Extrusion blow container

Abstract

To reduce environmental loads, and prevent deterioration and degradation of a biomass-blended resin layer.SOLUTION: An extrusion blow container 1 includes a bottomed cylindrical container body 2 storing a content, and a tearing-off part 3 which is integrally molded with a mouth part 10 of the container body through a breakable weakened part 30, and closes the mouth part of the container body, wherein the whole container body includes an outer layer 20 formed of a first synthetic resin, a biomass-blended resin layer 21 which is formed of a biomass-blended resin containing a biomass material and a second synthetic resin, and is arranged on an inner side in a radial direction of the container body with respect to the outer layer, and an inner layer 22 which is formed of a third synthetic resin, and is arranged on an inner side in the radial direction of the container body with respect to the biomass-blended resin layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to extrusion blown containers. [Background technology]

[0002] Extrusion-blow molded containers made of synthetic resin, each having a mouth, a body, and a bottom, are known. In recent years, in the field of products using synthetic resin, including this type of extrusion-blow molded container, there has been a demand for a reduction in the amount of synthetic resin used, from the perspective of reducing environmental impact. To meet this need, for example, extrusion-blow molded containers are known that are molded using a paper-blended resin layer (biomass-blended resin layer) (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7455484 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the case of the extrusion blow container described in Patent Document 1, after extrusion blow molding, burrs are removed and finishing processing, such as heat cutting, may be performed to ensure that the upper opening edge of the mouth is a clean, flat surface. However, because the entire product, including the mouth, is formed using the paper-blended resin layer, the paper-blended resin layer is exposed at the upper opening edge of the mouth, and therefore, there remains a problem that the paper component (biomass material) in the exposed paper-blended resin layer burns due to the influence of heat during heat cutting, causing problems such as alteration or deterioration of the paper-blended resin layer.

[0005] Furthermore, in order to protect the upper edge of the opening of the mouth, it is conceivable to heat seal the opening of the mouth with a sealing material such as an aluminum seal, but even in this case, there is a risk of problems such as the paper-blended resin layer being altered or deteriorated due to the influence of heat, and there is also a risk of the seal (adhesion) being insufficient due to the influence of the paper components.

[0006] The present invention was made in consideration of these circumstances, and its purpose is to provide an extrusion blown container that can reduce the environmental impact and prevent the biomass-blended resin layer from changing or deteriorating. [Means for solving the problem]

[0007] (1) The extrusion blow container of the present invention comprises a bottomed cylindrical container body for accommodating contents, and a tear-off part that is integrally molded with the mouth of the container body via a breakable weakened part and closes the mouth of the container body. The entire container body has a laminated structure comprising an outer layer formed of a first synthetic resin, a biomass-blended resin layer formed of a biomass-blended resin containing a biomass material and a second synthetic resin and arranged radially inward of the container body relative to the outer layer, and an inner layer formed of a third synthetic resin and arranged radially inward of the container body relative to the biomass-blended resin layer.

[0008] According to the extrusion-blown container of the present invention, the entire container body, including the mouth, can have a three-layer laminate structure consisting of an outer layer, a biomass-blended resin layer, and an inner layer. In particular, the biomass-blended resin layer, which is an intermediate layer disposed between the outer layer and the inner layer, is formed from a biomass-blended resin containing biomass material. Therefore, by utilizing biomass material, the amount of synthetic resin used can be reduced, and CO2 emissions can also be reduced. This can contribute to reducing the environmental impact. Furthermore, because the mouth and grip part of the container body are integrally formed by extrusion blow molding, there is no need for conventional finishing processes such as heat cutting on the upper opening edge of the mouth of the container body or heat sealing a sealing material after molding. This prevents the biomass material from burning due to heat. This prevents the biomass-blended resin layer from changing or deteriorating, resulting in an extrusion blow container with the proper quality and rigidity of the container body.

[0009] When using an unused container, the user can apply external force to the gripping part with a fingertip or other object, tearing the weakened portion and removing the gripping part from the opening of the container body, thereby opening the opening of the container body and allowing the contents to be used.

