JP2018030643A - Plastic bottle and filling body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a square plastic bottle which combines lightweight properties with high strengh of a shoulder against an external force and which makes a label easy to be peeled, and a filling body.SOLUTION: A body 30 includes an upside prismatic part 50u that comprises a plurality of wall parts 31, and a corner part 32 for connecting the wall parts 31 adjoining each other in a circumferential direction. The upside prismatic part 50u is wrapped with a label. A PET bottle 1 has a ridge line 21 that is circumferentially extended between a shoulder 20 and the body 30. The ridge line 21 is positioned on the side nearest to the body 30 in the corner part 32. The shoulder 20 has a ridge line 24 that is protruded toward the outside of the PET bottle 1 and axially extended in such a manner that the circumferential center of the corner part 32 is set as a starting point.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a plastic bottle and a filling body, and more particularly to a weight-reduced plastic bottle and a filling body structure.

  As containers filled with beverages, plastic bottles, especially PET (PolyEthylene Terephthalate) bottles are often used. The market for large PET bottles is expanding due to demand for stockpiling and the impact of diversification of daily life. However, large PET bottles are difficult to hold because the weight increases due to the large volume of the filled bottle and the waistline becomes large.

  In Patent Document 1, a waist part having a reduced diameter is formed at a predetermined height position of the body part, and the waist part is periodically connected in the circumferential direction to form a wavy convex part. A synthetic resin round casing is disclosed in which a recess for a finger hook is formed.

Japanese Patent Laying-Open No. 2015-160656

  According to the synthetic resin round casing of Patent Document 1, even if the contents are fully filled and heavy with a large-capacity casing, the casing can be held more stably and the casing can be held in one hand. It is said that the content liquid can be poured out from the mouth tube part more easily by tilting the housing in the lifted state. Furthermore, according to the synthetic resin round casing of Patent Document 1, a plurality of wavy convex portions provided periodically serve as a support for supporting the casing, and the rigidity and buckling strength of the casing are high. It can be held at a level.

  In the synthetic resin round housing of Patent Document 1, the fingertip of the first finger is hung on the concave portion of the waist portion on the front side of the housing, the second finger or the third finger is hung on the concave portion of the waist portion on the back side, The third finger, the fourth finger, and the fifth finger, or the second finger, the fourth finger, and the fifth finger, which are other fingers, abut the body part and reach the fingertip of the other finger from the fingertip of the first finger It is said that the whole body can be firmly held. However, in this configuration, the fingers that protrude from the waist part grip the boundary between the waist part and the torso part with a larger trunk diameter, and the shape of the housing and the fingers do not fit perfectly. It is difficult to grip the housing. On the other hand, in the structure in which the length of the waist portion is extended in the height direction, this portion becomes a bending point, and the buckling strength of the synthetic resin round casing is reduced.

  Furthermore, in recent years, efforts have been made to reduce the weight of PET bottles by reducing the amount of raw materials used in order to save resources and reduce the environmental burden during transportation. And PET bottles tend to be thinner and lighter in strength as the weight is reduced. Accordingly, the lighter the PET bottle, the more severe the conditions for maintaining its strength. However, Patent Document 1 has no description about weight reduction of the PET bottle 1.

  By the way, the PET bottle includes a cylindrical round PET bottle and a square tubular square PET bottle. Compared to round PET bottles, square PET bottles have the same width and can increase the internal volume, have excellent loading efficiency during distribution and storage, display efficiency, and storage efficiency, and can be attached to containers There are advantages such as easy-to-read labels. On the other hand, a square PET bottle tends to be harder to hold than a round PET bottle due to the difference in distance between the diagonal direction and the facing direction and the difference in hardness at each position. However, the difference in shape may affect the willingness to purchase, and improving the ease of holding a square PET bottle is not as simple as changing the shape to a round PET bottle. The configuration described in Patent Document 1 is a round housing, and Patent Document 1 does not describe or suggest any square bottles having various advantages.

  Accordingly, an object of the present invention is to provide a rectangular plastic bottle and a filling body that have both light weight and high strength of a shoulder against an external force and are easy to peel off a label.

  In order to solve the above problems, the present invention provides a plastic bottle having a mouth portion, a shoulder portion, a trunk portion, and a bottom portion sequentially in the axial direction, wherein the trunk portion is adjacent to the plurality of wall portions and the circumferential direction. A square tube portion comprising corner portions connecting the matching wall portions; a label is packaged on the square tube portion; and the plastic bottle extends between the shoulder portion and the body portion in the circumferential direction. A first ridge line, the first ridge line is located closest to the body portion in the corner portion, and the shoulder portion protrudes toward the outside of the plastic bottle, and the circumference in the corner portion is It has the 2nd ridgeline extended in the said axial direction from the center of a direction, It is characterized by the above-mentioned.

  Further, a third protrusion protruding toward the outside of the plastic bottle is provided between the mouth side of the second ridge line and the boundary between the wall portion and the corner portion of the first ridge line. A ridge line is formed, and a fan-shaped sink panel having the second ridge line that bisects a central angle is formed on the shoulder portion in the region above the corner portion.

  Further, the sink panel is curved outward of the plastic bottle.

  Furthermore, the label is a shrink label.

  Furthermore, the filling body according to the present invention is constituted by the plastic bottle described above and a liquid to be filled.

  According to the present invention, in the plastic bottle having the mouth portion, the shoulder portion, the body portion, and the bottom portion in the axial direction, the body portion is a corner that connects the plurality of wall portions and the wall portions adjacent in the circumferential direction. A square tube portion, a label is wrapped around the square tube portion, and the plastic bottle has a first ridge line extending in a circumferential direction between the shoulder portion and the body portion, and the first ridge line Is located on the most barrel side in the corner portion, and the shoulder portion has a second ridge line that protrudes toward the outside of the plastic bottle and extends in the axial direction starting from the circumferential center of the corner portion. It is possible to provide a rectangular plastic bottle that has both the high performance and the high strength of the shoulder against external force and is easy to peel off the label.

  Further, a third ridge line protruding toward the outside of the plastic bottle is formed between the mouth side of the second ridge line and the boundary between the wall portion and the corner portion of the first ridge line. According to the structure in which the fan-shaped sinking panel having the second ridge line that bisects the central angle is formed on the shoulder portion in the region above the portion, the light weight and the higher strength of the shoulder portion with respect to external force are achieved. It is possible to provide a square-shaped plastic bottle that has both the label and the label easily peeled off.

