JP2011057263A - Bottom structure of pressure resistance packaging container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bottom structure of a pressure resistance packaging container, in which a wrinkle generated on a leg of the pressure resistance packaging container can be restrained more effectively. <P>SOLUTION: The ratio of the maximum barrel diameter D of the pressure resistance packaging container 10 to the overall height HT of the pressure resistance packaging container 10 meets 0.30≤(D/HT)≤0.41 and the ratio of the bottom height HB from a grounding part 32 of the pressure resistance packaging container 10 to the starting part 21 of the bottom part 20 to the overall height HT of the pressure resistance packaging container 10 meets 0.13≤(HB/HT)≤0.18 and a first ditch 40 dented to the inside of the leg 30 is formed on a leg side face 31 along the circumference of the pressure resistance packaging container 10 and ranging over the whole length of the leg side face 31 and the first ditch 40 is formed at a position meeting 0.2HB<H1<HB from the grounding part 32 in the relation between the height H1 of the first ditch from the grounding part 32 of the pressure resistance packaging container 10 to the deepest portion 41 of the first ditch 40 and the bottom height HB from the grounding part 32 of the pressure resistance packaging container 10 to the staring part 21 of the bottom part 20. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a bottom structure of a pressure-resistant packaging container, and particularly relates to an improvement in the structure of the bottom part of a resin-made self-standing pressure-resistant packaging container.

  Generally, a resin container made of a polyester resin such as polyethylene terephthalate is frequently used as a pressure-resistant packaging container for soft drinks in which carbon dioxide gas is dissolved. In particular, in order to enhance pressure resistance, the container is formed into a rounded shape as a whole. Conventionally, from the viewpoint of pressure resistance, the bottom of the container is formed in a hemispherical shape, and a member called a base cup is separately bonded to the bottom to ensure the self-supporting of the container. Since then, the number of pressure-resistant packaging containers of the aforementioned style has decreased due to the reduction in the number of parts and the simplification of the manufacturing process.

  Instead of this, the pressure-resistant packaging container 100 provided with a so-called petaloid-shaped leg portion 130 has become predominantly dominant (see FIGS. 8 and 9). . The petaloid-shaped leg portion 130 has a self-supporting property and has a pressure resistance performance that disperses an internal pressure generated when a carbonated beverage or the like is filled. In the figure, reference numeral 111 is a container body, 112 is a container mouth, 120 is a bottom having a petaloid-shaped leg 130, 131 is a leg side surface of the leg 130, and 132 is a grounding part of the leg 130. .

  When the above-mentioned pressure-resistant packaging container 100 is filled with contents to which an internal pressure such as carbonated drink is applied, as shown in FIG. 10, the container surface 101 (see the solid line in the figure) constantly receives an internal pressure P10 caused by the contents. As a result, the tensile force P11 acts to expand (101A: see the two-dot chain line in the figure). This pulling force P11 concentrates on the ground contact portion 132 of the leg portion 130 due to the structure of the container. Therefore, even if the internal pressure P10 is dispersed by the petaloid-shaped leg portion 130, due to the passage of time or the height of the internal pressure, as shown in FIG. Deformation and shape defects may occur. These wrinkles W of the bottom part 120 and the leg part 120 are regarded as problems because they deteriorate the appearance of the packaging container and significantly impair the attractiveness of the product. Further, it has been pointed out that wrinkles deteriorate the stability of the packaging container and make it difficult to stand upright at the time of display at a store.

  As a countermeasure against the problem of wrinkle generation due to such internal pressure, as shown in FIG. 12, a groove part that indents inward of the container at the lower end part of the leg side part 131 above the grounding part 132 of the leg part 130 of the container. A pressure-resistant container in which 140 is disposed in the circumferential direction of the container and / or in the height direction of the container has been proposed (see Patent Document 1). In this figure, the same reference numerals as those in FIGS. 8 and 9 indicate the same configuration, and the description thereof is omitted.

  However, at present, the pressure-saving packaging container 100 including the bottom portion 120 having the petaloid-shaped legs 130 shown in FIGS. There is a need to reduce the amount of resin used in itself. The suppression of the amount of resin used reduces the weight of the container while reducing the thickness of the entire container. Therefore, the thickness of the grounding portion 132 between the container 100 and the floor in the leg portion 130 of the container bottom 120 is inevitably reduced, The problem that the intensity | strength of the container bottom part 120 falls generate | occur | produces.