[0010] Furthermore, since the container body has an outer layer and an inner layer made of synthetic resin with a biomass-blended resin layer sandwiched therebetween, for example, after extrusion blow molding, the inner layers can be joined together at the bottom of the container body, for example, while heating the outer layer. This makes it possible to form the container body into a tubular shape with a collapsed bottom. In this case, for example, the inner layers can be heat-sealed while protecting the ends of the biomass-blended resin layer using the outer or inner layer, so there is no need to directly heat the biomass-blended resin layer. Therefore, even in this case, scorching of the biomass material can be suppressed, and alteration or deterioration of the biomass-blended resin layer can be prevented.

[0011] (2) The biomass material may contain a paper component as a main component.

[0012] In this case, since the main component is paper, the biomass material can be made inexpensive, which makes it easier to reduce the manufacturing costs of the extrusion blown container.

[0013] (3) The ratio of the biomass material contained in the biomass-blended resin may be 30% by weight or less.

[0014] In this case, the proportion of biomass materials such as paper components in the biomass-blended resin is kept to 30% by weight or less, which prevents excessive biomass material from being included while reducing the amount of synthetic resin used. Therefore, when the heated and melted biomass-blended resin is injected to form, for example, a parison during extrusion blow molding, it is possible to prevent the biomass material from burning and causing deterioration or degradation of the biomass-blended resin.

[0015] (4) The biomass-blended resin layer may be formed from a blend resin of the biomass-blended resin and an olefin-based resin.

[0016] In this case, since the biomass-blended resin layer contains a flexible olefin-based resin, uneven circumferential stretching can be suppressed. Therefore, the container body can be easily molded into the desired shape. Furthermore, since the olefin-based resin has the property of being easily molded at low temperatures, the biomass material is even less likely to burn during extrusion blow molding.

[0017] (5) The tear-off portion is arranged coaxially with the container axis and is connected to the upper opening edge of the mouth of the container body via the weakened portion around the entire circumference, and comprises a topped cylindrical tear-off cap that closes the mouth of the container body from above, and a pair of tear-off pieces that protrude from the tear-off cap radially outward from the container body and are arranged on either side of the container axis, and the weakened portion may be made to easily break as the tear-off cap rotates around the container axis.

[0018] In this case, when opening the mouth of the container body, the entire tear section can be rotated using the pair of tear pieces with the fingertips, which applies stress evenly and efficiently to the weakened section, allowing the weakened section to be smoothly broken along the entire circumference of the mouth of the container body and allowing the tear cap to be removed from the mouth of the container body. In particular, because the entire tear-off part can be removed while rotating around the axis of the container, stress transmitted from the tear-off part to the opening when removing the tear-off part can be prevented from concentrating on, for example, the shoulder or a portion of the body of the container body. If stress were to concentrate on the shoulder or a portion of the body of the container body, it could potentially cause the container body to bend or dent. Therefore, by removing the gripping portion while rotating the container around its axis, the opening of the container body can be opened without causing bending or denting of the container body.

[0019] (6) An extrusion-blow container, wherein each of the pair of tear pieces has a finger-hook recess formed therein, recessed in a circumferential direction around the axis of the container.

[0020] In this case, the tearing part can be rotated around the axis of the container while the fingertip is hooked in the finger hook recess, which allows for efficient application of stress to the tearing part and improves operability.

[0021] (7) At least one pair of the tear pieces of the tearing portion may have a multilayer structure in which a laminate formed by stacking the outer layer, the biomass-blended resin layer, and the inner layer is pressed together with the inner layers overlapping each other.

[0022] In this case, at least one pair of tear tabs in the tear section has a multilayer structure in which two laminates, each consisting of an outer layer, a biomass-blended resin layer, and an inner layer, are stacked together. Specifically, the pair of tear tabs has a multilayer structure formed by crimping the laminates together with their respective inner layers stacked together. This allows the tear tabs to have a predetermined thickness and ensure rigidity, improving the ease of opening. Furthermore, crimping also allows the inner layers of each laminate to be combined into a single layer in which the third synthetic resin is integrated. This prevents problems such as peeling between the laminates and allows the tear tabs to function properly. For example, during extrusion blow molding, after the outer layer, biomass-blended resin layer, and inner layer are injected to form a parison, a part of the parison can be sandwiched in a molding die (not shown) to crimp the inner layers of the laminate together in an overlapping state. This makes it possible to form a pair of tear-off tabs. [Effects of the Invention]

