (see FIG. 4) which is an insert-molded product. It is what was done.

In this embodiment, the container body 10 is made of a synthetic resin mainly composed of polyethylene terephthalate resin (PET resin), and the covering part 20 is made of a synthetic resin mainly composed of polypropylene resin (PP resin). there is As the polypropylene-based resin, for example, J246M manufactured by Prime Polymer Co., Ltd. can be used.

The container body 10 is not limited to being made of polyethylene terephthalate resin, but may be made of other synthetic resin such as polyethylene naphthalate resin (PEN), PET-G resin, PCTG resin, PCTA resin, or the like. Moreover, it is preferable that the covering portion 20 is made of a material mainly composed of a polypropylene-based resin to which 10% to 30% by weight of high-density polyethylene (HDPE) is added. In this embodiment, the covering portion 20 uses a material to which 10% by weight of high-density polyethylene is added. As will be described later, the covering part 20 is laminated so as to be peeled off from the container body 10, and a material having functions such as decorativeness, light barrier properties, oxygen barrier properties, and water vapor barrier properties can be used. .

The container body 10 has a bottle shape with a mouth portion 11 and a body portion 12 . The inside of the container main body 10 is a storage space S, and liquids such as beverages, food seasonings, and cosmetics can be stored in the storage space S as contents.

The mouth portion 11 has a substantially cylindrical shape and constitutes a discharge port for the contents accommodated in the accommodation space S. A male screw 11a is integrally provided on the outer peripheral surface of the mouth portion 11 for attaching a cap (not shown) for closing the mouth portion 11 by screwing.

In addition, the opening 11 may be configured to have an annular protrusion for attaching the cap by plugging instead of the screw connection.

The trunk portion 12 is integrally connected to the lower end portion of the mouth portion 11, and has a neck-like portion 12a whose diameter gradually expands downward. It has a shoulder portion 12b, a substantially cylindrical body portion 12c integrally connected to the lower end of the shoulder portion 12b and extending downward with the same diameter, and a bottom portion 12d closing the lower end of the body portion 12c. .

The shape of the trunk portion 12 can be changed in various ways, for example, without the neck portion 12a.

A neck ring 13 is integrally provided between the mouth portion 11 and the body portion 12 of the container body 10 . The neck ring 13 protrudes radially outward from the upper end portions of the mouth portion 11 and the body portion 12 and has a substantially plate shape extending around the central axis O over the entire circumference. As shown in FIG. 2, the lower surface 13a of the neck ring 13 facing the trunk portion 12 side is a plane substantially perpendicular to the central axis O, and the upper surface 13b of the neck ring 13 facing the mouth portion 11 side is It forms an inclined surface that inclines so as to approach the body portion 12 as it goes radially outward.

An annular projection 14 projecting radially outward is integrally formed between the external thread 11 a and the neck ring 13 on the outer peripheral surface of the mouth portion 11 . The annular protrusion 14 is a portion to which a strip-like portion provided on the cap, which is breakable to prevent tampering with the cap attached to the mouth portion 11, is locked.

As shown in FIG. 1 , the covering portion 20 is laminated on the outer surface of the body portion 12 of the container body 10 to cover the entire body portion 12 . The thickness of the covering portion 20 is thinner than the thickness of the trunk portion 12 .

In this embodiment, the upper end portion of the covering portion 20 constitutes a flange 21 . The flange 21 extends radially outward from the upper end portion of the covering portion 20 and has a substantially plate-like shape extending along the entire circumference around the central axis O, and is in close contact with the lower surface 13 a of the neck ring 13 . . In the illustrated case, the outer diameter of the flange 21 is substantially the same as the outer diameter of the neck ring 13, but the outer diameter of the flange 21 may be smaller than the outer diameter of the neck ring 13. It may be larger than the outer diameter.