  Further, according to the configuration in which the sink panel is curved to the outside of the plastic bottle, it is possible to provide a rectangular plastic bottle having both light weight and high strength of the shoulder against an external force and easy to peel off the label. Can do.

  Furthermore, according to the configuration in which the label is a shrink label, the present invention provides a square plastic bottle that has both light weight and high strength of a shoulder against an external force and that is easy to peel off a widely used shrink label. be able to.

  Furthermore, since the filling body according to the present invention is composed of the above-described plastic bottle and the liquid to be filled, it has both lightness and high strength of the shoulder against external force, and the corner where the label is easy to peel off. A filling body using a plastic bottle of a mold can be provided.

It is the front view by which the PET bottle as an example of the plastic bottle which concerns on this embodiment was shown. It is a top view of a PET bottle. It is a bottom view of a PET bottle. It is the front view to which the bottom part of the PET bottle was expanded. It is the front view by which the PET bottle which concerns on a modification was shown. It is a front view of the PET bottle of Comparative Example 1 and Comparative Example 2.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, the configuration of the plastic bottle according to the present embodiment will be described in detail. FIG. 1 is a front view showing a PET bottle 1 as an example of a plastic bottle according to the present embodiment, and FIG. 2 is a top view of the PET bottle 1. The PET bottle 1 has a mouth portion 10, a shoulder portion 20, a trunk portion 30, and a bottom portion 40 in that order in the axial direction. The illustrated PET bottle 1 is a so-called square bottle having a substantially rectangular tube shape having a plurality of wall portions 31 and a corner portion 32 connecting the wall portions 31 adjacent to each other in the circumferential direction of the PET bottle 1. is there.

  In the following, for convenience of explanation, the mouth portion 10 in which the contents are filled into the container in the state of FIG. 1 that is upright so that the axial direction of the PET bottle 1 extends vertically will be referred to as the top. The PET bottle 1 has an overall height H1 from the bottom 40 to the mouth 10.

  The mouth portion 10 serves as a filling port and a spout for the contents, and the PET bottle 1 is sealed by attaching a lid (not shown) to the mouth portion 10. The mouth portion 10 may be crystallized until it is colored white by heating in a so-called crystallization apparatus so as to have heat resistance necessary for filling the contents at high temperature.

  The upper side of the shoulder portion 20 is continuous with the mouth portion 10, while the lower side is continuous with the trunk portion 30. The shoulder 20 is configured in a truncated pyramid shape that extends in the radial direction of the PET bottle 1 from the upper side to the lower side in the axial direction.

  The PET bottle 1 has a ridge line 21 (first ridge line) extending in the circumferential direction between the shoulder portion 20 and the trunk portion 30. The ridge line 21 has a function of absorbing the axial load of the PET bottle 1. The ridge line 21 undulates in the axial direction, and is located closest to the trunk portion 30 in the corner portion 32. If the shoulder portion 20 in the region above the corner portion 32 is left as it is, it is easy to bend due to the axial load. However, the ridgeline 21 is dispersed without being concentrated at a portion where the ridgeline 21 is easily bent at the corner portion 32 due to the configuration located closest to the body portion 30, and the buckling strength of the PET bottle 1 is increased.

  The shoulder 20 is formed with a plurality of flat cut surfaces. And the side which becomes the boundary of these cut surfaces mainly functions as a support | pillar with respect to the load of the axial direction of the PET bottle 1 by extending in an axial direction.

  On the wall 31, an isosceles triangular region that is long in the axial direction with the ridge line 21 as a base is formed by a ridge line 22 that protrudes toward the outside of the PET bottle 1. Further, inside the isosceles triangle region, three triangular panels are formed by the three ridge lines 23 protruding toward the inside of the PET bottle 1. By configuring the shoulder 20 in the region above the wall 31 in this way, the strength against the axial and radial loads of the PET bottle 1 is increased, and the pressure inside the PET bottle 1 is changed. In some cases, the shape is maintained without being deformed.

  Furthermore, the shoulder portion 20 has a ridge line 24 (second ridge line) that protrudes toward the outside of the PET bottle 1 and extends in the axial direction starting from the circumferential center of the corner portion 32. The ridge line 24 is easily recessed inside the PET bottle 1 when pressed. Furthermore, a ridge line 25 (third ridge line) that protrudes toward the outside of the PET bottle 1 is also formed between the mouth 10 side of the ridge line 24 and the boundary between the wall portion 31 and the corner portion 32 of the ridge line 21. Is formed. Accordingly, a fan-shaped sink panel 26 having a ridge line 24 that bisects the central angle is formed on the shoulder 20 in the region above the corner portion 32. The ridge line 25 prevents the deformation when the ridge line 24 is pressed from spreading to a region outside the fan shape.

  The body 30 is packaged with a label such as a shrink label or a roll label on which information on the contents of the PET bottle 1 or a pattern for improving the design is printed. A biaxially stretched polystyrene film or the like having good heat shrinkability is used for the shrink label attached by heat shrinkage. Since the shrink label is made of a material different from that of the PET bottle 1, it is separated when it is recycled after the PET bottle 1 is used. Since the shrink label is mainly attached to the corner portion 32, the shrink label is easily removed by removing the catch at the corner portion 32. When the ridge line 24 is pushed, a gap is formed between the PET bottle 1 and the label in the vicinity of the corner portion 32 so that the label can be easily grasped, and the catch of the corner portion 32 is partially removed, and the label is easily peeled off. be able to.

  A plurality of cut surfaces formed on the shoulder portion 20 illustrated in FIG. 1 and the like are formed in a flat plate shape, and are not curved outside or inside the PET bottle 1. However, if the shoulder portion 20, particularly the fan-shaped sinking panel 26 is configured to be curved outwardly of the PET bottle 1, a wider gap is formed between the PET bottle 1 and the label, making the label easier. Can be peeled off.

  Although the shoulder 20 is not limited to the above-described configuration, it is preferable that the shoulder 20 has a ridge line 21 and a ridge line 24 in terms of the strength and shape maintaining function of the PET bottle 1 and the ease of peeling off the label.