[0023] The extrusion blown container according to the present invention can reduce the environmental impact and prevent the biomass-blended resin layer from changing in quality or deteriorating. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is a front view (partial cross-sectional view) showing an embodiment of an extrusion blow container according to the present invention. [Figure 2] FIG. 2 is a side view of the extrusion blow container shown in FIG. [Figure 3] FIG. 2 is a top view of the extrusion blown container shown in FIG. [Figure 4] FIG. 2 is an enlarged cross-sectional view of a portion A shown in FIG. [Figure 5] FIG. 2 is an enlarged front view of the tearer unit shown in FIG. [Figure 6] 6 is a side view of the tearing pieces that make up the tearing unit shown in FIG. 5, as seen from the direction of arrow B. FIG. [Figure 7]6 is a cross-sectional view of the tearing piece taken along line CC shown in FIG. 5. DETAILED DESCRIPTION OF THE INVENTION

[0025] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an extrusion blown container according to the present invention will be described below with reference to the drawings. As shown in Figures 1 to 3, the extrusion blow container 1 of this embodiment is an EBM container made of synthetic resin, and includes a bottomed, cylindrical container body 2 for containing contents (not shown), and a tear-off part 3 for closing the mouth 10 of the container body 2.

[0026] Examples of contents include food such as beverages and seasonings, cosmetics such as emulsions, beauty serums, and creams to be applied to the skin, detergents, medicines, etc. However, this is not limited to this case, and the contents are not limited to any particular item.

[0027] The extrusion blow molding process for the extrusion blow container 1 involves injecting heated and melted material to form a parison, and then blowing air into the parison in a mold (not shown). Therefore, the container body 2 and the gripping part 3 are molded integrally with each other.

[0028] The container body 2 and tear-off part 3 are arranged coaxially with a common axis, the container axis O. In this embodiment, the tear-off part 3 side along the container axis O is defined as the upper side, and the container body 2 side is defined as the lower side. Furthermore, in a plan view seen from the direction of the container axis O, the direction intersecting the container axis O is defined as the radial direction, and the direction circumferential around the container axis O is defined as the circumferential direction. Furthermore, one of the radial directions that are perpendicular to each other is defined as the front-rear direction L1, and the other direction is defined as the left-right direction L2. Furthermore, among the circumferential directions, the direction that rotates clockwise around the container axis O in a top view of the extrusion-blow container 1 is defined as a first rotation direction M1, and the direction that rotates counterclockwise around the container axis O is defined as a second rotation direction M2.

[0029] (Container body) The container body 2 is formed in a bottomed cylindrical shape with a mouth 10, a shoulder 11, a body 12, and a bottom 13 arranged in this order from above. The mouth 10 of the container body 2 is formed to extend upward from the inner peripheral edge of the shoulder 11. A male thread 14 is formed around the entire periphery of the outer peripheral surface of the mouth 10, onto which a cap (not shown) is screwed after the tear piece 3 is removed from the container body 2 to open it.

[0030] However, the method of attaching the cap is not limited to screwing, and it may be attached to the mouth portion 10 by, for example, undercut fitting. In this case, a fitting protrusion for undercut fitting of the cap may be formed on the outer peripheral surface of the mouth portion 10 instead of the male thread portion 14. When attaching the cap to the mouth portion 10 by undercut fitting, the cap may also be a hinged cap, for example.

[0031] The shoulder portion 11 is continuous with the lower end of the mouth portion 10, and expands in diameter so as to extend radially outward as it extends downward from the lower end of the mouth portion 10. In the illustrated example, the shoulder portion 11 is formed in an elliptical shape that is longer in the left-right direction L2 than in the front-rear direction L1 in a plan view seen from above.

[0032] The body portion 12 is continuous with the outer peripheral edge of the shoulder portion 11 and is formed to extend downward from the outer peripheral edge of the shoulder portion 11. As shown in Fig. 1, the body portion 12 is formed to extend radially inward as it extends downward from the outer peripheral edge of the shoulder portion 11 in a front view seen in the front-rear direction L1. Therefore, the body portion 12 is formed to have an elliptical shape in a plan view seen from above, corresponding to the shape of the shoulder portion 11, and is formed to gradually narrow downward.