As shown in FIGS. 2 and 3, an action portion 15 is formed on the outer peripheral surface of the neck ring 13 so as to extend radially outward from one circumferential location. The action portion 15 is integrally formed with the flange 21 and protrudes radially outward from the outer peripheral end of the flange 21 . That is, the acting portion 15 is provided integrally with the covering portion 20 . In the example of FIG. 2 , the lower surface of the working portion 15 is substantially the same height as the lower surface of the flange 21 , and the working portion 15 is formed thicker than the flange 21 . In this embodiment, as shown in FIG. 3, the acting portion 15 extends radially outward with the same width, and has an R shape so that the tip can be easily picked.

As shown in FIG. 2, notch portions 16 extending downward from the action portion 15 are provided on the covering portions 20 positioned on both sides of the action portion 15 in the circumferential direction. The notch portion 16 is formed by cutting out the covering portion 20 in the region, and a part of the trunk portion 12 of the container body 10 is exposed to the outside. The notch portion 16 has a width that gradually decreases downward from positions on both sides in the circumferential direction of the radially inner end of the action portion 15, and has an R-shaped lower end portion. When the user grabs the working portion 15 and pulls it down, a shearing force acts on the lower end of the notch portion 16, causing the cutout portion 16 to be further torn downward, and the cover portion 20 is torn at one point in the circumferential direction to the bottom portion 12d. It can be peeled off in strips. Then, the user can peel off the covering portion 20 in the circumferential direction as well, starting from the covering portion 20 that has been peeled off in the form of a strip. Thus, after using the contents, the user can peel off the cover part 20 from the container body 10 by a simple operation of picking up the action part 15 and pulling it downward. Therefore, the covering portion 20 made of a synthetic resin mainly composed of a synthetic resin material different from that of the container body 10 can be easily peeled off from the container body 10 for separate disposal.

In particular, in this embodiment, as the material of the covering portion 20, a material mainly composed of a polypropylene-based resin and to which 10% by weight of high-density polyethylene is added is used. Such a configuration reduces the tearing force that tears the covering portion 20 when the user picks up the action portion 15 and peels off the covering portion 20 downward. In addition, the rectilinearity of the tear portion extending downward from the notch portion 16 is improved. It is considered that this is because the polypropylene resin and the high-density polyethylene are difficult to mix, and the high-density polyethylene is sandwiched between the spherulites of the polypropylene, thereby reducing the tearing force and improving the straightness of the tearing portion.

A synthetic resin container 1 shown in FIG. 1 is formed by blow-molding a laminated preform 100, which is an insert-molded product. FIG. 4 shows an example of a laminated preform 100 for forming the synthetic resin container 1 according to this embodiment.

A laminated preform 100 shown in FIG. 4 is formed into a laminated structure including an inner body 110 and an outer body 120 by insert molding.

An inner body 110 corresponding to the container body 10 is made of polyethylene terephthalate resin and has a mouth portion 111 and a body portion 112 .

The mouth portion 111 has a substantially cylindrical shape, and a male thread 111a is integrally provided on the outer peripheral surface thereof. On the other hand, the body portion 112 has a bottomed cylindrical shape with an outer diameter substantially equal to that of the mouth portion 111 and a thickness greater than that of the mouth portion 111 , and is integrally connected to the lower end of the mouth portion 111 .

A neck ring 113 is integrally provided between the mouth portion 111 and the body portion 112 . The neck ring 113 protrudes radially outward from the upper end portions of the mouth portion 111 and the body portion 112 and has a substantially plate shape extending around the central axis O over the entire circumference. A lower surface 113a of the neck ring 113 facing the trunk portion 112 side is a plane substantially perpendicular to the central axis O, and an upper surface 113b of the neck ring 113 facing the mouth portion 111 side faces radially outward. It becomes an inclined surface which inclines so that it may approach the trunk|drum 112 along with it.