  According to the pressure resistant container of Patent Document 1, it is pointed out that the effectiveness of forming the groove portion 140 at the lower end portion of the leg side surface portion 132 in the conventional container is shown. However, if the strength of the ground contact portion 132 is reduced by reducing the amount of resin used with the weight of the container, wrinkles will not occur if the groove portion 140 is simply disposed at the lower end portion of the leg side surface portion 131. It became clear that it was not enough to suppress. Thus, a bottom structure that can more effectively suppress the generation of wrinkles in a pressure-resistant packaging container has been newly demanded.

Japanese Patent No. 2595865

  This invention is made | formed in view of the said point, and provides the bottom part structure of the pressure | voltage resistant packaging container which can suppress the wrinkle which generate | occur | produces in the leg part of a pressure | voltage resistant packaging container more effectively.

  That is, the invention of claim 1 is a pressure-resistant packaging container in which a thermoplastic polyester-based resin composition is integrally provided with legs and a bottom for securing the self-supporting property of the container by stretch blow molding, and the bottom is a bottom hemisphere. The leg portion is formed of a curved pyramid trapezoidal shape including a leg side surface portion and a grounding portion continuous from the container body surface portion toward the bottom portion, and the leg portion is formed from the center of the bottom hemispherical portion. The central angle is equally divided in the circumferential direction of the pressure-resistant packaging container, and a plurality of the protrusions are arranged to protrude radially in the grounding direction of the pressure-resistant packaging container at predetermined intervals, and the legs are arranged adjacent to each other via a valley. In the bottom structure of the pressure-resistant packaging container, the ratio of the maximum body diameter (D) of the pressure-resistant packaging container to the total height (HT) of the pressure-resistant packaging container is 0.30 ≦ (D / HT) ≦ 0.41; The concerned The ratio of the bottom height (HB) from the grounding portion of the pressure-resistant packaging container to the origin of the bottom with respect to the total height (HT) of the pressure packaging container is 0.13 ≦ (HB / HT) ≦ 0.18 A first groove portion that fills and is recessed toward the inside of the leg portion is formed on the leg side surface portion along the circumferential direction of the pressure-resistant packaging container and over the length of the leg side surface portion. Between the first groove part height (H1) from the part to the deepest part position in the first groove part and the bottom part height (HB) from the grounding part of the pressure-resistant packaging container to the starting part of the bottom part. The first groove portion is formed at a position satisfying 0.2HB <H1 <HB. This relates to the bottom structure of the pressure-resistant packaging container.

  In the invention of claim 2, in addition to the first groove portion, the second groove portion recessed toward the inside of the leg portion extends along the circumferential direction of the pressure-resistant packaging container and extends over the length of the leg side surface portion. It is formed in the side part, The said 2nd groove part is the 1st groove part height (H1) from the grounding part of the said pressure-resistant packaging container to the deepest part position in the said 1st groove part, and the deepest part position in the said 1st groove part 0.4HB ≦ between the second groove height (H2) from the first groove to the deepest position in the second groove and the bottom height (HB) from the grounding portion of the pressure-resistant packaging container to the starting portion of the bottom. (H1 + H2) ≦ HB is satisfied, and the second groove portion is the leg side surface portion that rises from the height of the first groove portion of the first groove portion in the height direction of the bottom portion. The height (H1) of the groove and the height of the second groove (H2) According to the bottom structure of the pressure-resistant packaging container according to claim 1, which is formed in the spacing position in satisfying the 0.75H1 ≦ H2 ≦ 1.25H1 between the.

  According to a third aspect of the present invention, the deepest position of the first groove portion and the second groove portion is formed at a depth of 0.2 to 0.7 mm from the surface of the leg side surface portion. It relates to the bottom structure of a pressure-resistant packaging container.

  Invention of Claim 4 concerns on the bottom part structure of the pressure-resistant packaging container of Claim 2 or 3 in which the said 1st groove part and the said 2nd groove part are formed in the width | variety of 4-8 mm.