[0033] 1, the bottom 13 is formed by heat welding the lower opening of the body 12 in a crushed state so as to be flattened in the front-to-rear direction L1 after extrusion blow molding. As a result, the container body 2 is formed into a tube shape in which the lower opening of the body 12 is closed (sealed) by the bottom 13. In this case, the bottom 13 is formed after the contents have been filled into the container body 2. Before the bottom 13 is formed, i.e., after the extrusion blow molding, the lower end of the body 12 is formed, for example, in a circular cross section and opens downward.

[0034] The container body 2 configured as described above has a laminated structure in which multiple layers are stacked. Specifically, as shown in Figures 1 and 4, it has a laminated (three-layer) structure including an outer layer 20, a paper-blended resin layer 21 (a biomass-blended resin layer according to the present invention), and an inner layer 22, which are stacked in this order from the outside in the radial direction.

[0035] The outer layer 20 is formed from a first synthetic resin and constitutes the outer surface of the container body 2. The first synthetic resin is not particularly limited, but examples thereof include synthetic resins whose main component is polyethylene terephthalate resin (PET resin). Note that the main component PET resin may further contain other synthetic resins such as polyethylene resin (PE resin), polypropylene resin (PP resin), low-density polyethylene resin (LDPE resin), linear low-density polyethylene resin (LLDPE resin), etc. In particular, from the viewpoint of environmental compatibility, it is preferable that the resin contains a plant-derived resin.

[0036] The paper-blended resin layer 21 functions as an intermediate layer disposed between the outer layer 20 and the inner layer 22. The paper-blended resin layer 21 contains a paper component 21a (see FIG. 4) as a biomass material and is formed from a paper-blended resin (biomass-blended resin according to the present invention) containing a second synthetic resin, and is disposed radially inward of the outer layer 20.

[0037] The second synthetic resin is not particularly limited, but may be, for example, a polyolefin resin. An example of a paper compound resin containing this type of polyolefin resin and the paper component 21a is MAPKA (registered trademark) manufactured by Environmental Management Research Institute Co., Ltd. Because paper-blended resins have the problem of absorbing moisture, they are preferably dried, for example, at 80°C for at least 6 hours before molding. Specifically, the paper-blended resin is preferably in a dry state with a moisture content of about 500 ppm or less at the start of molding.

[0038] Furthermore, the paper-blended resin layer 21 may be formed of a blend resin of a paper-blended resin containing a paper component 21a and a PP resin, and an olefin-based resin such as an LDPE resin. The paper-blended resin layer 21 may contain additives for the purpose of improving compatibility or other modifications.

[0039] Furthermore, the MFR (melt mass flow rate) of the paper-blended resin layer 21 is preferably, for example, 5 g / 10 min (230°C, 2.16 kg) or less, and more preferably 0.6 to 1.3 g / 10 min (230°C, 2.16 kg). The MFR is one of the scales for measuring the fluidity of a paper-blended resin when it is heated and melted. Furthermore, in the paper-blended resin layer 21, the proportion of the paper component 21a contained in the paper-blended resin is preferably 30% by weight or less.

[0040] The inner layer 22 is formed from a third synthetic resin and constitutes the inner surface of the container body 2. Therefore, the inner layer 22 is disposed radially inward of the paper-blended resin layer 21. The third synthetic resin is not particularly limited, but may be the same material as the first synthetic resin, for example. The first synthetic resin and the third synthetic resin may be the same material or different materials.

[0041] Furthermore, in this embodiment, for example, when forming the bottom 13, before heat welding, the lower end of the outer layer 20 constituting the body 12 is bent radially inward approximately horizontally, or the lower end of the inner layer 22 constituting the body 12 is bent radially outward approximately horizontally. This makes it possible to protect the lower end of the paper-blended resin layer 21 by using the outer layer 20 or the inner layer 22 to cover it from below, and in this state, the outer layer 20 and the inner layer 22 are heat-welded to each other. This makes it possible to cover the lower end of the paper-blended resin layer 21 over the entire periphery, preventing the paper-blended resin layer 21 from being exposed to the outside.