  The body portion 30 has an upper corner tube portion 50u and a lower side corner tube portion 50d as a corner tube portion including a wall portion 31 and a corner portion 32, and an upper corner tube portion 50u and a lower side corner tube portion 50d. And a cylindrical portion 60 having a circular cross section perpendicular to the axial direction.

  FIG. 3 is a bottom view of the PET bottle 1. The upper rectangular tube portion 50u and the lower rectangular tube portion 50d illustrated in FIG. 1, FIG. 2, FIG. 3, etc. each have four wall portions 31 and four corner portions 32 having the same shape. doing. The corner portion 32 is curved outward in the radial direction. Both the upper and lower square tube portions 50u and 50d have the same vertical dimension in the upper and lower directions, and have a substantially regular square tube shape as a whole. The upper rectangular tube portion 50u and the lower rectangular tube portion 50d have a shape close to a cylinder by having the corner portion 32 curved outward, and the buckling strength is improved.

  Each of the upper corner tube portion 50u and the lower corner tube portion 50d is configured to have a diagonal distance D1 and a facing distance D2. The diagonal distance D1 is larger than the facing distance D2. The diagonal distance D1 is 84.5 mm, for example, and the facing distance D2 is 77.1 mm, for example. By forming the facing distance D2 of the upper rectangular tube portion 50u and the lower rectangular tube portion 50d to be the same, the respective wall portions 31 of the upper rectangular tube portion 50u and the lower rectangular tube portion 50d serve as a ground contact portion. The PET bottle 1 can be stably placed with the axial direction being horizontal.

  The upper rectangular tube portion 50u and the lower rectangular tube portion 50d have a plurality of annular circumferential grooves 51 that are recessed inward in the radial direction and cross the wall portion 31 and the corner portion 32 in the circumferential direction. The circumferential groove 51 has a substantially rounded square cross-sectional shape in the horizontal direction and a substantially tapered shape having a flat bottom surface in the vertical cross-sectional shape. However, the shape of the vertical cross section of the circumferential groove 51 may be an arc shape or a V shape. The circumferential groove 51 has a function of increasing the side wall strength, which is the strength that can withstand the load in the radial direction. And the ease of attachment of the label to the upper square tube part 50u improves because the side wall intensity | strength of the upper square tube part 50u increases. Furthermore, the circumferential groove 51 functions as a cushion against an axial load and has a function of preventing the body portion 30 from buckling.

  The depth of the circumferential groove 51 is substantially constant in the wall portion 31. On the other hand, the circumferential groove 51 is formed in the corner portion 32 so that the depth is minimized at the center in the circumferential direction. The depth of the circumferential groove 51 is different between the wall portion 31 and the corner portion 32, and the depth at the wall portion 31 is greater than the corner portion 32.

  The circumferential groove 51 configured in this manner has a function of increasing the side wall strength in the wall portion 31 and preventing buckling against an axial load, and reducing the amount of compressive deformation with respect to the axial load at the corner portion 32. Have Since the side wall strength is increased in the wall portion 31, the PET bottle 1 can be stably loaded sideways. The circumferential groove 51 has a function of preventing the load from being concentrated on the corner portion 32 and increasing the buckling strength of the body portion 30. Furthermore, since the circumferential groove 51 has a small depth at the corner portion 32 having a distance from the center of the PET bottle 1 in the radial direction, the circumferential groove 51 does not have a shape with severe irregularities and has good shapeability.

  Although the circumferential groove 51 may be formed with a constant width in the circumferential direction, the circumferential groove 51 is formed so that the width at the center in the circumferential direction of the wall portion 31 is maximized. If the width of the circumferential groove 51 is too large, the strength against the axial load decreases and the amount of compressive deformation increases. Therefore, the circumferential groove 51 has a larger width at the wall portion 31 than at the corner portion 32. The circumferential groove 51 has a function of increasing the rigidity of the body portion 30 by being configured in this way. Furthermore, since the circumferential groove 51 has a large width at the wall portion 31 having a large depth, the circumferential groove 51 does not have a shape with severe irregularities and has good shapeability.

  Four circumferential grooves 51a, 51b, 51c, and 51d are formed in the upper rectangular tube portion 50u in order from the upper side in the axial direction. Two circumferential grooves 51e and 51f are formed in the lower rectangular tube portion 50d in order from the upper side in the axial direction. The circumferential groove 51 is composed of three types having different depth and width dimensions. The circumferential groove 51a and the circumferential groove 51f, the circumferential groove 51b and the circumferential groove 51c, and the circumferential groove 51d and the circumferential groove 51e have the same dimensions. The depth of the circumferential groove 51 is circumferential groove 51d> circular groove 51a> circumferential groove 51b, and the circumferential groove 51 width is circumferential groove 51d> circular groove 51a> circular groove 51b.

  The peripheral groove 51a and the peripheral groove 51d increase the side wall strength of the upper rectangular tube portion 50u not only in the vicinity of each groove but also to the region between the peripheral groove 51a and the peripheral groove 51d. Accordingly, the depth and width dimensions of the circumferential groove 51b and the circumferential groove 51c can be reduced. And since the unevenness | corrugation of the upper side square cylinder part 50u is suppressed, it becomes difficult to produce the external appearance defect when a shrink label is mounted | worn, for example, and it can improve manufacturing efficiency and the display effect (advertisement effect) by a label.

  Here, four circumferential grooves 51a, 51b, 51c, and 51d are formed in the upper rectangular tube portion 50u, and two circumferential grooves 51e and 51f are formed in the lower rectangular tube portion 50d. An example has been shown. However, the number is not particularly limited, and the number is appropriately designed according to the vertical width of the upper corner tube portion 50u and the lower corner tube portion 50d, the depth and width of the groove, and the like. Furthermore, all the circumferential grooves 51 may be designed to have the same depth and width.

  The cylindrical portion 60 has a constricted portion 61. The neck portion 61 is formed by narrowing the body portion 30 in the radial direction. The constricted portion 61 is easy to grip because the waistline is short. Therefore, the constricted portion 61 functions as a gripping portion, and can easily hold the PET bottle 1.