The outer body 120, which is the part corresponding to the covering part 20, is mainly made of polypropylene-based resin, and is formed in a bottomed cylindrical shape from a synthetic resin to which 10% by weight of high-density polyethylene is added. It is laminated on the side surface and covers the entire outer surface. The thickness of the cylindrical side surface of the outer body 120 is configured to be thinner than the thickness of the trunk portion 112, and can be in the range of 1.0 mm to 1.5 mm, for example. In this embodiment, when the side surface of the outer body 120 has the thickness described above, the manufacturing control is performed so that the thickness of the covering portion 20 is in the range of 60 μm or more and 180 μm or less. The relationship between the thicknesses of the outer body 120 and the covering portion 20 depends on the manufacturing conditions such as the draw ratio during blow molding.

A flange 121 is integrally provided at the upper end of the outer body 120 . The flange 121 extends radially outward from the upper end of the outer body 120 and has a substantially plate shape extending around the central axis O over the entire circumference, and is in close contact with the lower surface 113 a of the neck ring 113 . By providing the flange 121 on the outer body 120, for example, when stretch-blow molding the laminated preform 100, the lower surface 113a of the neck ring 113 is abutted against the reference plane of the blow molding die while sandwiching the flange 121. Fixing produces the effect of pseudo-bonding the flange 121 and the neck ring 113 . Therefore, when the laminated preform 100 is stretch blow molded, the tensile force applied to the outer body 120 can be held by the flange 121, so that the outer body 120 is misaligned with respect to the inner body 110, resulting in poor stretching. can be suppressed.

Here, the mouth portion 111 of the inner body 110 of the laminated preform 100 and the neck ring 113 are portions that are not stretched by blow molding, and the flange 121 and the working portion 115 of the laminated preform 100 are also portions that are not stretched by blow molding. is. Therefore, the shapes of the mouth portion 111 and the neck ring 113 of the laminated preform 100 are substantially the same as the shapes of the mouth portion 11 and the neck ring 13 of the container body 10 of the synthetic resin container 1, respectively. The shape of the flange 121 and the action portion 115 of the reform 100 is substantially the same as the shape of the flange 21 and the action portion 15 of the covering portion 20 of the synthetic resin container 1 .

That is, as shown in FIG. 4 , an acting portion 115 is formed radially outward from one circumferential location on the outer peripheral surface of the neck ring 113 . The acting portion 115 is integrally formed with the flange 121 and protrudes radially outward from the outer peripheral end of the flange 121 . The acting portion 115 is provided integrally with the outer body 120 . By applying a downward force to the acting portion 115, the outer body 120 can be pulled downward. In the example of FIG. 4 , the lower surface of the action portion 115 is approximately the same height as the lower surface of the flange 121 , and the action portion 115 is formed thicker than the flange 121 . In this embodiment, the acting portion 115 extends radially outward with the same width, and has an R-shaped tip so that it can be easily picked.

Cutout portions 116 extending downward from the action portion 115 are provided on the outer body 120 positioned on both sides of the action portion 115 in the circumferential direction, as shown in FIG. The notch portion 116 is formed by cutting out the outer body 120 in this region and exposing a portion of the trunk portion 112 of the inner body 110 to the outside. The notch portion 116 has a width that gradually decreases downward from positions on both sides in the circumferential direction of the radially inner end of the action portion 115, and has an R-shaped lower end portion.

The trunk portion 112 of the laminated preform 100 is a portion that is stretched by blow molding and formed into the trunk portion 12 of the container body 10 . Further, the outer body 120 of the laminated preform 100 is a portion formed in the covering portion 20 that is stretched together with the body portion 112 by blow molding and laminated on the outer surface of the body portion 12 .

The laminated preform 100 having the above configuration is an insert-molded product formed by insert molding in this embodiment. For example, the laminated preform 100 can be formed by insert molding (injection molding) by inserting the inner body 110 formed by injection molding in advance, or insert molding by inserting the outer body 120 formed by injection molding in advance. It can be formed by (injection molding). In the laminated preform 100, after the inner body 110 or the outer body 120 is formed by injection molding, the outer body 120 or the inner body 110 may be molded by two-color molding.