[0042] After the above pre-processing, the lower end opening of the body 12 is crushed so as to be flat in the front-to-rear direction L1, and the inner layers 22 are heat-sealed together in this state, thereby forming the bottom 13 and completing the tubular container body 2.

[0043] (Ticker section) As shown in Figures 1 to 3 and 5 to 7, the tear-off portion 3 is positioned above the mouth 10 of the container body 2 and is integrally molded with the mouth 10 of the container body 2 by extrusion blow molding via a breakable main weakened portion (weakened portion according to the present invention) 30. The tearing unit 3 includes a cylindrical tearing cap 40 with a top that is arranged coaxially with the container axis O, and a pair of tearing pieces 50 that are integrally formed with the tearing cap 40.

[0044] The tear-off cap 40 is connected to the entire periphery of the upper opening edge of the mouth 10 of the container body 2 via the main weakened portion 30, and closes the mouth 10 of the container body 2 from above. The tear-off cap 40 is formed in a topped cylindrical shape with a cap tube 41 formed with the same diameter as the mouth 10 of the container body 2, and a cap top wall 42 extending upward from the upper end of the cap tube 41. The main weakened portion 30 is a thin-walled portion formed over the entire periphery between the lower end of the cap tube 41 and the upper opening edge of the mouth portion 10 of the container body 2.

[0045] 2, the cap top wall 42 is formed so as to narrow in the front-rear direction L1 as it extends upward from the upper end of the cap tube 41. However, the shape of the cap top wall 42 is not limited to this, and it may be formed so as to narrow overall in diameter as it extends upward from the upper end of the cap tube 41.

[0046] The pair of tear pieces 50 are arranged side by side in the left-right direction L2 with the tear cap 40 sandwiched between them when viewed from the front in the front-rear direction L1. The pair of tear pieces 50 are formed integrally with the tear cap 40 so as to protrude radially outward from the tear cap 40. In the illustrated example, the pair of tear pieces 50 are formed in the shape of a plate that is thin in the front-rear direction L1 and has a constant length in the left-right direction L2 and up-down directions when viewed from the front. Therefore, as shown in FIG. 1, the tearing portion 3 has an overall T-shape when viewed from the front in the front-rear direction L1.

[0047] As shown in Figures 1 to 3 and 5 to 7, the pair of tear-off pieces 50 have inner ends 51 that are integrally formed with the outer peripheral surface of the cap tube 41, and are formed so as to extend downward from the outer peripheral surface of the cap tube 41 toward the radially outward direction along the left-right direction L2. Therefore, the pair of tear pieces 50 are formed so as to slope diagonally downward as they extend outward in the left-right direction L2, so that the lower ends of the pair of tear pieces 50 are positioned outward in the left-right direction L2 relative to the upper end of the opening 10 of the container body 2, which is located above the male thread portion 14.

[0048] The outer peripheral surface of the upper end of the mouth 10 of the container body 2 and the inner peripheral surface of the lower end of the pair of tear pieces 50 are integrally molded via a breakable auxiliary weakened portion 31. The auxiliary weakened portion 31 is thin-walled like the main weakened portion 30. The auxiliary weakened portion 31 is not essential and may not be provided.

[0049] The inner ends (root portions) 51 of the pair of tear pieces 50 are thicker than the outer ends (free ends) 52 of the tear pieces 50. Therefore, the pair of tear pieces 50 are connected to the cap tube 41 via the inner ends 51, which have appropriate rigidity. This makes it difficult for the pair of tear pieces 50 to undergo unintended deformation, such as bending or flexing in the circumferential direction, with the inner ends 51 as the base point.

[0050] Furthermore, in this embodiment, a horizontal rib 45 is formed above the cap top wall 42 and extends in the left-right direction L2. The horizontal rib 45 is molded integrally with the cap top wall 42 and with the inner ends 51 of the pair of tear pieces 50. Therefore, the horizontal rib 45 traverses the tear cap 40 in the left-right direction L2, connecting the pair of tear pieces 50 to each other in the left-right direction L2. This allows the tear cap 40 and the pair of tear pieces 50 to be molded more firmly together via the horizontal rib 45.