  The constricted portion 61 has a rib 62 extending in the axial direction. The rib 62 protrudes toward the outside of the PET bottle 1. The rib 62 has a function as a support for both the axial and radial loads of the PET bottle 1. A plurality of ribs 62 are arranged in the circumferential direction of the constricted portion 61. The constricted part 61 in which the plurality of ribs 62 are arranged is improved in strength and hardly deformed, and the PET bottle 1 can be easily held. Further, the rib 62 can be applied to the grasped finger and can easily hold the PET bottle 1.

  At the upper end of the constricted portion 61, adjacent ribs 62 are connected by an upper side 63. The upper side 63 is curved in an arc shape toward the upper side. Similarly, adjacent ribs 62 are connected by a lower side 64 at the lower end of the constricted portion 61. The lower side 64 is curved in an arc shape toward the lower side. By forming the upper side 63 and the lower side 64, the cylindrical portion 60 is not easily deformed, and the PET bottle 1 can be easily held. Furthermore, the curved upper side 63 and the lower side 64 can absorb the axial load of the PET bottle 1 and increase the buckling strength. Two adjacent ribs 62 are taken as opposite sides, and an oblong panel 65 is formed by the opposite sides, the upper side 63, and the lower side 64. Therefore, the constricted portion 61 is formed in a cylindrical shape by connecting a plurality of panels 65 curved radially inward in the circumferential direction.

  In addition, the area | region above the upper side 63 and the area | region below the lower side 64 are the cylindrical shapes of the same diameter up and down.

  The panel 65 including the ribs 62 has a curved shape so that the diameter decreases toward the center in the axial direction starting from the upper side 63 and the lower side 64. And the rib 62 is comprised so that the distance from the center of radial direction may become the largest in the arbitrary cross sections orthogonal to the axial direction of the constriction part 61. FIG. That is, the cross section of the constricted portion 61 is a polygon having the rib 62 as a vertex. The PET bottle 1 configured in this manner has both lightness and high strength against external force, and is easy to hold.

  In addition, the polygonal side formed in the cross section of the constricted part 61 may be a curved shape curved toward the inside in the radial direction, may be a straight shape, or a curved line curved toward the outside. It may be in the shape. However, when the side of the cross section of the constricted portion 61 is curved inward, the PET bottle 1 becomes easier to hold.

  As illustrated in FIG. 1 and the like, the rib 62 preferably has a twist in the circumferential direction. Since the rib 62 has a twist, it becomes easier to catch the finger gripped, and the PET bottle 1 becomes easier to hold. Furthermore, since the rib 62 has a twist, the axial load is dispersed in the circumferential direction, and the buckling strength of the PET bottle 1 can be increased.

  The rib 62 has an inclination of an angle θt with respect to the vertical line L. If the angle θt is too large, the function of the rib 62 as a support is reduced. Therefore, the angle θt is preferably 0 ° or more and 60 ° or less from the viewpoint of maintaining the strength of the PET bottle 1 while having ease of holding. Furthermore, the angle θt is more preferably 20 ° or more and 40 ° or less from the viewpoint of further improving the ease of holding. On the other hand, from the viewpoint of further improving the buckling strength, the angle θt is more preferably 0 ° or more and 35 ° or less.

  The rib 62 may not be twisted and may be counterclockwise, but may be more easily held clockwise as illustrated in FIG. 1 and the like.

  If the number of the panels 65 is too small, the buckling strength of the PET bottle 1 tends to be insufficient. On the other hand, when the number of the panels 65 is too large, the ease of holding the PET bottle 1 is lowered. Therefore, the number of the panels 65 is preferably 5 or more and 12 or less, and more preferably 6 or more and 8 or less from the viewpoint of improving the ease of holding while maintaining the strength of the PET bottle 1. The panel 65 of PET bottle 1 illustrated by FIG. 1 etc. is comprised by six.

  If the panel 65 is configured with an odd number, the rib 62 and the surface of the panel 65 face each other at both ends in the radial direction of the constricted portion 61. On the other hand, if the panel 65 is an even number, the surfaces of the panel 65 face each other. When the surfaces of the panel 65 are opposed to each other, the length in the diameter direction of the constricted portion 61 is shortened and is easily held. Therefore, the panel 65 is preferably configured with an even number.

  In addition, it is preferable that the several panel 65 is made into the same shape from a viewpoint which prevents that the stress with respect to the load to PET bottle 1 concentrates on the specific location of the constriction part 61, and a ease of holding falls.

  Furthermore, when the lightness of the PET bottle 1 is not a problem, the panel 65 may be divided into two parts in the axial direction.

  The axial distance H2 of the constricted portion 61 may be designed based on the width of the hand from the second finger to the fifth finger. Since the entire palm covers the constricted portion 61, the PET bottle 1 can be stably held. If the distance H2 in the axial direction of the constricted portion 61 is too short, a finger protrudes from the constricted portion 61 and the ease of holding the PET bottle 1 decreases. On the other hand, if the axial distance H2 of the constricted portion 61 is too long, it is difficult to maintain the strength of the PET bottle 1. Therefore, from the viewpoint of maintaining strength while having the ease of holding the PET bottle 1, the constricted portion 61 preferably has an axial distance H2 of 50 mm or more and 100 mm or less, and 55 mm or more and 85 mm or less. It is more preferable that

  The PET bottle 1 is configured to have a sufficient distance H2 in the axial direction of the constricted portion 61. The constricted portion 61 configured as described above shows a strong clue for guiding the constricted portion 61 to be handled as a gripping portion. Therefore, the PET bottle 1 is configured such that the constricted portion 61 can be handled as a gripping portion without explanation.

  If the ratio value (H2 / H1) of the axial distance H2 of the constricted portion 61 to the total height H1 of the PET bottle 1 is too small, the grip portion becomes small and the PET bottle 1 becomes difficult to hold. On the other hand, if H2 / H1 is too large, the upper rectangular tube portion 50u becomes small and the area for displaying the label becomes narrow. Furthermore, if H2 / H1 is too large, it will be difficult to maintain the strength of the PET bottle 1. Therefore, the constricted portion 61 preferably has a ratio value (H2 / H1) of the axial distance H2 of the constricted portion 61 to the total height H1 of the PET bottle 1 of 0.15 or more and 0.45 or less.

