Plastic bottle

Abstract

To provide a plastic bottle in which deformation of a bottom portion can be suppressed.SOLUTION: A plastic bottle 10 includes a mouth portion 20, a body portion 50, and a bottom portion 80. The body portion 50 includes an upper rectangular-tubular portion 60 located on the side of the mouth portion 20, a lower rectangular-tubular portion 70 located on the side of the bottom portion 80 relative to the upper rectangular-tubular portion 60, and a concave rib 51 located between the upper rectangular-tubular portion 60 and the lower rectangular-tubular portion 70. The bottom portion 80 includes a central portion 81 and a peripheral portion 82 located around the central portion 81. A protrusion 84 projecting radially inward and downward is formed in the central portion 81. The height H of the bottom portion 80 is from 8 mm to 30 mm inclusive.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to plastic bottles. [Background technology]

[0002] BACKGROUND ART Conventionally, plastic bottles have been produced by biaxially stretching and blow molding a polyethylene terephthalate preform produced by, for example, injection molding. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-13664 Summary of the Invention [Problem to be solved by the invention]

[0004] The produced plastic bottle is filled with contents through its mouth. In this case, the contents may be filled at a high temperature (for example, from about 70°C to 90°C) through the mouth. When filling a plastic bottle with high-temperature contents, it is necessary to suppress the expansion of the bottom.

[0005] The present disclosure has been made in consideration of these points, and aims to provide a plastic bottle that can suppress deformation of the bottom. [Means for solving the problem]

[0006] The embodiments of the present disclosure relate to the following [1] to [4].

[0007] [1] It has a mouth, a body, and a bottom, The body portion is an upper rectangular tube portion located on the mouth portion side; a lower rectangular tube portion located closer to the bottom than the upper rectangular tube portion; a concave rib located between the upper rectangular tube portion and the lower rectangular tube portion, the bottom portion has a central portion and a peripheral portion located around the central portion; A protrusion is formed in the central portion so as to protrude radially inward and downward, A plastic bottle, wherein the height of the bottom is 8 mm or more and 30 mm or less.

[0008] [2] an upper panel portion is formed on the upper rectangular tube portion, a lower panel portion is formed on the lower rectangular tube portion, The plastic bottle according to [1], wherein the width of the upper panel portion and the width of the lower panel portion gradually increase toward the concave rib side.

[0009] [3] A plurality of upper convex ribs are formed on the upper panel portion, The plastic bottle according to [2], wherein a plurality of lower convex ribs are formed on the lower panel portion.

[0010] [4] The plastic bottle according to [3], wherein the length of each of the upper convex ribs and the length of each of the lower convex ribs gradually increase as they approach the concave rib. [Effects of the Invention]

[0011] According to the present disclosure, deformation of the bottom portion can be suppressed. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a front view showing a plastic bottle according to one embodiment. [Figure 2] FIG. 2 is a plan view showing a plastic bottle according to one embodiment. [Figure 3] FIG. 3 is a bottom view showing a plastic bottle according to one embodiment. [Figure 4]FIG. 4 is a vertical cross-sectional view (cross-sectional view taken along line IV-IV in FIG. 3) showing the bottom of a plastic bottle according to one embodiment. [Figure 5] FIG. 5 is a diagram illustrating the operation of the plastic bottle according to one embodiment. [Figure 6] FIG. 6 is a diagram illustrating the operation of the plastic bottle according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] An embodiment of the present disclosure will be described below with reference to the drawings. FIGS. 1 to 6 are diagrams illustrating an embodiment of the present disclosure. The following figures are schematic diagrams. Therefore, the size and shape of each part are appropriately exaggerated for ease of understanding. Furthermore, appropriate modifications can be made within the scope of the technical concept. In the following figures, identical parts are denoted by the same reference numerals, and some detailed descriptions may be omitted. Furthermore, the numerical values, such as dimensions, and material names of each component described in this specification are examples of an embodiment and are not limited thereto and may be appropriately selected and used. In this specification, terms specifying shapes or geometric conditions, such as parallel, orthogonal, and perpendicular, are interpreted not only strictly but also to include substantially the same state.