Next, a method for manufacturing the synthetic resin container 1 according to the first embodiment of the present disclosure will be described.

FIG. 5 is a flow chart showing the procedure for carrying out the method for manufacturing the synthetic resin container 1 according to this embodiment. When manufacturing the laminated preform 100 as the precursor of the synthetic resin container 1, first, the inner body 110 shown in FIG. 4 is molded by injection molding or the like (step S101). The inner body 110 has a mouth portion 111, a body portion 112, and a neck ring 113 provided between the mouth portion 111 and the body portion 112, as shown in FIG.

Next, the inner body 110 molded in step S101 is placed in the cavity of the mold (step S102). The mold here is a mold for molding the outer body 120, and it is assumed that the laminate preform 100 is insert-molded using the inner body 110 as an insert material.

On the other hand, in parallel with steps S101 and S102, the outer body resin is prepared (step S103). In this embodiment, the outer body resin is produced by adding 10% by weight of high density polyethylene (HDPE) to the polypropylene resin.

Next, the synthetic resin for the outer body 120 produced in step S103 is injected into the space between the cavity and the inner body 110 formed in step S102 to mold the outer body 120 (step S104). When molding the outer body 120 , the acting portion 115 projecting radially outward from the flange 121 is also integrally formed with the outer body 120 . After step S104, the molding of the laminated preform 100 is completed by releasing the laminated preform 100 from the mold.

Note that the formation of the laminated preform 100 is not limited to insert molding the laminated preform 100 using the inner body 110 as an insert material, and the outer body 120 is molded first and then laminated using the outer body 120 as an insert material. The preform 100 may be insert molded. Alternatively, after the inner body 110 or the outer body 120 is injection molded, the outer body 120 or the inner body 110 may be formed by two-color molding.

In order to manufacture the synthetic resin container 1 from the laminated preform 100, the neck ring 113 of the laminated preform 100 formed in step S104 is abutted against the reference surface of the blow molding die and fixed, and the laminated preform is formed. 100 is stretch blow molded (step S105). By this stretch blow molding, the outer body 120 is stretched together with the body portion 112 of the inner body 110 to form the body portion 12 of the synthetic resin container 1 . On the other hand, mouth portion 111 , neck ring 113 , flange 121 , working portion 115 , etc. are not stretched by blow molding and maintain substantially the same shape as laminated preform 100 . The production of the synthetic resin container 1 is completed by stretch blow molding the laminated preform 100 .

As described above, the present embodiment is a synthetic resin container 1 having a laminated structure formed by blow molding a laminated preform 100, which is a bottle-shaped container having a mouth portion 11 and a body portion 12. It comprises a main body 10 and a cover portion 20 which is stretched by blow molding together with the body portion 12 and laminated on the outer surface of the body portion 12. The cover portion 20 is mainly made of polypropylene resin and 10% by weight of high-density polyethylene. It was configured to be formed of a material added 30% by weight from By adopting such a configuration, when the user tears the covering portion 20 downward, the straightness of the tearing portion can be improved, and the tearing force can be reduced.

Moreover, in this embodiment, the covering portion 20 is configured to have a thickness of 60 μm or more and 180 μm or less. By adopting such a configuration, the user can relatively easily tear the covering part 20 and separate it from the container body 10 by keeping the tearing force within an appropriate range while maintaining the good appearance of the covering part 20 . be able to.