  The invention according to claim 5 is a pressure-resistant packaging container in which a thermoplastic polyester resin composition is integrally formed with a leg portion and a bottom portion for securing the self-supporting property of the container by stretch blow molding, and the bottom portion is a bottom hemispherical portion. The leg portion is formed of a curved pyramid trapezoidal shape including a leg side surface portion and a grounding portion continuous from the container body surface portion toward the bottom portion, and the leg portion is formed from the center of the bottom hemispherical portion in the pressure-resistant packaging. The central angle is equally divided in the circumferential direction of the container, and a plurality of radial portions are arranged to protrude radially in the grounding direction of the pressure-resistant packaging container, and the legs are arranged adjacent to each other via a trough. In the bottom structure of the pressure-resistant packaging container, the ratio of the maximum body diameter (D) of the pressure-resistant packaging container to the total height (HT) of the pressure-resistant packaging container is 0.30 ≦ (D / HT) ≦ 0.41 and Pressure-resistant packaging The ratio of the bottom height (HB) from the grounding portion of the pressure-resistant packaging container to the origin of the bottom with respect to the total height (HT) of 0.13 ≦ (HB / HT) ≦ 0.18 is satisfied, The present invention relates to a bottom structure of a pressure-resistant packaging container, wherein a concave portion that is concave toward the inner side is formed in a leg side surface portion of the leg portion.

  In the invention of claim 6, the ratio of the length (HR) of the longest portion in the height direction of the pressure-resistant packaging container to the bottom height (HB) of the concave portion is 0.65 ≦ (HR / HB) ≦ 0. .80, the ratio of the length (CR) of the longest portion in the circumferential direction of the pressure-resistant packaging container to the length (HR) of the longest portion in the height direction is 0.70 ≦ (CR / HR) ≦ 0.90, The depth of the deepest portion is 1.0 to 1.5 mm. The bottom structure of the pressure-resistant packaging container according to claim 5.

  The invention of claim 7 relates to the bottom structure of the pressure-resistant packaging container according to any one of claims 1 to 6, wherein the number of the leg portions is 4 to 7.

  The invention according to claim 8 relates to the bottom structure of the pressure-resistant packaging container according to any one of claims 1 to 7, wherein the pressure-resistant packaging container is a container for an internal volume of 300 to 600 mL.

  The bottom structure of the pressure-resistant packaging container according to the first aspect of the present invention is a pressure-resistant packaging container in which a thermoplastic polyester resin composition is integrally provided with a leg portion and a bottom portion for securing the self-supporting property of the container by stretch blow molding. The bottom portion is formed as a bottom hemispherical portion, and the leg portion is formed of a curved pyramid trapezoidal shape including a leg side surface portion and a grounding portion continuous from the container body surface portion toward the bottom portion, and the leg portion is the bottom portion. A central angle is equally divided from the center of the hemispherical portion in the circumferential direction of the pressure-resistant packaging container and spaced apart by a predetermined interval, and a plurality of radial protrusions are arranged in the grounding direction of the pressure-resistant packaging container. In the bottom structure of the pressure-resistant packaging container disposed adjacent to each other, the ratio of the maximum body diameter (D) of the pressure-resistant packaging container to the total height (HT) of the pressure-resistant packaging container is 0.30 ≦ (D / HT) ≦ 0 41, and the ratio of the bottom height (HB) from the grounding portion of the pressure-resistant packaging container to the origin of the bottom with respect to the total height (HT) of the pressure-resistant packaging container is 0.13 ≦ (HB / HT) ≦ 0. The first groove portion that is concave toward the inside of the leg portion is formed in the leg side surface portion along the circumferential direction of the pressure-resistant packaging container and over the length of the leg side surface portion, Between the first groove part height (H1) from the grounding part of the pressure-resistant packaging container to the deepest position in the first groove part and the bottom part height (HB) from the grounding part of the pressure-resistant packaging container to the starting part of the bottom part Since the first groove portion is formed at a position satisfying 0.2HB <H1 <HB from the grounding portion, wrinkles generated in the legs of the pressure-resistant packaging container are effectively suppressed as compared with the conventional case. can do.

  According to a second aspect of the present invention, in the first aspect, in addition to the first groove portion, the second groove portion that is recessed toward the inside of the leg portion extends along the circumferential direction of the pressure-resistant packaging container and the length of the leg side surface portion. The second groove portion is formed on the leg side surface portion over a period of time, and the first groove portion height (H1) from the ground contact portion of the pressure-resistant packaging container to the deepest portion position in the first groove portion, and the first groove portion. Between the 2nd groove part height (H2) from the deepest part position in a groove part to the deepest part position in the said 2nd groove part, and the bottom part height (HB) from the earthing | grounding part of the said pressure-resistant packaging container to the origin part of the said bottom part 0.4HB ≦ (H1 + H2) ≦ HB, and the second groove portion is the leg side surface portion that rises from the first groove height of the first groove portion in the height direction of the bottom portion. The first groove height (H1) and the second groove height Because it is formed at a position where the interval in satisfying the 0.75H1 ≦ H2 ≦ 1.25H1 between the serial vertical length (H2), it is possible to further improve the effect of suppressing wrinkles.