[0014] First, a plastic bottle 10 according to this embodiment will be described with reference to Figures 1 to 4. In this specification, "upper" and "lower" refer to the upper and lower sides, respectively, of the plastic bottle 10 when it is held upright (Figure 1). In this specification, the "central axis CL" of the plastic bottle 10 refers to the central axis of the cylinder that forms the inner surface of the mouth portion 20 of the plastic bottle 10. The central axis CL of the plastic bottle 10 is a straight line that is perpendicular to the plane that forms the contact surface when the plastic bottle 10 is placed on the ground in an upright position.

[0015] In this specification, the term "height direction" refers to the direction along the central axis CL of the plastic bottle 10, and the term "radial direction" refers to the direction perpendicular to the central axis CL of the plastic bottle 10. The term "circumferential direction" refers to the circumferential direction of a circle centered on the central axis CL of the plastic bottle 10.

[0016] The plastic bottle 10 shown in FIGS. 1 to 4 is produced by preparing a preform obtained by injection molding and then subjecting this preform to biaxial stretch blow molding.

[0017] As shown in FIG. 1, the plastic bottle 10 has a mouth 20, a neck 21 located below the mouth 20, a shoulder 30 located below the neck 21, a body 50 located below the shoulder 30, and a bottom 80 located below the body 50.

[0018] Of these, mouth portion 20 has a threaded portion 23 that is screwed onto a cap (not shown), and a flange portion 24 located below threaded portion 23. The plastic bottle 10 is filled with contents such as liquid, and a cap is screwed onto mouth portion 20 to obtain a container containing the contents.

[0019] The neck portion 21 is located between the flange portion 24 and the shoulder portion 30, and has a generally cylindrical shape with a generally uniform diameter.

[0020] The shoulder portion 30 is located between the neck portion 21 and the body portion 50, and has a shape in which the diameter gradually increases from the neck portion 21 side toward the body portion 50 side. The shoulder portion 30 has a substantially octagonal shape in a cross section parallel to the horizontal plane S on which the plastic bottle 10 is placed (hereinafter also referred to as a horizontal cross section).

[0021] The shoulder portion 30 has a first shoulder portion 31 connected to the neck portion 21 and a second shoulder portion 32 located below the first shoulder portion 31. In a front view, the inclination angle θ1 of the first shoulder portion 31 relative to the central axis CL of the plastic bottle 10 is larger than the inclination angle θ2 of the second shoulder portion 32 relative to the central axis CL.

[0022] Of the boundary lines VL between the first shoulder portion 31 and the second shoulder portion 32, the boundary line VL located on the boundary surface 62 of the upper rectangular tube portion 60 described below is formed in a V shape, thereby improving the vertical load strength.

[0023] The second shoulder portion 32 is formed with grooves 33 recessed toward the inside of the plastic bottle 10. By forming the grooves 33 in the second shoulder portion 32 in this way, the rigidity of the shoulder portion 30 can be increased. As shown in FIG. 2, in this embodiment, four grooves 33 are formed. The four grooves 33 are arranged at equal intervals along the circumferential direction. Specifically, each groove 33 is formed on a side surface 61 of the upper rectangular tube portion 60, which will be described later. However, the number of grooves 33 is not limited to this.

[0024] 1, the groove 33 extends horizontally. The length (horizontal distance) of the groove 33 gradually increases toward the first shoulder 31 (upper side). This improves the vertical load strength.

[0025] The body 50 has an upper square tube portion 60 located on the mouth 20 side, a lower square tube portion 70 located closer to the bottom 80 than the upper square tube portion 60, and a concave rib 51 located between the upper square tube portion 60 and the lower square tube portion 70.