[0051] Furthermore, each of the pair of tearing pieces 50 has a finger-hook recess 53 recessed in the circumferential direction. Specifically, each of the pair of tearing pieces 50 has a bulging portion 54 that bulges in the first rotation direction M1. The internal space of this bulging portion 54 functions as the finger-hook recess 53 and is open in the second rotation direction M2.

[0052] In the tear portion 3 configured as described above, the main weakened portion 30 and the auxiliary weakened portion 31 are made easily breakable as the tear portion 3 rotates relative to the mouth portion 10 of the container body 2 around the container axis O.

[0053] Furthermore, at least one pair of tear pieces 50 in the tear section 3 configured as described above has a multilayer structure in which two laminates 23 are stacked together, each laminate having an outer layer 20, a paper-blended resin layer 21, and an inner layer 22. Specifically, each pair of tear pieces 50 has a multilayer structure in which the laminates 23 are pressed together with their inner layers 22 overlapping each other. This allows the tear tab 50 to have a predetermined thickness and ensure rigidity, improving the ease of opening. Furthermore, the inner layers 22 of each laminate 23 are bonded together to form a single layer of the third synthetic resin. This gives the pair of tear tabs 50 a multilayer (five-layer) structure in which, along the front-to-rear direction L1, the outer layer 20, the paper-blended resin layer 21, a layer in which the inner layers 22 are integrated, the paper-blended resin layer 21, and the outer layer 20 are stacked. In particular, because the inner layers 22 of each laminate 23 are bonded together, problems such as peeling between the laminates 23 can be prevented, allowing the tear tab 50 to function properly.

[0054] For example, during extrusion blow molding, after the outer layer 20, the paper-blended resin layer 21, and the inner layer 22 are injected to form a parison, a part of the parison can be sandwiched in a molding die (not shown) to crimp the inner layers 22 of the laminate 23 together in a stacked state. This makes it possible to form a pair of tear pieces 50. In particular, by clamping the pair of tear pieces 50 in the molding die, it is possible to form the outer shape of the pair of tear pieces 50, the thickness of the tear piece 50 including the inner end 51 and the outer end 52, the finger hook recess 53 and bulge 54, the horizontal rib 45, etc. as designed.

[0055] (Effect of extrusion blown container) Next, according to the extrusion-blow container 1 configured as described above, the entire container body 2 including the mouth portion 10 can have a three-layer laminate structure of the outer layer 20, the paper-blended resin layer 21, and the inner layer 22. In particular, the paper-blended resin layer 21, which is an intermediate layer disposed between the outer layer 20 and the inner layer 22, is formed from a paper-blended resin containing a paper component 21a. Therefore, by using the paper component 21a, the amount of synthetic resin used can be reduced, and for example, CO2 emissions can be reduced. This can contribute to reducing the environmental load.

[0056] Furthermore, because the mouth 10 of the container body 2 and the tear tab 3 are integrally molded by extrusion blow molding, there is no need to perform conventional finishing processes such as heat cutting on the upper opening edge of the mouth 10 of the container body 2 after molding, or heat sealing a sealing material. This prevents the paper component 21a from burning due to the effects of heat. This prevents the paper-blended resin layer 21 from changing or deteriorating, resulting in an extrusion blown container 1 with the quality and rigidity of the container body 2 properly maintained.

[0057] When using the container in an unused state, external force can be applied to the tearing part 3 with a fingertip or the like to break the main weakened part 30 and the auxiliary weakened part 31, for example by tearing, and the tearing part 3 can be removed by tearing it off from the mouth 10 of the container body 2. This allows the mouth 10 of the container body 2 to be opened, making it possible to use the contents.

[0058] Therefore, according to the extrusion blown container 1 of this embodiment, it is possible to reduce the environmental load and prevent the paper-blended resin layer 21 from changing in quality and deteriorating.

[0059] Furthermore, when opening the mouth 10 of the container body 2, the entire tear portion 3 can be rotated using the pair of tear pieces 50 with the fingertips or the like, which allows stress to be applied evenly and efficiently to the main weakened portion 30 and the auxiliary weakened portion 31. As a result, after the auxiliary weakened portion 31 is broken, the main weakened portion 30 can be smoothly broken around the entire circumference of the mouth 10 of the container body 2, and the tear cap 40 can be removed from the mouth 10 of the container body 2.