Further, in the present embodiment, it is formed integrally with the covering portion 20 or formed as a part of the covering portion 20, and the covering portion 20 can be peeled off from the container body 10 by applying a downward force. It is configured so as to further include an action portion 15 for performing. By adopting such a configuration, the user can pick up the working portion 15 and pull it downward, thereby peeling off the covering portion 20 downward at the circumferential position where the working portion 15 is formed. Thus, after using the contents, the user can peel off the cover part 20 from the container body 10 by a simple operation of picking up the action part 15 and pulling it downward. Therefore, the covering portion 20 made of a synthetic resin mainly composed of a synthetic resin material different from that of the container body 10 can be easily peeled off from the container body 10 for separate disposal.

In addition, in this embodiment, the container body 10 further includes a neck ring 13 provided between the mouth portion 11 and the body portion 12, and the acting portion 15 is integrally formed with the covering portion 20, and the neck ring 13 so as to extend radially outward from a portion of the circumferential direction. By adopting such a configuration, the user can more easily grasp and pull down the action portion 15 extending radially outward.

Further, in the present embodiment, the notch portions 16 extending in the vertical direction are formed in the covering portions 20 positioned on both sides of the action portion 15 in the circumferential direction. By adopting such a configuration, when the user grabs the action portion 15 and pulls it down, a shearing force acts on the lower end of the notch portion 16, and the cover portion 20 is torn further downward. One point in the direction can be peeled off in a strip shape up to the bottom portion 12d. Then, the user can peel off the covering portion 20 also in the circumferential direction, starting from the covering portion 20 removed in the strip shape. Thus, after using the contents, the user can peel off the cover part 20 from the container body 10 by a simple operation of picking up the action part 15 and pulling it downward. Therefore, the covering portion 20 made of a synthetic resin mainly composed of a synthetic resin material different from that of the container body 10 can be easily peeled off from the container body 10 for separate disposal.

Further, the present embodiment is a method for manufacturing a synthetic resin container 1 having a laminated structure formed by blow molding a laminated preform 100. The laminated preform 100 has a mouth portion 111 and a body portion 112. forming an inner body 110 of the inner body 110; forming an outer body 120 of the laminated preform 100 that covers the body portion 112 of the inner body 110 from the radial outside; Both are stretched by blow molding to form the container body 10 and the covering part 20, and the covering part 20 is made of a material in which 10% to 30% by weight of high-density polyethylene is added to polypropylene resin as the main material. configured to be formed. By adopting such a configuration, when the user tears the covering portion 20 downward, the straightness of the tearing portion can be improved, and the tearing force can be reduced.

Further, the present embodiment is a laminated preform 100 used for manufacturing a synthetic resin container 1 having a laminated structure formed by blow molding, which comprises an inner body 110 having a mouth portion 111 and a body portion 112, It comprises an outer body 120 that covers the body portion 112 of the inner body 110 from the outside in the radial direction, and the outer body 120 is made of polypropylene-based resin as the main material and 10% to 30% by weight of high-density polyethylene added thereto. configured as By adopting such a configuration, after the laminated preform 100 is blow-molded to manufacture the synthetic resin container 1, when the user tears the covering portion 20 downward, the straightness of the tearing portion can be improved. , the tearing force can be reduced.

Next, the synthetic resin container 2 according to the second embodiment of the present disclosure will be illustrated in detail.

The synthetic resin container 2 according to the present embodiment has a configuration similar to that according to the first embodiment, except that a ring portion 18 is formed around the neck ring 13. . Therefore, the differences from the first embodiment will be mainly described here. Also, parts having configurations corresponding to those of the first embodiment will be described with the same reference numerals.

As shown in FIG. 6, the synthetic resin container 2 according to this embodiment has a ring portion 18 that surrounds the neck ring 13 from the outside in the radial direction. In the present embodiment, the ring portion 18 is integrally formed with the flange 21 at approximately the same height as the flange 21 (see FIG. 7), and is connected to the outer peripheral end of the flange 21 at three locations in the circumferential direction by broken portions 18a. there is That is, the ring portion 18 is integrally formed with the action portion 15 and the covering portion 20 and is configured to surround the entire circumference of the container body 10 in the circumferential direction.