  The constricted portion 61 is formed with a diameter reduced so as to be the minimum body diameter D4 with respect to the maximum body diameter D3 having the same diameter as the cylindrical portion 60. When the PET bottle 1 is formed by blow molding, the constricted part 61 can be made thicker by being positioned more inside in the radial direction of the PET bottle 1. As the constricted portion 61 is thicker, the strength is increased and the structure can be maintained. And it is preferable that the thickness of the constriction part 61 is 0.15 mm or more and 0.50 mm or less.

  The value (D4 / D3) of the minimum body diameter D4 to the maximum body diameter D3 of the constricted part 61 is preferably 0.65 or more and 0.95 or less, and is 0.70 or more and 0.85 or less. It is more preferable. With such a configuration, the ease of holding the PET bottle 1 can be improved and the buckling strength can be effectively increased. If the ratio of the minimum body diameter D4 to the maximum body diameter D3 (D4 / D3) is too large, the ease of holding the PET bottle 1 will be difficult to improve. On the other hand, if the value of the ratio (D4 / D3) of the minimum body diameter D4 to the maximum body diameter D3 is too small, the stress with respect to the axial load of the PET bottle 1 is excessively concentrated near the minimum body diameter D4. A sufficient buckling strength cannot be obtained.

  The PET bottle 1 has a constricted portion 61 with a reduced diameter and a rib 62 extending in the axial direction, and is configured to improve ease of holding while sufficiently securing a buckling strength.

  There is no limitation on the size relationship between the maximum body diameter D3 of the constricted portion 61 and the facing distance D2 of the upper and lower angular tube portions 50u and 50d. However, from the viewpoint of the loading efficiency of the PET bottle 1 and the like, the cylindrical portion 60 is preferably an inscribed circle of the upper rectangular tube portion 50u and the lower rectangular tube portion 50d. That is, it is preferable that the facing distance D2 and the maximum body diameter D3 have the same length.

  The position of the cylindrical portion 60 in the axial direction with respect to the upper rectangular tube portion 50u and the lower rectangular tube portion 50d is not limited to the configuration shown in FIG. For example, the cylindrical part 60 may be arranged on the upper square tube part 50u side from the position shown in FIG. By being configured in this manner, the area to which the label is attached is reduced, but the contents are more easily poured out.

  It is preferable that the upper rectangular tube portion 50u, the lower rectangular tube portion 50d, and the cylindrical portion 60 are connected via a connecting groove 70 and a connecting groove 75 that are recessed in the radial direction and extend in the circumferential direction, respectively. The connecting groove 70 and the connecting groove 75 have a function of receiving an axial load as a cushion and preventing bending of the connecting portion. Furthermore, the connecting groove 70 and the connecting groove 75 have a function of increasing the side wall strength in the vicinity of the connecting portion. The connecting groove 70 and the connecting groove 75 have a circular cross-sectional shape in the horizontal direction and a substantially tapered shape having a flat bottom surface in the vertical cross-sectional shape. The connecting groove 70 and the connecting groove 75 may have an arc shape or a V-shaped cross section in the vertical direction.

  If the depth of the connecting groove 70 and the connecting groove 75 is too shallow, it is difficult to increase the side wall strength. On the other hand, if the depth of the connecting groove 70 and the connecting groove 75 is too deep, the shapeability at the time of molding the PET bottle 1 tends to be lowered. The depth of the connecting groove 70 and the connecting groove 75 is preferably 0.005 or more and 0.07 or less, and more preferably 0.03, with respect to the maximum body diameter D3.

  If the width of the connecting groove 70 and the connecting groove 75 is too wide, it is difficult to increase the side wall strength. On the other hand, if the widths of the connecting groove 70 and the connecting groove 75 are too narrow, the shapeability at the time of molding the PET bottle 1 tends to be lowered. The width of the connecting groove 70 and the connecting groove 75 is preferably such that the ratio of the depth of the connecting groove 70 and the connecting groove 75 is not less than 0.5 and not more than 5.0.

  Since the slope of the surface on the side of the upper rectangular tube portion 50u of the connecting groove 70 and the side of the lower rectangular tube portion 50d of the connecting groove 75 is uniform, this surface is just chamfered at the corner portion 32. It has a shape. Therefore, the axial load is dispersed without concentrating on the corner portion 32 that is easily bent, and the buckling strength of the PET bottle 1 is increased.

  FIG. 4 is an enlarged front view of the bottom 40 of the PET bottle 1. The bottom part 40 is continued to the lower side of the lower rectangular tube part 50d of the body part 30. The bottom portion 40 has a corner portion 41, a bottom wall 42, and a dome 43. The corner portion 41 is curved toward the lower side in the axial direction of the PET bottle 1 and the outer side in the radial direction. The substantially flat annular bottom wall 42 extends in a direction perpendicular to the body portion 30 and serves as a ground contact surface of the PET bottle 1. The dome 43 is formed in a hollow hemispherical shape that curves toward the inside (the upper side in the axial direction) of the PET bottle 1. The dome 43 has a function of preventing deformation due to changes in the temperature of the contents of the PET bottle 1 and the internal pressure.

  The dome 43 is inclined with respect to the ground plane. If the angle of inclination θd at the peripheral edge of the dome 43 is too small, it will be difficult to prevent deformation. On the other hand, when the inclination angle θd of the dome 43 is too large, the shapeability at the time of molding the PET bottle 1 tends to be lowered. Therefore, it is preferable that the angle θd of the inclination of the dome 43 is not less than 8 ° and not more than 18 ° from the viewpoint of effectively dispersing the pressure and the like to prevent deformation and improving the shapeability.

  The dome 43 further includes a rib 44. The number of the ribs 44 illustrated in FIG. 3 is four, and each extends radially in a bottom view. The rib 44 has a function of reinforcing the dome 43. The rib 44 can be formed by making the angle of inclination different from that of the dome 43. At this time, if the ribs 44 are formed with a steeper slope on the peripheral end side of the dome 43, whitening due to overstretching and a decrease in the shapeability of the PET bottle 1 are likely to occur. Therefore, it is preferable that the rib 44 has a gentler inclination on the peripheral end side of the dome 43.