[0060] In particular, since the entire tear-off portion 3 can be removed while rotating it around the container axis O, when removing the tear-off portion 3, the stress transmitted from the tear-off portion 3 to the mouth portion 10 can be prevented from acting in a concentrated manner on, for example, the shoulder portion 11 or a part of the body portion 12 of the container body 2. If stress were to concentrate on a part of the shoulder 11 or body 12 of the container body 2, it could potentially cause bending or denting of the container body 2. In particular, since the middle layer constituting the container body 2 is the paper-blended resin layer 21 containing the paper component 21a, if stress were to concentrate locally, it would be even more likely to cause bending or denting of the container body 2 due to its rigidity. Therefore, by removing the gripping part 3 while rotating the container around the axis O of the container, the opening 10 of the container body 2 can be opened without causing bending or denting of the container body 2.

[0061] Furthermore, each of the pair of tear pieces 50 has a finger recess 53 that opens in the same direction (second rotation direction M2), so that the tear part 3 can be rotated around the container axis O in the first rotation direction M1 while hooking a fingertip into the finger recess 53. This allows for efficient application of stress to the tear part 3, improving the operability of opening the container.

[0062] Furthermore, by keeping the proportion of the paper component 21a contained in the paper-blended resin at 30% by weight or less, it is possible to prevent the paper component 21a from being contained in an excessively large amount while reducing the amount of synthetic resin used. Therefore, when the heated and melted paper-blended resin is injected to form, for example, a parison during extrusion blow molding, it is possible to prevent the paper component 21a from burning and causing deterioration or alteration of the paper-blended resin layer 21.

[0063] Furthermore, when the paper-blended resin layer 21 is formed from a blend of a paper-blended resin and an olefin-based resin, the inclusion of the flexible olefin-based resin can suppress uneven circumferential stretching. Therefore, the container body 2 can be easily molded into a desired shape. Furthermore, since the olefin-based resin has the property of being easily molded at low temperatures, the paper component 21a is even less likely to burn during extrusion blow molding.

[0064] Although the embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. The present embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. Furthermore, the present embodiments and their modifications include, for example, those that can be easily imagined by a person skilled in the art, those that are substantially the same, and those that are equivalent.

[0065] For example, the shape of the container body 2 is not limited to the above-described shape and may be changed as appropriate depending on, for example, the size, capacity, type of contents, and application of the container body 2. For example, the container body 2 may be an EBM bottle in which the body 12 is formed in a straight cylindrical shape along its entire length, or a rectangular bottle (EBM bottle) in which the body 12 is formed in a polygonal shape in cross section. In this case, the bottom 13 may be formed integrally. Furthermore, the container body 2 may not have a shoulder portion 11, but may have a reduced diameter at the upper end of the body portion 12, and the reduced diameter upper end of the body portion 12 may be connected to the lower end of the mouth portion 10.

[0066] Furthermore, the shape of the tear portion 3 is not limited to the above-mentioned case, and the shape may be changed as appropriate as long as it can be removed from the mouth portion 10 of the container body 2 by breaking the weakened portion. However, it is preferable to configure the tearing part 3 so that it can be removed by rotating it around the container axis O. Furthermore, in the above embodiment, as shown in Fig. 1, the length N1 of the entire tearing part 3 along the left-right direction L2 is formed to be smaller than the maximum diameter N2 of the body 12 of the container body 2 along the left-right direction L2. In this way, it is preferable to form the diameter (width) of the tearing part 3 to be smaller than or equal to the maximum diameter of the body 12 of the container body 2.

[0067] Furthermore, in the above embodiment, the paper component 21a is used as the biomass material, and the paper-blended resin layer 21 having a paper-blended resin is used as an example, but the biomass material is not limited to the paper component 21a. For example, various plant-derived materials such as rice flour, wood flour, and eggshell powder can be used as the biomass material, and the biomass-blended resin layer may contain these biomass materials. Note that when the paper component 21a is used as the main component as in this embodiment, the biomass material can be made inexpensive, which makes it easy to reduce the manufacturing cost of the extrusion-blow container 1.