  According to a third aspect of the present invention, in the second aspect, the deepest position of the first groove portion and the second groove portion is formed at a depth of 0.2 to 0.7 mm from the surface of the leg side surface portion. In addition, the effect of suppressing wrinkles can be sufficiently obtained, and the releasability during molding is not impaired.

  The invention of claim 4 is the method according to claim 2 or 3, wherein the first groove part and the second groove part are formed to have a width of 4 to 8 mm. There is no loss of time releasability.

  The bottom structure of the pressure-resistant packaging container according to the invention of claim 5 is a pressure-resistant packaging container formed by integrally forming a leg portion and a bottom portion for securing the self-supporting property of the container by stretch blow molding of the thermoplastic polyester resin composition. The bottom portion is formed as a bottom hemispherical portion, and the leg portion is formed of a curved pyramid trapezoidal shape including a leg side surface portion and a grounding portion continuous from the container body surface portion toward the bottom portion, and the leg portion is the bottom portion. A central angle is equally divided from the center of the hemispherical portion in the circumferential direction of the pressure-resistant packaging container and spaced apart by a predetermined interval, and a plurality of radial protrusions are arranged in the grounding direction of the pressure-resistant packaging container. In the bottom structure of the pressure-resistant packaging container disposed adjacent to each other, the ratio of the maximum body diameter (D) of the pressure-resistant packaging container to the total height (HT) of the pressure-resistant packaging container is 0.30 ≦ (D / HT) ≦ 0 41, and the ratio of the bottom height (HB) from the grounding portion of the pressure-resistant packaging container to the origin of the bottom with respect to the total height (HT) of the pressure-resistant packaging container is 0.13 ≦ (HB / HT) ≦ 0. 18 is satisfied, and the concave portion that is concave toward the inner side is formed in the leg side surface portion of the leg portion, so that wrinkles generated in the leg portion of the pressure-resistant packaging container are effectively suppressed as compared with the conventional case. be able to.

  According to a sixth aspect of the present invention, in the fifth aspect, the concave portion has a ratio of the length (HR) of the longest portion in the height direction of the pressure-resistant packaging container to the bottom height (HB) of 0.65 ≦ (HR /HB)≦0.75, the ratio of the length (CR) of the longest portion in the circumferential direction of the pressure-resistant packaging container to the length (HR) of the longest portion in the height direction is 0.70 ≦ (CR / HR) Since ≦ 0.90 and the depth of the deepest part is 1.0 to 1.5 mm, the effect of suppressing wrinkles can be sufficiently obtained, and the releasability during molding is not impaired.

  A seventh aspect of the present invention is that, since the number of the leg portions is four to seven in the first to sixth aspects, sufficient durability can be obtained and molding is easy.

  The invention of claim 8 can be an alternative to the market standard in claims 1 to 7 because the pressure-resistant packaging container is a container for an internal volume of 300 to 600 mL.

It is a perspective view of the pressure-resistant packaging container which concerns on one Example of this invention. It is a top view of the bottom part of the pressure-resistant packaging container of FIG. It is a perspective view of the bottom part of the pressure-resistant packaging container in which the 1st groove part was formed in the leg part. It is a perspective view of the bottom part of the pressure-resistant packaging container in which the 1st groove part and the 2nd groove part were formed in the leg part. It is a schematic side view of the bottom part of FIG. It is a perspective view of the bottom part of the pressure-resistant packaging container in which the recessed part was formed in the leg part. It is a perspective view of the bottom part of the pressure-resistant packaging container in which the three recessed groove parts were formed in the leg part. It is a perspective view of the conventional pressure-resistant packaging container. It is a perspective view of the bottom part of the conventional pressure-resistant packaging container. It is a schematic diagram showing the state where the internal pressure was applied to the grounding part of a pressure-resistant packaging container. It is a top view of the bottom part of the pressure-resistant packaging container which wrinkles generate | occur | produced. It is a perspective view of the bottom part of the conventional pressure-resistant packaging container in which the groove part was formed in the lower end part of a leg side part.