[0026] Of these, the upper rectangular tube portion 60 includes four side surfaces 61 of the same shape and boundary surfaces 62 formed between adjacent side surfaces 61. This upper rectangular tube portion 60 has an octagonal tube shape as a whole.

[0027] The width (horizontal distance) of the side surface 61 gradually increases toward the recessed rib 51 (the lower side in FIG. 1), thereby improving the vertical load strength. As will be described later, an upper panel portion 63 and the like are formed on this side surface 61.

[0028] The boundary surface 62 is a flat surface. The width (horizontal distance) of the boundary surface 62 gradually narrows toward the concave rib 51 side (the lower side in FIG. 1).

[0029] An upper panel portion 63 is formed on the upper rectangular tube portion 60. This upper panel portion 63 is formed on the side surface 61 of the upper rectangular tube portion 60. The upper panel portion 63 is recessed toward the inside of the plastic bottle 10. This upper panel portion 63 absorbs the pressure applied to the plastic bottle 10 when the plastic bottle 10 expands or decompresses.

[0030] The width (horizontal distance) of the upper panel portion 63 gradually increases toward the recessed rib 51 side (the lower side in FIG. 1), thereby effectively suppressing deformation of the central portion of the body portion 50 when filling or cooling.

[0031] A plurality of upper convex ribs 64 are formed on the upper panel portion 63. Each of the upper convex ribs 64 protrudes outward from the plastic bottle 10. The upper convex ribs 64 serve to increase the strength of the upper rectangular tube portion 60. In this embodiment, three upper convex ribs 64 are formed. The number of upper convex ribs 64 may be two or less, or may be four or more.

[0032] The length (horizontal distance) of each upper convex rib 64 gradually increases as it approaches the concave rib 51. This causes the strength of the upper rectangular tube portion 60 to gradually increase toward the concave rib 51. This effectively prevents deformation of the central portion of the body portion 50 when filling or cooling.

[0033] A first upper groove 65 is formed above the upper panel portion 63. A second upper groove 66 is formed below the upper panel portion 63. The first upper groove 65 and the second upper groove 66 each extend horizontally. The first upper groove 65 and the second upper groove 66 each recess toward the inside of the plastic bottle 10. The first upper groove 65 and the second upper groove 66 serve to increase the strength of the upper rectangular tube portion 60.

[0034] In this embodiment, the length (horizontal distance) of the first upper groove 65 is shorter than the length (horizontal distance) of the second upper groove 66. In other words, the length of the second upper groove 66, which is located closer to the concave rib 51 (lower side in FIG. 1 ) than the first upper groove 65, is longer than the length of the first upper groove 65. This effectively increases the strength of the lower part of the upper rectangular tube portion 60. Therefore, deformation of the central portion of the body portion 50 during filling or cooling can be effectively suppressed.

[0035] The lower rectangular tube portion 70 has four side surfaces 71 of the same shape and boundary surfaces 72 formed between adjacent side surfaces 71. The lower rectangular tube portion 70 has an octagonal tube shape as a whole.

[0036] The width (horizontal distance) of the side surface 71 gradually increases toward the recessed rib 51 side (upper side in FIG. 1). This improves the shaping property during blow molding. As will be described later, a lower panel portion 73 and the like are formed on this side surface 71.

[0037] The boundary surface 72 is a flat surface. The width (horizontal distance) of the boundary surface 72 gradually narrows toward the concave rib 51 side (upper side in FIG. 1).

[0038] A lower panel portion 73 is formed on the lower rectangular tube portion 70. This lower panel portion 73 is formed on the side surface 71 of the lower rectangular tube portion 70. The lower panel portion 73 is recessed toward the inside of the plastic bottle 10. This lower panel portion 73 absorbs the pressure applied to the plastic bottle 10 when the plastic bottle 10 expands or decompresses.