[0068] Furthermore, the present invention includes the following aspects. <1> a cylindrical container body with a bottom that accommodates contents; a tearing part that is integrally formed with the mouth of the container body via a breakable weakened part and closes the mouth of the container body, The entire container body is an outer layer formed of a first synthetic resin; A biomass-blended resin layer formed of a biomass-blended resin containing a biomass material and a second synthetic resin and disposed radially inward of the container body relative to the outer layer; An extrusion blown container characterized by having a laminated structure including an inner layer formed from a third synthetic resin and arranged radially inward of the container body relative to the biomass-blended resin layer. <2> <1> In the extrusion blown container described in The biomass material is an extrusion-blown container containing a paper component as a main component. <3> <1> or <2> In the extrusion blown container described in An extrusion-blow container, wherein the biomass material contained in the biomass-blended resin is 30% by weight or less. <4> <1> from <3> In the extrusion blown container according to any one of the above items, The biomass-blended resin layer is formed from a blend resin of the biomass-blended resin and an olefin-based resin. <5> <1> from <4> In the extrusion blown container according to any one of the above items, The tearing unit is a topped, cylindrical tear-off cap that is arranged coaxially with the container axis and is connected to the upper opening edge of the mouth of the container body along the entire circumference via the weakened portion, and closes the mouth of the container body from above; a pair of tear pieces protruding radially outward from the tear cap and disposed on either side of the container axis; The extrusion blow container, wherein the weakened portion is easily broken as the tear-off cap rotates around the container axis. <6> <5> In the extrusion blown container described in The pair of tear pieces each have a finger-hook recess formed thereon, recessed in a circumferential direction around the axis of the container. <7> <5> or <6> In the extrusion blown container described in At least one pair of the tear pieces of the extrusion blown container has a multilayer structure in which a laminate consisting of the outer layer, the biomass-blended resin layer, and the inner layer is laminated and pressed together with the inner layers overlapping each other. [Explanation of symbols]

[0069] O…Container axis 1...Extrusion blown container 2...Container body 3... Picking section 10...mouth of container body 20…outer layer 21...Paper-blended resin layer (biomass-blended resin layer) 21a...Paper components (biomass materials) 22...Inner layer 23...Laminate 30...Main weakened section (weakened section) 40...Tear cap 50...Tear pieces 53...finger hook recess

Claims

1. a cylindrical container body with a bottom that accommodates contents; a tearing part that is integrally formed with the mouth of the container body via a breakable weakened part and closes the mouth of the container body, The entire container body is an outer layer formed of a first synthetic resin; a biomass-blended resin layer formed of a biomass-blended resin containing a biomass material and a second synthetic resin and disposed radially inward of the container body relative to the outer layer; An extrusion blown container characterized by having a laminated structure including an inner layer formed from a third synthetic resin and arranged radially inward of the container body relative to the biomass-blended resin layer.

2. 2. The extrusion blown container according to claim 1, The biomass material is an extrusion-blown container containing a paper component as a main component.

3. 2. The extrusion blown container according to claim 1, An extrusion-blown container, wherein the biomass material contained in the biomass-blended resin is 30% by weight or less.

4. The extrusion blown container according to claim 1 or 2, The biomass-blended resin layer is formed from a blend resin of the biomass-blended resin and an olefin-based resin.

5. 2. The extrusion blown container according to claim 1, The tearing unit is a topped, cylindrical tear-off cap that is arranged coaxially with the container axis and is connected to the upper opening edge of the mouth of the container body along the entire circumference via the weakened portion, and closes the mouth of the container body from above; a pair of tear pieces protruding radially outward from the tear cap and disposed on either side of the container axis; The extrusion blow container, wherein the weakened portion is easily broken as the tear-off cap rotates around the container axis.

6. 6. The extrusion blown container according to claim 5, The pair of tear pieces each have a finger-hook recess formed thereon, recessed in a circumferential direction around the axis of the container.

7. 7. The extrusion blown container according to claim 5 or 6, At least one pair of the tear pieces of the extrusion blown container has a multilayer structure in which a laminate consisting of the outer layer, the biomass-blended resin layer, and the inner layer is laminated and pressed together with the inner layers overlapping each other.

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