The user pinches the circumferential position of the ring portion 18 facing the action portion 15 and, while tearing off the fracture portion 18a, folds the ring portion 18 toward the action portion 15 with the action portion 15 as a fulcrum, as shown in FIG. . By gripping the ring portion 18 and pulling it further downward, the user can peel off one portion of the covering portion 20 in the circumferential direction through the action portion 15 to the bottom portion 12d in a strip shape. . In particular, in this embodiment, as the material of the covering portion 20, a material mainly composed of polypropylene resin and containing 10% by weight of high-density polyethylene is used. When tearing downward, the straightness of the tearing portion can be improved, and the tearing force can be reduced. Then, the user can peel off the covering portion 20 also in the circumferential direction, starting from the covering portion 20 removed in the strip shape. As a result, after using the contents, the user can peel off the covering part 20 from the container body 10 by a simple operation of grasping the ring part 18 and pulling it downward. In particular, in this embodiment, since the covering portion 20 can be peeled off while pinching the ring portion 18 having a size surrounding the container body 10, a force sufficient to peel off the covering portion 20 can be easily applied to the covering portion 20. can be made Therefore, the covering portion 20 made of a synthetic resin mainly composed of a synthetic resin material different from that of the container body 10 can be easily peeled off from the container body 10 for separate disposal. In addition, in this embodiment, since the user picks up the ring portion 18 and pulls it down, it is not necessary to apply force directly to the action portion 15 . Therefore, the acting portion 15 does not necessarily have to protrude radially outward from the outer peripheral portion of the flange 21 as shown in FIGS. It suffices to have a size that enables strong connection.

Next, the synthetic resin container 3 according to the third embodiment of the present disclosure will be illustrated in detail.

The synthetic resin container 3 according to the present embodiment has a configuration similar to that of the first embodiment, except that the position of the action portion 15 is changed. Therefore, the differences from the first embodiment will be mainly described here. Also, parts having configurations corresponding to those of the first embodiment will be described with the same reference numerals.

As shown in FIG. 8, the synthetic resin container 3 according to the present embodiment has an action portion 19 formed as a part of the covering portion 20, and along the trunk portion 12 (see FIG. 1) of the container body 10, It extends vertically. In addition, vertically extending notch portions 19a are provided on both circumferential sides of the action portion 19 . That is, as shown in FIG. 8, in the region directly below the neck ring 13 in the covering portion 20, two cutout portions 19a without the covering portion 20 are provided in the circumferential direction. By connecting them together, an action portion 19 that protrudes upward along the trunk portion 12 is formed in a region between the notch portions 19a.

The user pulls the upper end portion of the action portion 19 extending in the vertical direction and protruding upward from the body portion 12 of the container body 10 to the radially outer side, picks it up, and pulls it down to extend the covering portion 20 in the circumferential direction. , can be stripped off in a band-like manner up to the bottom portion 12d. In particular, in the present embodiment, as the material of the covering portion 20, a material mainly composed of polypropylene-based resin and 10% by weight of high-density polyethylene is used. When tearing downward, the straightness of the tearing portion can be improved, and the tearing force can be reduced. Then, the user can peel off the covering portion 20 in the circumferential direction as well, starting from the covering portion 20 that has been peeled off in the form of a strip. Thus, after using the contents, the user can peel off the cover part 20 from the container body 10 by a simple operation of picking up the action part 19 and pulling it downward. In particular, in the present embodiment, the acting portion 19 does not protrude radially outward from the neck ring 13, and is provided as a part of the covering portion 20 along the body portion 12 of the container body 10. It does not impair the appearance of 3 and ease of use during use.

The laminated preform used for manufacturing the synthetic resin container 3 according to the present embodiment has an action portion formed as a part of the outer body, similarly to the synthetic resin container 3 .