  The bottom portion 40 has an annular rising portion 45 that extends from the bottom wall 42 located on the outer peripheral side toward the peripheral end of the dome 43 and extends larger than the inclination of the dome 43. The rising portion 45 has a function of preventing the bottom portion 40 from protruding beyond the ground surface when a large pressure is applied from the outside of the PET bottle 1. For example, when the PET bottle 1 conveyed through the filling system collides with another PET bottle 1 and pressure is applied, and the bottom portion 40 protrudes, the PET bottle 1 extends in the axial direction. Cause clogging. This means that the degree of necessity of measures increases as the PET bottle 1 becomes lighter and its wall thickness becomes thinner.

  If the bottom portion 40 becomes too thin, it becomes difficult to maintain the structure when the pressure inside the PET bottle 1 changes. On the other hand, if it becomes too thick, weight reduction of the PET bottle 1 will be hindered. Therefore, from the viewpoint of maintaining the structure of the bottom 40 while realizing weight reduction of the PET bottle 1, the thickness of the bottom 40 is preferably 0.10 mm or more and 0.35 mm or less.

  One of the causes that the bottom portion 40 protrudes is that the vicinity of the peripheral edge of the dome 43 is bent so that the bottom portion 40 is inverted so as to protrude from the ground surface. However, the rising portion 45 disperses the deformation direction when pressure is applied from the axial direction to the radial direction due to the large inclination. Further, the rising portion 45 is stopped in a range where it does not protrude from the ground surface even if it is deformed by increasing the axial distance from the ground surface. And the rising part 45 raises an intensity | strength by making the dome 43 and an inclination become discontinuous. By having these functions, the rising portion 45 effectively prevents the bottom portion 40 from protruding.

  Here, when the inclination angle θr of the rising portion 45 is too large, whitening due to overstretching and a decrease in the shapeability of the PET bottle 1 are likely to occur. Therefore, the inclination angle θr of the rising portion 45 is preferably 30 ° or more and 65 ° or less.

  Furthermore, if the axial distance H3 of the rising portion 45 is too large, the rising portion 45 becomes a bending point. Therefore, the axial distance H3 of the rising portion 45 is preferably 4 mm or more and 9 mm or less.

  The PET bottle 1 has the rising portion 45, so that the degree of freedom in designing the shape of the dome 43 is increased. For example, the PET bottle 1 may not have the rib 44.

  Here, a shape maintaining function of the dome 43 can be enhanced by providing a groove extending radially from the dome 43 to the bottom wall 42. However, the PET bottle 1 having a gap in the bottom wall 42 cannot be applied to a method in which the bottom 40 that is frequently used as a filling system is sucked and conveyed.

  On the other hand, the bottom wall 42 is configured as a flat surface, and the PET bottle 1 that does not have a groove or the like recessed toward the upper side in the axial direction can be applied to a system in which the bottom 40 is sucked and conveyed, High versatility. Therefore, the PET bottle 1 can maintain the structure of the bottom 40 while having both light weight and high versatility.

  Note that the bottom 40 is not limited to the example shown in FIG. 3 and the like, and may be configured so as not to be deformed downward even when positive pressure is applied in a state in which it is easily deformed by heat. As a result, the full capacity of the PET bottle 1 can be increased and the change in internal pressure can be prevented from becoming larger. The dome 43 is designed to be maintained at least higher than the ground plane of the PET bottle 1 even if it is deformed by heat. Thus, the bottom portion 40 is prevented from projecting outward (downward) from the bottom wall 42, and rattling or overturning of the PET bottle 1 can be prevented.

  As described above, the PET bottle 1 has the mouth portion 10, the shoulder portion 20, the trunk portion 30, and the bottom portion 40, and the trunk portion 30 includes a plurality of wall portions 31 and walls that are adjacent in the circumferential direction. The upper rectangular tube portion 50u and the lower rectangular tube portion 50d composed of the corner portions 32 connecting the portions 31 and the upper rectangular tube portion 50u and the lower rectangular tube portion 50d are divided in the axial direction, and crossing perpendicular to the axial direction. The cylindrical portion 60 has a constricted portion 61 in which the body portion 30 is squeezed in the radial direction. The constricted portion 61 is convex outward in the radial direction and extends in the axial direction. The rib 62 extends, and the rib 62 is configured such that the distance from the center in the radial direction is maximized in an arbitrary cross section of the constricted portion 61. According to such a configuration, it is possible to provide a large and square PET bottle 1 that has both light weight and high strength against external force and is easy to hold.

  Further, the bottom 40 of the PET bottle 1 has a hollow hemispherical dome 43 that curves toward the inside of the PET bottle 1, and the bottom 40 is directed from the bottom wall 42 located on the outer peripheral side toward the peripheral end of the dome 43. And an annular rising portion 45 extending larger than the inclination of the dome 43. According to such a configuration, it is possible to provide a large-sized PET bottle 1 having both light weight and high strength against the external force of the bottom portion 40.

  Furthermore, it has the ridgeline 21 extended in the circumferential direction between the shoulder part 20 and the trunk | drum 30, and the ridgeline 21 is located in the side of the trunk | drum 30 in the corner part 32 most. According to such a configuration, it is possible to provide the PET bottle 1 having both lightness and high strength in the shoulder portion 20.

  The PET bottle 1 according to this embodiment is not limited by size, and can be applied to various sizes. However, it is preferable that the bottle is larger because the effect of the configuration of the PET bottle 1 according to this embodiment is more exhibited. For example, the inner volume of the PET bottle 1 is preferably 680 ml or more and 2500 ml or less, and more preferably 900 ml to 2000 ml. The total height H1 of the PET bottle 1 may be 190 mm or more and 320 mm or less, and the facing distance D2 of the body 30 may be 65 mm or more and 100 mm or less.

  Furthermore, the PET bottle 1 according to the present embodiment can be suitably used for light weight bottles. For example, the mass of the PET bottle 1 is preferably 20 g or more and less than 30 g for 1000 ml, and 25 g or more and less than 35 g for 2000 ml. And in particular, from the viewpoint of maintaining the strength of the PET bottle 1 while increasing the amount of absorption of changes in internal pressure, the value of the ratio of the mass to the internal volume of the PET bottle 1 is 0.0125 g / ml or more, It is preferable that it is 0.0300 g / ml or less.