  FIG. 1 shows a pressure-resistant packaging container 10 according to an embodiment of the present invention, which is formed by integrally forming a bottom portion 20 and a leg portion 30 by stretch blow molding a thermoplastic polyester resin composition. As the thermoplastic polyester resin composition constituting the container 10, a material constituting a known PET bottle such as polyethylene terephthalate is preferably used. In addition, the code | symbol 11 in a figure is a container trunk | drum, 12 is a container opening | mouth part.

  As shown in FIGS. 1 and 2, the bottom portion 20 is formed as a bottom hemispherical portion 25 and includes a leg portion 30 described later. In the figure, reference numeral 21 denotes a starting point portion that becomes a boundary between the container 10 and the container body 11.

  The leg portion 30 is provided on the bottom portion 20 in order to ensure the self-supporting property of the container 10, and is formed from a curved pyramid trapezoidal shape including a leg side surface portion 31 and a ground contact portion 32 that continue from the container trunk surface portion 11 </ b> A toward the bottom portion 20. Become. As shown in FIGS. 2 and 3, the leg portions 30 are equally divided from the center of the bottom hemispherical portion 25 in the circumferential direction of the pressure-resistant packaging container 10 in the circumferential direction and separated radially by a predetermined interval. A plurality of protrusions 10 are arranged in the grounding direction. The plurality of leg portions 30 are arranged such that the leg portions are adjacent to each other via a valley portion 33. Each leg part 30 of an Example is what is called a petaloid shape. The valley portion 33 also serves as the bottom hemispherical portion 25 of the bottom portion 20.

  The number of the leg portions 30 is not particularly limited as long as the self-supporting property of the container 10 can be ensured, but it is 4 to 7 in terms of durability, ease of molding, and the like. preferable. When the number of the leg portions 30 is less than 4, there is a problem that the leg side surface portion of one leg portion 30 becomes too large and sufficient durability cannot be obtained. When there are more than seven leg portions 30, the leg portions 30 become extremely small, and molding becomes difficult. The number of the leg portions 30 in the embodiment is five.

  Next, a suitable size of the pressure-resistant packaging container 10 is a general size in which soft drinks (carbonated drinks) in which carbon dioxide gas is dissolved are filled as contents and distributed to the market. That is, as understood from the commercial containers A to L shown in Table 1, the ratio of the maximum trunk diameter D to the total height HT from the container mouth portion 12 to the grounding portion 32 of the container 10 is 0.30 ≦ (D / HT) ≦ 0.41 and the ratio of the bottom height HB from the ground contact portion 32 to the starting portion 21 of the bottom 20 with respect to the total height HT satisfies 0.13 ≦ (HB / HT) ≦ 0.18. In particular, the pressure-resistant packaging container 10 is preferably a container for an internal volume of 300 to 600 mL.

  When (D / HT) is smaller than 0.30, the overall height HT becomes too high, causing a problem in the market distribution such that the container 10 deviates from the standard of the conventional product and does not enter the display shelf of a store or the like. When (D / HT) is larger than 0.41, there arises a problem in the market distribution such that the maximum trunk diameter D becomes too large and deviates from the standard of the conventional product and cannot enter the display shelf of a store or the like. When (HB / HT) is smaller than 0.13, the height of the bottom portion 20 becomes too low, and it becomes difficult to ensure the self-supporting property by the leg portion 30, and the effect of dispersing the internal pressure by the contents is lowered, resulting in durability. Problems arise. When (HB / HT) is larger than 0.18, the height of the bottom portion 20 becomes too high, causing a problem in releasability during molding. Moreover, in the container 10 of this invention, the capacity | capacitance is 300-600 mL. This capacity is a widely used container in the market and can be an alternative to market standards.

  The pressure-resistant packaging container 10 of the present invention has a first groove part 40 that is recessed toward the inside of the leg part 30 in order to suppress wrinkles generated in the leg part 30 as can be understood from the examples described later. Along the circumferential direction, the leg side surface portion 31 is formed over the length of the leg side surface portion 31 (see FIG. 3). The first groove portion 40 is assumed to be concave toward the inner side of the leg portion 30, thereby acting as a buffer structure for dispersing the tensile force due to the internal pressure of the contents concentrated on the ground contact portion 32 of the leg portion 30. Is done.