Although the present disclosure has been described with reference to figures and examples, it should be noted that various variations and modifications will be readily apparent to those skilled in the art based on the present disclosure. Therefore, it should be noted that these variations and modifications are included in the scope of the present invention. For example, the functions included in each component can be rearranged so as not to be logically inconsistent, and multiple components can be combined into one or divided. It should be understood that the scope of the present invention includes these.

For example, in the above-described embodiment, the covering portion 20 is made of a material in which 10% to 30% by weight of high-density polyethylene is added to a polypropylene-based resin as a main material. In order to improve functions such as barrier properties or water vapor barrier properties, a resin other than high-density polyethylene may be further added.

Further, in the above-described embodiment, the action portions 15 and 19 are provided only at one position in the circumferential direction, but the present invention is not limited to this aspect. The acting portions 15 and 19 may be provided at a plurality of locations in the circumferential direction.

Further, in the above-described embodiment, the covering portion 20 is configured to cover the entire body portion 12 of the container body 10, but the present invention is not limited to this aspect. The covering portion 20 may be configured to cover, for example, a region of the trunk portion 12 of the container body 10 other than the bottom portion 12d.

Further, in the first embodiment and the second embodiment, the acting portion 15 is configured to extend in a direction orthogonal to the central axis O and directed radially outward, but the present invention is not limited to this aspect. The action portion 15 may be inclined, for example, in the vertical direction with respect to the direction perpendicular to the central axis O and extending radially outward.

In the above-described embodiment, the upper end of the covering portion 20 constitutes the flange 21, but it is not limited to this aspect. 13 may be configured to extend to the lower surface 13a of the lower surface 13a.

Further, in the first embodiment and the second embodiment, the cutout portions 16 are provided on both sides of the action portion 15 in the circumferential direction, but the present invention is not limited to this aspect. The notch portion 16 may be provided only on one side of the action portion 15 in the circumferential direction, or may not be provided.

Further, in the second embodiment, the ring portion 18 is configured to be connected to the flange 21 by the breaking portion 18a, but the present invention is not limited to this aspect, and the ring portion 18 is connected to the covering portion 20 only through the action portion 15. may be configured to be connected to This eliminates the need to cut off the ring portion 18 .

As the materials used for the covering portion 20, six types of materials shown in Table 1 were compared for tearability. In Table 1, polypropylene (PP) as a base resin is polypropylene (J246M) manufactured by Prime Polymer Co., Ltd., and additive resins include HDPE (high density polyethylene), LDPE (low density polyethylene), LLDPE (linear low density polyethylene), COC (cycloolefin polymer) and GPPS (general purpose polystyrene) were added at 10% by weight. The tearability was evaluated by tearing the test piece shown in FIG. 9 using the trouser tear tester shown in FIG. In FIG. 9, the longitudinal direction of the test piece is the MD (machine direction) direction, that is, the resin flow direction during molding. This test is based on JIS K7128-1:1998, but the tear speed is 1000mm/min. was carried out under the conditions of Each specimen has a thickness of 0.16 mm.

Comparing the tearability of the resins, in the PP with no added resin, the straightness of the tearing portion was poor, resulting in the tearing portion deviating greatly in the lateral direction of the test piece in FIG. % added, the tearing part extended along the longitudinal direction of the test piece, exhibiting good straightness, and the tearing force could be reduced. In the case of using an additive resin other than HDPE, no significant effect was obtained in either the linearity of the tearing portion or the tearing force compared to the case without the additive resin. It is considered that this is because the polypropylene-based resin and the high-density polyethylene are difficult to mix, and the high-density polyethylene is sandwiched between the spherulites of the polypropylene, reducing the tearing force and improving the straightness of the tearing portion.

Next, tear resistance was evaluated by changing the amount of HDPE added. Each specimen has a thickness of 0.18 mm. Table 2 shows the evaluation results.