  Examples of the material of the plastic bottle exemplified by the PET bottle 1 include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, polypropylene, and other polyolefins, ethylene-vinyl alcohol copolymers, plants, and the like. Various plastics that can be blow molded, such as polylactic acid, can be used. However, the plastic bottle is preferably composed mainly of polyester such as polyethylene naphthalate, particularly polyethylene terephthalate. In addition, various additives such as a colorant, an ultraviolet absorber, a release agent, a lubricant, a nucleating agent, an antioxidant, and an antistatic agent are blended with the above-described resin within a range that does not impair the quality of the molded product. be able to.

  As the ethylene terephthalate thermoplastic resin constituting the PET bottle 1, most of the ester repeating portion, generally 70 mol% or more is occupied by ethylene terephthalate units, and the glass transition point (Tg) is 50 ° C. or higher and 90 ° C. The melting point (Tm) is preferably in the range of 200 ° C. or higher and 275 ° C. or lower. As an ethylene terephthalate thermoplastic polyester, polyethylene terephthalate is particularly excellent in terms of pressure resistance, but in addition to ethylene terephthalate units, it consists of dibasic acids such as isophthalic acid and naphthalenedicarboxylic acid, and diols such as propylene glycol. Copolyesters containing a small amount of ester units can also be used.

  Polyethylene terephthalate has the highest production volume among thermoplastic synthetic resins. The polyethylene terephthalate resin has various characteristics such as excellent heat resistance, cold resistance, chemical resistance, and wear resistance. Furthermore, polyethylene terephthalate resin has a lower proportion of petroleum in its raw materials than other plastics, and can be recycled. Thus, according to the structure which has a polyethylene terephthalate as a main component, a material with much production amount can be used and the outstanding various characteristic can be utilized.

  Polyethylene terephthalate is obtained by condensation polymerization of ethylene glycol (ethane-1,2-diol) and purified terephthalic acid. As a polymerization catalyst for polyethylene terephthalate, at least one of a germanium compound, a titanium compound, and an aluminum compound is preferably used. By using these catalysts, it is possible to form a container having higher transparency and excellent heat resistance than using an antimony compound.

  A plastic bottle can be produced by blow-molding a preform in which the above-described material is injection-molded. And PET bottle 1 as an example of the plastic bottle which concerns on this embodiment is produced by using a polyethylene terephthalate as a material. And the filling body is comprised by the PET bottle 1 and the liquid with which it fills. The filling body is manufactured by filling a liquid such as a beverage or a seasoning from the mouth portion 10 of the PET bottle 1 and sealing with a lid (not shown) attached to the mouth portion 10.

  Next, the configuration of the plastic bottle according to the modification will be described in detail. FIG. 5 is a front view showing a PET bottle 100 according to a modification. The PET bottle 100 has the same configuration as the PET bottle 1 except that it has ribs 162 different from the ribs 62 of the PET bottle 1. That is, the PET bottle 100 has the mouth part 10, the shoulder part 20, the trunk | drum 130, and the bottom part 40 in order in the axial direction. Further, the body portion 130 divides the upper and lower rectangular tube portions 50u and 50d, the upper and lower rectangular tube portions 50u and 50d in the axial direction, and has a cross section orthogonal to the axial direction. A circular cylindrical portion 160. The cylindrical portion 160 has a constricted portion 161.

  The constricted portion 161 has a rib 162 extending in the axial direction. The rib 162 protrudes toward the outside of the PET bottle 100. The rib 162 has a function as a support for both the axial and radial loads of the PET bottle 100. A plurality of ribs 162 are arranged in the circumferential direction of the constricted portion 161. The constricted part 161 in which the plurality of ribs 162 are arranged is improved in strength and hardly deformed, and the PET bottle 100 can be easily held. Further, the rib 162 can be applied to the grasped finger and can easily hold the PET bottle 100.

  The upper and lower ends of the constricted portion 161 do not have a configuration corresponding to the upper side 63 and the lower side 64 of the PET bottle 1 that connects the adjacent ribs 162. However, the PET bottle 100 having the ribs 162 has both lightness and high strength against external force and is easy to hold, and has the same effect as the PET bottle 1.

  The PET bottle 1 according to this embodiment may have a configuration different from that described above except for the constricted portion 61 and the constricted portion 161.

  Hereinafter, the present disclosure will be described in more detail and specifically with reference to examples. However, the present disclosure is not limited to the following examples.

<Material and manufacturing method>
[Example 1]
A PET bottle 1 shown in FIG. 1 and the like having a filling capacity of 990 ml made of 24 g of polyethylene terephthalate was used. The maximum body diameter D3 of the constricted portion 61 of the PET bottle 1 was 77.1 mm, and the minimum body diameter D4 was 63.3 mm. The PET bottle 1 was filled with 950 ml of water.

  In the PET bottle 1 according to the first embodiment, the body portion 30 includes a plurality of wall portions 31 and an upper corner tube portion 50u including a corner portion 32 connecting the wall portions 31 adjacent in the circumferential direction, and a lower side corner tube portion 50d. And the upper rectangular tube portion 50u and the lower rectangular tube portion 50d are divided in the axial direction and have a circular cylindrical portion 60 having a circular cross section perpendicular to the axial direction. The cylindrical portion 60 has a constricted portion 61. The constricted portion 61 has a rib 62 extending in the axial direction, and the body portion 30 is squeezed in the radial direction. The rib 62 has a distance from the radial center in an arbitrary cross section of the constricted portion 61. It has the characteristics according to the present embodiment such as the maximum.

[Comparative Example 1]
Comparative Example 1 was the same as Example 1 except that the PET bottle 200 shown in FIG. 6 was used. In the PET bottle 200, the body portion 230 is formed in a square cylinder shape with a uniform waistline in the axial direction, and 13 circumferential grooves 251 are formed in the body portion 230. The PET bottle 200 did not have a configuration corresponding to the cylindrical portion 60 or the constricted portion 61 of the PET bottle 1. Therefore, the filler according to Comparative Example 1 did not have the characteristics according to the present embodiment.

[Comparative Example 2]
Comparative Example 2 was the same as Comparative Example 1 except that it was 28 g. Therefore, the filler according to Comparative Example 2 did not have the characteristics according to the present embodiment.

<Evaluation method>
(Lightweight)
It was determined whether weight reduction could be achieved by the mass of each PET bottle of Example 1, Comparative Example 1, and Comparative Example 2. In the determination of weight reduction, a threshold value was set to be greater than 24 g or less. Table 1 shows the results of evaluation of the lightness of each PET bottle, and is indicated by ◯: light weight and x: no light weight.