  Moreover, in order to suppress wrinkle generation more effectively, in addition to the first groove portion 40, a second groove portion 50 that is recessed toward the inner side of the leg portion 30 extends along the circumferential direction of the container and It forms in the leg side surface part 31 over the length (refer FIG. 4). The second groove portion 50 acts as a buffer structure in the same manner as the first groove portion 40, thereby further dispersing the tensile force due to the internal pressure of the contents concentrated on the ground contact portion 32 of the leg portion 30 together with the first groove portion 40. It is presumed that the suppression effect is improved.

  As shown in FIG. 5, the first groove portion 40 has a first groove portion height from the grounding portion 32 of the pressure-resistant packaging container 10 to the deepest portion position 41 in the first groove portion 40 as a condition for effectively suppressing the generation of wrinkles. It is formed at a position satisfying 0.2HB <H1 <HB from the grounding portion 32 between H1 and the bottom height HB from the grounding portion 32 of the pressure-resistant packaging container 10 to the starting portion 21 of the bottom portion 20. When 1st groove part height H1 is 0.2 HB or less, the inhibitory effect of the wrinkle which generate | occur | produces in the leg part 30 cannot fully be acquired. When the 1st groove part height H1 is more than HB, it becomes impossible to form the 1st groove part 40 in the leg part 30, and a wrinkle suppression effect cannot be acquired.

  As shown in FIG. 5, the second groove 50 has a first groove height H1 from the grounding portion 32 of the pressure-resistant packaging container 10 to the deepest position 41 in the first groove 40 as a condition for further improving the wrinkle suppression effect. The second groove height H2 from the deepest position 41 in the first groove 40 to the deepest position 51 in the second groove 50, and the bottom height from the grounding portion 32 of the pressure-resistant packaging container 10 to the starting point 21 of the bottom 20 The leg side surface portion 31 that satisfies 0.4HB ≦ (H1 + H2) ≦ HB with respect to the height HB and that rises in the height direction of the bottom portion 20 from the first groove height H1 of the first groove portion 40. Thus, the gap is formed at a position satisfying 0.75H1 ≦ H2 ≦ 1.25H1 between the first groove height H1 and the second groove height H2.

  When the sum (H1 + H2) of the first groove height H1 and the second groove height H2 is smaller than 0.4HB, the effect of suppressing wrinkles generated in the legs 30 cannot be sufficiently obtained. When the sum (H1 + H2) of the first groove height H1 and the second groove height H2 is larger than HB, it becomes impossible to form the second groove 50 in the leg portion 30, and a sufficient wrinkle suppressing effect is obtained. I can't. When 2nd groove part height H2 is smaller than 0.75H1, the space | interval of the 1st groove part 40 and the 2nd groove part 50 becomes too narrow, and cannot suppress the wrinkle suppression effect. When 2nd groove part height H2 is larger than 1.25H1, the space | interval of the 1st groove part 40 and the 2nd groove part 50 becomes too wide, and cannot suppress the wrinkle suppression effect.

  Moreover, in the 1st groove part 40 and the 2nd groove part 50, the deepest part 41 and 51 position is 0.2-0.7 mm from the surface of the leg side part 31 from a viewpoint of the suppression effect of a wrinkle, and the mold release property at the time of shaping | molding. It is formed to a depth. When the depth of the deepest portions 41 and 51 is shallower than 0.2 mm, the groove portions 40 and 50 are too shallow to sufficiently obtain a wrinkle suppressing effect. When the depth of the deepest portions 41 and 51 is deeper than 0.7 mm, the difference from the surface of the leg side surface portion 31 becomes too large, which causes a problem in releasability during molding.

  Furthermore, the 1st groove part 40 and the 2nd groove part 50 are formed in the width | variety of 4-8 mm from a viewpoint of the suppression effect of a wrinkle, and the mold release property at the time of shaping | molding. When the widths of the first groove portion 40 and the second groove portion 50 are narrower than 4 mm, the widths of the groove portions 40 and 50 are too narrow, causing a problem in releasability during molding. When the widths of the first groove part 40 and the second groove part 50 are wider than 8 mm, the widths of the groove parts 40 and 50 are too wide to obtain a sufficient wrinkle suppressing effect.