When the amount of HDPE added was increased by 10% by weight from no addition to 50% by weight, tearing force in the MD (machine direction) direction (resin flow direction) was observed at 10% by weight and 20% by weight of HDPE added. was reduced or remained the same, resulting in a smaller "MD tear force/TD tear force" ratio (where TD is the transverse direction). When the ratio of "tearing force in the MD direction/tearing force in the TD direction" becomes small, it is possible to suppress deviation of the tearing portion in the TD direction, thereby improving straightness of the tearing portion. Therefore, by setting the amount of HDPE added in the range of 10% to 20% by weight and determining the direction of the resin so that the MD direction is the vertical direction of the container, the tearing portion when tearing the covering portion 20 in the downward direction can improve sexuality. Moreover, when the amount of HDPE added is 10% by weight, the tearing force when tearing the covering portion 20 downward can be reduced. When the amount of HDPE added was 30% by weight, although the MD direction tearing force increased slightly, the ratio of "MD direction tearing force/TD direction tearing force" was kept small, and straightness of the tear portion was improved. A clear increase in MD tear force was observed at 40 wt% HDPE loading. With 50% by weight of HDPE, the covering part 20 sometimes broke during blow molding.

Reference Signs List 1, 2, 3 synthetic resin container 10 container body 11 mouth portion 11a male screw 12 body portion 12a neck portion 12b shoulder portion 12c body portion 12d bottom portion 13 neck ring 13a lower surface 13b upper surface 14 annular projection 15 acting portion 16 notch Part 18 Ring part 18a Breaking part 19 Acting part 19a Notch part 20 Covering part 21 Flange 100 Laminated preform 110 Internal body 111 Mouth part 111a Male screw 112 Body part 113 Neck ring 113a Lower surface 113b Upper surface 115 Acting part 116 Notch part 120 Outside Body 121 Flange O Center axis S Accommodating space

Claims (8)

A synthetic resin container having a laminated structure formed by blow molding a laminated preform,
a bottle-shaped container body having a mouth and a body;
a covering portion stretched by blow molding together with the body portion and laminated on the outer surface of the body portion;
A container made of synthetic resin, wherein the covering part is made of a material containing a polypropylene resin as a main material and adding 10% to 30% by weight of high-density polyethylene. Further comprising an action part integrally formed with the covering part or formed as part of the covering part, and capable of peeling off the covering part from the container body by applying a downward force, The synthetic resin container according to claim 1. The container body further comprises a neck ring provided between the mouth and the body,
3. The synthetic resin container according to claim 2, wherein the acting portion is integrally formed with the covering portion and extends radially outward from a portion of the neck ring in the circumferential direction. 4. The synthetic resin container according to claim 2, further comprising a ring portion integrally formed with said action portion formed in a part of said container body in the circumferential direction and surrounding the entire circumference of said container body in the circumferential direction. 3. The synthetic resin container according to claim 2, wherein said acting portion is formed as part of said covering portion and extends vertically. The synthetic resin container according to any one of claims 2 to 5, wherein vertically extending notch portions are formed in the covering portions located on both sides in the circumferential direction of the acting portion. A method for manufacturing a synthetic resin container having a laminated structure formed by blow molding a laminated preform, comprising:
forming an inner body of the laminate preform having a mouth and a body;
forming an outer body of the laminated preform covering the body portion of the inner body from the radially outer side;
stretching the body and the outer body of the inner body together by blow molding to form a container body and a covering;
A method for manufacturing a synthetic resin container, wherein the covering portion is made of a material containing a polypropylene resin as a main material and 10% to 30% by weight of high-density polyethylene added thereto. A laminated preform used for manufacturing a synthetic resin container having a laminated structure formed by blow molding,
an inner body having a mouth and a body;
an outer body covering the trunk portion of the inner body from the radially outer side,
A laminated preform, wherein the outer body is made of a material containing a polypropylene-based resin as a main material and 10 to 30% by weight of high-density polyethylene added thereto.

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