[0039] The width (horizontal distance) of the lower panel portion 73 gradually increases toward the recessed rib 51 side (upper side in Figure 1), thereby effectively suppressing deformation of the central portion of the body portion 50 when filling or cooling.

[0040] A plurality of lower convex ribs 74 are formed on the lower panel portion 73. Each lower convex rib 74 protrudes outward from the plastic bottle 10. The lower convex ribs 74 serve to increase the strength of the lower rectangular tube portion 70. In this embodiment, four lower convex ribs 74 are formed. The number of lower convex ribs 74 may be three or less, or five or more.

[0041] The length (horizontal distance) of each lower convex rib 74 gradually increases as it approaches the concave rib 51. This causes the strength of the lower rectangular tube portion 70 to gradually increase toward the concave rib 51. This effectively prevents deformation of the central portion of the body portion 50 when filling or cooling.

[0042] A first lower groove 75 is formed above the lower panel portion 73. A second lower groove 76 is formed below the lower panel portion 73. The first lower groove 75 and the second lower groove 76 each extend horizontally. The first lower groove 75 and the second lower groove 76 each recess toward the inside of the plastic bottle 10. The first lower groove 75 and the second lower groove 76 serve to increase the strength of the lower rectangular tube portion 70.

[0043] In this embodiment, the length (horizontal distance) of the first lower groove 75 is longer than the length (horizontal distance) of the second lower groove 76. That is, the length of the first lower groove 75 located closer to the recessed rib 51 (upper side in FIG. 1 ) than the second lower groove 76 is longer than the length of the second lower groove 76. This effectively increases the strength of the upper part of the lower rectangular tube portion 70. Therefore, deformation of the central part of the body portion 50 during filling or cooling can be effectively suppressed.

[0044] As described above, the concave rib 51 of the body 50 is located between the upper rectangular tube portion 60 and the lower rectangular tube portion 70. The concave rib 51 includes an inter-side surface rib 52 located between the side surfaces 61 and 71, and an inter-boundary surface rib 53 located between the boundary surfaces 62 and 72. The inter-side surface rib 52 includes a center portion 54 and a pair of end portions 55 provided on both sides of the center portion 54 in the horizontal direction. The height (vertical distance) of the center portion 54 is lower than the height (vertical distance) of the end portions 55. Furthermore, the height of the end portions 55 gradually increases with increasing distance from the center portion 54. Furthermore, the height of the inter-boundary surface rib 53 is higher than the height of the end portions 55.

[0045] Next, the bottom portion 80 will be described.

[0046] As shown in Figures 3 and 4, the bottom 80 has a central portion 81 that is recessed upward (toward the inside of the plastic bottle 10) and a peripheral portion 82 that is located around the central portion 81. Of these, the central portion 81 is located higher than the peripheral portion 82. A first protrusion 83 that protrudes downward is formed in the center of the central portion 81. This first protrusion 83 is a portion that results from a gate mark that occurs when the preform for producing the plastic bottle 10 is injection molded. The height (vertical distance) of this first protrusion 83 may be approximately 1 mm.

[0047] Second protrusions (protrusions) 84 that protrude radially inward and downward are formed in the central portion 81. In the illustrated example, eight second protrusions 84 are formed. Recesses 85 are formed between each of the second protrusions 84.

[0048] The second protrusion 84 includes a first inclined surface 84a and a second inclined surface 84b that is connected to the first inclined surface 84a and inclined relative to the first inclined surface 84a. The first inclined surface 84a is located radially outward and below the second inclined surface 84b. The first inclined surface 84a and the second inclined surface 84b each extend linearly in a vertical cross section of the bottom portion 80 (a cross section passing through the central axis CL).