  Moreover, in the pressure-resistant packaging container 10 of this invention, as shown in FIG. 6, it is also possible to suppress generation | occurrence | production of a wrinkle by forming the recessed part 60 which becomes concave to the inner side in the leg side part 31 of the leg part 30. It is. It is presumed that the concave portion 60 also acts as a buffer structure like the first groove portion 40. The ratio of the length HR of the longest portion in the height direction of the pressure-resistant packaging container 10 to the bottom height HB is 0.65 ≦ (HR / HB) ≦ as a condition for the concave portion 60 to effectively suppress the generation of wrinkles. 0.80, the ratio of the longest length CR in the circumferential direction of the pressure-resistant packaging container 10 to the longest length HR in the height direction is 0.70 ≦ (CR / HR) ≦ 0.90, the deepest portion It is formed so that the depth of 61 is 1.0 to 1.5 mm. The shape of the recess 60 is not particularly limited, but is a teardrop shape in the illustrated example.

  When (HR / HB) is smaller than 0.65, the length of the recess 60 in the height direction is too short, and the effect of suppressing wrinkles cannot be sufficiently obtained. When (HR / HB) is larger than 0.75, it is difficult to form the recess 60 in the leg side surface 31 of the leg 30 because the length of the recess 60 is too long. When (CR / HR) is smaller than 0.70, the length in the circumferential direction is too short to sufficiently obtain the effect of suppressing wrinkles. When (CR / HR) is larger than 0.90, the circumferential length of the concave portion 60 is too long, and it is difficult to form the concave portion 60 in the leg side surface portion 31 of the leg portion 30. When the depth of the deepest part 61 is shallower than 1.0 mm, the recessed part 60 is too shallow and cannot fully obtain the wrinkle suppression effect. When the depth of the deepest portion 61 is deeper than 1.5 mm, the difference from the surface of the leg side surface portion 31 becomes too large, which causes a problem in releasability during molding.

  Furthermore, in the pressure-resistant packaging container 10 of the present invention, as shown in FIG. 7, the leg side surface portion 31 of the leg portion 30 is recessed toward the inner side and has three groove-like groove portions (bottom grooves) along the circumferential direction of the container. The concave groove portion 70, the middle concave groove portion 71, and the upper concave groove portion 72) may be formed in the leg side surface portion 31. It is presumed that the concave groove portions 70, 71, 72 also act as a buffer structure like the first groove portion 40 and the second groove portion 50. Each of the concave groove portions 70, 71, 72 has a maximum portion width of 4 to 8 mm and a depth of the deepest portion 75, 76, 77 position from the surface of the leg side surface portion 31 as a condition for effectively suppressing the generation of wrinkles. The distance between the lower groove portion 70 and the upper groove portion 72 is 0.2 to 0.7 mm, and is formed so as to satisfy a ratio of 0.55 to 0.75 with respect to the bottom height HB. Although the shape of each groove part 70,71,72 is not specifically limited, In the example of illustration, it is elliptical shape.

  When the width of the maximum part of each groove part 70, 71, 72 is narrower than 4 mm, the width of each groove part 70, 71, 72 is too narrow, and the problem arises in the mold release property at the time of shaping | molding. When the width of the maximum part of each groove part 70,71,72 is wider than 8 mm, the width | variety of each groove part 70,71,72 is too wide, and cannot fully obtain the wrinkle suppression effect. When the depth of the deepest portion 75, 76, 77 is shallower than 0.2 mm, the concave groove portions 70, 71, 72 are too shallow to sufficiently obtain the wrinkle suppressing effect. When the depth of the deepest portion 75, 76, 77 is deeper than 0.7 mm, the difference from the surface of the leg side surface portion 31 becomes too large, which causes a problem in releasability during molding. When the ratio of the distance between the lower groove portion 70 and the upper groove portion 72 with respect to the bottom height HB is smaller than 0.65, the space between the groove portions 70, 71, 72 becomes too narrow and a sufficient wrinkle suppressing effect is obtained. I can't. When the ratio of the interval between the lower groove portion 70 and the upper groove portion 72 with respect to the bottom height HB is larger than 0.75, the interval between the groove portions 70, 71, 72 is too wide and the inside of the leg side surface portion 31 of the leg portion 30. It is difficult to form the concave groove portions 70, 71, and 72.

  The inventors have made blow-molding of conventionally known polyethylene terephthalate to vary the structure of the bottom having legs arranged in a petaloid shape, and the pressure-resistant packaging for 500 mL with a molded container weight of 24 g. A container was prototyped. In the pressure-resistant packaging containers of the following prototype examples 1 to 6, the total height HT is 220 mm, the maximum trunk diameter D is 69 mm, and the bottom height HB is 29 mm.