(Buckling strength test)
The buckling strength in the upright state of the PET bottles 1 and 200 was measured for each of the fillers of Example 1 and Comparative Examples 1 and 2. For the measurement of buckling strength, a tester manufactured by AGR, TOP LOAD, was used. A load was applied from above the mouth portion 10 at a constant speed, and the load at the stage of displacement by 5 mm was regarded as buckling strength. In the determination of the buckling strength, a value of 180 N or more or less was set as a threshold value. Table 1 shows the results of the evaluation of the buckling strength of each filler, and is indicated by ◯: with buckling strength and x: insufficient buckling strength.

(Monitoring survey)
Each packing body of Example 1, Comparative Example 1, and Comparative Example 2 was prepared, and the one with the best ease of holding was selected for the monitors of 100 people in their 20s to 70s. Items selected for each monitor were counted as one by one. Table 1 shows the total score.

(Comprehensive evaluation)
Based on the above-described lightness, buckling strength test, and monitoring survey, comprehensive evaluation of each PET bottle (each filler) of Example 1, Comparative Example 1, and Comparative Example 2 was performed. Table 1 shows the results of comprehensive evaluation. Comprehensive evaluation is described by (circle): favorable and x: no aptitude.

  The following points were derived from the examples described above. The PET bottle 1 (filler) according to Example 1 had a sufficient buckling strength while being configured to be lightweight. Many monitors supported their ease of holding.

  On the other hand, in Comparative Example 1, although the weight was reduced, the buckling strength was insufficient. When the weight reduction was slightly insufficient as in Comparative Example 2, the buckling strength was satisfied. And in the PET bottle 200 of the comparative example 1 and the comparative example 2, since it did not have a constriction, it was inferior in the point of the ease of holding.

  From the results of the above examples, it was shown that the PET bottle 1 and the filling body according to the present embodiment have sufficient buckling strength and are easy to hold even when the weight is reduced. Therefore, in this embodiment, it was shown that it is possible to provide a large and square PET bottle 1 and a filling body that have both lightness and high strength against external force and are easy to hold.

  The present disclosure can be suitably used for various plastic bottles filled with liquid as contents. However, the present disclosure is not limited to the above-described embodiments and examples. Plastic bottles of the present disclosure include, for example, various non-carbonated beverages such as water, green tea, oolong tea, black tea, coffee, fruit juice, and soft drinks, or seasonings such as soy sauce, sauce, mirin, edible oil, foods including alcoholic beverages, etc. Useful for containing detergents, shampoos, cosmetics, pharmaceuticals, and any other contents. In particular, the plastic bottle of the present disclosure is suitable for use in a large bottle whose weight is increased by a large amount of contents because the container is easy to hold.

1,100 PET bottle (plastic bottle)
10 mouth portion 20 shoulder portion 21 ridge line (first ridge line)
24 ridgeline (second ridgeline)
25 ridgeline (third ridgeline)
26 Sink panel 30, 130 Body 31 Wall part 32 Corner part 40 Bottom part 50u Upper square tube part (square tube part)

In order to solve the above problems, the present invention provides a plastic bottle having a mouth portion, a shoulder portion, a trunk portion, and a bottom portion sequentially in the axial direction, wherein the trunk portion is adjacent to the plurality of wall portions and the circumferential direction. A square tube portion comprising corner portions connecting the matching wall portions; a label is packaged on the square tube portion; and the plastic bottle extends between the shoulder portion and the body portion in the circumferential direction. A first ridge line, the first ridge line is located closest to the body portion in the corner portion, and the shoulder portion protrudes toward the outside of the plastic bottle, and the circumference in the corner portion is have a second ridge extending in the axial direction center of the direction in origin, the side of the mouth portion of the second ridge, with the wall portion of the first ridge of the boundary between the corner portion In between, it protrudes towards the outside of the plastic bottle A third ridgeline that, in the shoulder region on the corner portion, characterized in that the fan-shaped sink panel having a second edge line which bisects the center angle is formed.

According to the present invention, in the plastic bottle having the mouth portion, the shoulder portion, the body portion, and the bottom portion in the axial direction, the body portion is a corner that connects the plurality of wall portions and the wall portions adjacent in the circumferential direction. A square tube portion, a label is wrapped around the square tube portion, and the plastic bottle has a first ridge line extending in a circumferential direction between the shoulder portion and the body portion, and the first ridge line is most located on the side of the body portion at the corner portion, the shoulder portion have a second ridge extending axially starting from the circumferential direction of the center of the corner portion protrudes toward the outside of plastic bottles, the There is a third ridge line protruding toward the outside of the plastic bottle between the side of the mouth of the ridge line of 2 and the boundary between the wall part and the corner part of the first ridge line. A fan-shaped sinking panel having a second ridge line that bisects the central angle is provided on the shoulder of the region. Since There has been formed, it is possible to provide a lightweight, and has both a high strength of the shoulder portion against an external force, and the plastic bottle peel easily rectangular labels.

Claims (5)

In a plastic bottle having a mouth portion, a shoulder portion, a trunk portion, and a bottom portion sequentially in the axial direction,
The trunk is
A plurality of wall portions, and a rectangular tube portion including a corner portion connecting the wall portions adjacent in the circumferential direction;
A label is packaged on the square tube portion,
The plastic bottle is
Having a first ridge line extending in the circumferential direction between the shoulder and the body;
The first ridge line is located closest to the body portion in the corner portion,
The shoulder is
A plastic bottle characterized by having a second ridge line that protrudes toward the outside of the plastic bottle and extends in the axial direction starting from the circumferential center of the corner portion. A third ridge line protruding toward the outside of the plastic bottle is located between the mouth side of the second ridge line and the boundary between the wall portion and the corner portion of the first ridge line. 2. The plastic according to claim 1, wherein a fan-shaped sink panel having the second ridge line that bisects a central angle is formed on the shoulder portion of the region formed above the corner portion. Bottle. The plastic bottle according to claim 2, wherein the sinking panel is curved outward of the plastic bottle. The plastic bottle according to any one of claims 1 to 3, wherein the label is a shrink label. A plastic bottle according to any one of claims 1 to 4,
A filling body comprising a liquid to be filled.

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