[0049] The inclination angle θ3 (see FIG. 4) of the first inclined surface 84a relative to the central axis CL of the plastic bottle 10 may be greater than the inclination angle θ4 (see FIG. 4) of the second inclined surface 84b relative to the central axis CL. In this case, the inclination angle θ3 of the first inclined surface 84a relative to the central axis CL may be 40° or greater and 85° or less. The inclination angle θ4 of the second inclined surface 84b relative to the central axis CL may be 10° or greater and 40° or less. When the inclination angle θ3 is 40° or greater and the inclination angle θ4 is 10° or greater, the plastic bottle 10 can be easily released from a blow molding mold (not shown) after blow molding. Furthermore, when the inclination angle θ3 is 85° or less and the inclination angle θ4 is 40° or less, deformation of the central portion 81 can be effectively prevented when the pressure inside the plastic bottle 10 increases.

[0050] The height H1 of the first inclined surface 84a (see FIG. 4) may be lower than the height H2 of the second inclined surface 84b (see FIG. 4). This improves the formability during blow molding. In this case, the height H1 of the first inclined surface 84a may be 2 mm or more and 8 mm or less. The height H2 of the second inclined surface 84b may be 4 mm or more and 18 mm or less.

[0051] The height H of the bottom portion (see FIG. 4) is 8 mm or more and 30 mm or less. By making the height H of the bottom portion 80 8 mm or more, deformation (expansion) of the bottom portion 80 can be suppressed even when the plastic bottle 10 is filled with hot contents. Furthermore, by making the height H of the bottom portion 80 30 mm or less, overstretching during blow molding of the plastic bottle 10 can be suppressed. This prevents the plastic bottle 10 from becoming white.

[0052] However, the size of such plastic bottle 10 is not limited, and the bottle may be of any size. For example, the full capacity of plastic bottle 10 may be 200 ml to 2000 ml, preferably 300 ml to 1500 ml, and more preferably 450 ml to 1000 ml. For example, the full capacity of plastic bottle 10 may be 950 ml.

[0053] Furthermore, the weight of the plastic bottle 10 may be, but is not limited to, 10 g to 38 g, preferably 14 g to 28 g, when the full capacity is 2000 ml or less.

[0054] The plastic bottle 10 can also be produced by biaxially stretching and blow molding a preform made by injection molding a synthetic resin material. Thermoplastic resins can be used as the main material for the plastic bottle 10. Examples of thermoplastic resins that can be used include polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polylactic acid (PLA), and polycarbonate (PC). The plastic bottle 10 can also have a multilayer structure in which a barrier material layer is sandwiched between two polyethylene terephthalate layers. For example, a preform with a multilayer structure such as PET / MXD6 / PET can be produced and then biaxially stretched and blow molded to produce the plastic bottle 10, which is a multilayer container. The plastic bottle 10 can also be made from recycled plastic, which is produced by sorting, crushing, and cleaning used plastic products. The plastic bottle 10 can also be produced by various molding methods, such as biaxially stretching and blow molding, as well as direct blow molding.

[0055] Next, the operation of this embodiment having such a configuration will be described.

[0056] First, an empty plastic bottle 10 is prepared, and then the plastic bottle 10 is filled with contents such as a beverage. In this case, the contents may be filled at a high temperature (for example, between approximately 70°C and 90°C) through the mouth 20. In this case, as shown in FIG. 5, the heat of the contents may cause the body 50 and bottom 80 of the plastic bottle 10 to expand.

[0057] In contrast, in the present embodiment, the width of the upper panel portion 63 and the width of the lower panel portion 73 of the body portion 50 gradually increase toward the recessed rib 51 side, thereby suppressing deformation of the body portion 50. Also, in the present embodiment, a second protrusion 84 that protrudes radially inward and downward is formed in the central portion 81 of the bottom portion 80, and the height H of the bottom portion 80 is 8 mm or more. This suppresses deformation of the bottom portion 80.

[0058] Next, the opening 20 is closed with a cap (not shown).

[0059] The contents within the plastic bottle 10 are then cooled, for example, to room temperature. In this case, as shown in Figure 6, the cooling of the contents may cause the body 50 and bottom 80 of the plastic bottle 10 to shrink. Even in this case, in this embodiment, the widths of the upper panel portion 63 and the lower panel portion 73 of the body 50 gradually increase toward the recessed rib 51, thereby suppressing deformation of the body 50. Furthermore, a second protrusion 84 that protrudes radially inward and downward is formed in the central portion 81 of the bottom 80, and the height H of the bottom 80 is 8 mm or more, thereby suppressing deformation of the bottom 80.

[0060] As described above, according to this embodiment, the plastic bottle 10 includes a mouth 20, a body 50, and a bottom 80. The body 50 includes an upper rectangular tube portion 60 located closer to the mouth 20, a lower rectangular tube portion 70 located closer to the bottom 80 than the upper rectangular tube portion 60, and a recessed rib 51 located between the upper rectangular tube portion 60 and the lower rectangular tube portion 70. The bottom 80 includes a central portion 81 and a peripheral portion 82 located around the central portion 81. The central portion 81 is further formed with a second protrusion 84 that protrudes radially inward and downward. The height H of the bottom 80 is 8 mm or greater. This prevents deformation of the bottom 80 even when the plastic bottle 10 is filled with hot contents. Having a height H of the bottom 80 of 30 mm or less prevents excessive stretching during blow molding of the plastic bottle 10.

[0061] Furthermore, according to this embodiment, an upper panel portion 63 is formed in the upper rectangular tube portion 60, and a lower panel portion 73 is formed in the lower rectangular tube portion 70. The widths of the upper panel portion 63 and the lower panel portion 73 gradually increase toward the recessed rib 51. This effectively prevents deformation of the central portion of the body portion 50 when filling or cooling.

[0062] Furthermore, according to this embodiment, a plurality of upper convex ribs 64 are formed on the upper panel portion 63, and a plurality of lower convex ribs 74 are formed on the lower panel portion 73. This increases the strength of the upper rectangular tube portion 60 and the lower rectangular tube portion 70.

[0063] Furthermore, according to this embodiment, the length of each upper convex rib 64 and the length of each lower convex rib 74 gradually increase as they approach the concave rib 51. As a result, the strength of the upper rectangular tube portion 60 and the strength of the lower rectangular tube portion 70 gradually increase as they approach the concave rib 51. This effectively prevents deformation of the central portion of the body 50 when filling or cooling.

[0064] The components disclosed in the above embodiments and modifications may be combined as needed, or some components may be omitted from all the components disclosed in the above embodiments and modifications. [Explanation of symbols]

[0065] 10 plastic bottles 20 Mouth 50 Torso 51 concave rib 60 Upper square tube part 63 Upper panel 64 Upper convex rib 70 Lower rectangular tube 73 Lower panel 74 Lower convex rib 80 bottom 81 Central part 82 Periphery 84 Second protrusion

Claims

1. It has a mouth, a body, and a bottom, The body portion is an upper rectangular tube portion located on the mouth portion side; a lower rectangular tube portion located closer to the bottom than the upper rectangular tube portion; a concave rib located between the upper rectangular tube portion and the lower rectangular tube portion, the bottom portion has a central portion and a peripheral portion located around the central portion; A protrusion is formed in the central portion so as to protrude radially inward and downward, The height of the bottom is 8 mm or more and 30 mm or less, A plastic bottle having a full capacity of 200 ml to 2000 ml.

2. an upper panel portion is formed on the upper rectangular tube portion, a lower panel portion is formed on the lower rectangular tube portion, 2. The plastic bottle according to claim 1, wherein the width of the upper panel portion and the width of the lower panel portion gradually increase toward the concave rib side.

3. A plurality of upper convex ribs are formed on the upper panel portion, 3. The plastic bottle according to claim 2, wherein the lower panel portion is formed with a plurality of lower convex ribs.

4. 4. The plastic bottle according to claim 3, wherein the length of each of the upper convex ribs and the length of each of the lower convex ribs gradually increase as they approach the concave rib.

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