  As shown in FIG. 9, the pressure-resistant packaging container of Prototype Example 1 has a conventional bottom structure in which the leg side surface 131 of the leg 130 is formed to be substantially smooth.

  As shown in FIG. 12, the pressure-resistant packaging container of Prototype Example 2 has a conventional bottom structure in which a groove part 140 is formed at the lower end part of the leg side part 131 of the leg part 130. In Prototype Example 2, the groove part 140 has a width of 4 mm, a depth of 0.7 mm, and a height from the grounding part 132 of 4.8 mm.

  As shown in FIG. 3, the pressure-resistant packaging container of Prototype Example 3 has a bottom structure in which a first groove portion 40 is formed in the leg side surface portion 31 of the leg portion 30. In Prototype Example 3, the first groove portion 40 has a width of 4 mm, a depth of 0.21 mm, and a height from the ground contact portion 32 (first groove portion height H1) is 12.5 mm.

  The pressure-resistant packaging container of Prototype Example 4 has a bottom structure in which a first groove portion 40 and a second groove portion 50 are formed in the leg side surface portion 31 of the leg portion 30 as shown in FIG. In Prototype Example 4, the first groove part 40 has a width of 4 mm, a depth of 0.25 mm, a height from the grounding part 32 (first groove part height H1) of 8.5 mm, and the second groove part 50 is The width is 4 mm, the depth is 0.25 mm, and the height from the grounding portion 32 is 16.5 mm (the second groove height H2 is 8 mm).

  As shown in FIG. 6, the pressure-resistant packaging container of Prototype Example 5 has a bottom structure in which a recess 60 is formed in the leg side surface portion 31 of the leg portion 30. In Prototype Example 5, the length of the longest portion in the height direction is 22 mm, the length of the longest portion in the circumferential direction is 19 mm, and the depth is 1.3 mm.

  As shown in FIG. 7, the pressure-resistant packaging container of Prototype Example 6 has a bottom structure in which three concave groove portions 70, 71, 72 are formed in the leg side surface portion 31 of the leg portion 30. In Prototype Example 6, the lower concave groove portion 70 has a width of 4 mm, a depth of 0.45 mm, and a height from the grounding portion 32 of 6.5 mm, and the middle concave groove portion 71 has a width of 6 mm and a depth of 0. 0.5 mm, the height from the grounding portion 32 is 14 mm, the upper concave groove portion 72 has a width of 8 mm, a depth of 0.5 mm, and a height from the grounding portion 32 of 23 mm (the distance from the lower concave groove portion 70 is 16.5 mm).

  Next, five pressure-resistant packaging containers of Prototype Examples 1 to 6 were prepared, and 8.25 g of citric acid (manufactured by Tokai Pharmaceutical Co., Ltd., purity 99.5%) was added to each container. Pure water was filled to the taste line of the container, 10.56 g of sodium bicarbonate (manufactured by Tokai Pharmaceutical Co., Ltd., third type pharmaceutical) was added, the lid was closed, and the reaction was completed by shaking well. The gas volume of the contents filled in each container is 5.0, which is higher than that of a normal carbonated beverage (2-3.5).

Each container thus obtained is stored in an upright condition at a constant temperature room of 22 ° C., and the presence or absence of wrinkles at the bottom of each container is observed visually and touched with a finger at regular intervals. Evaluation was made according to the following criteria. Table 2 shows the evaluation results of each container.
○: No wrinkle (no wrinkle is confirmed even when touched with eyes or fingers).
Δ: Wrinkle sign (no wrinkles are visually confirmed, but wrinkles are confirmed when touched with a finger).
X: wrinkles (wrinkles are confirmed visually).

  In Prototype Example 1 (conventional product), the container 1a showed wrinkle signs on the second day and was visually confirmed on the seventh day. The container 1b and the container 1c showed wrinkle signs on the first day, and wrinkles were visually confirmed on the fourth day. The container 1d showed wrinkle signs on the second day, but no wrinkle was visually confirmed even after 14 days. The container 1e showed wrinkle signs on the second day and was visually confirmed on the tenth day.

  In Prototype Example 2 (conventional product), the container 2a showed wrinkle signs on the 4th day, but no wrinkle was visually confirmed even after 14 days. In the containers 2b to 2d, wrinkle signs appeared on the second day, and wrinkles were visually confirmed on the tenth day. The container 2e showed wrinkle signs on the first day and was visually confirmed on the fourth day.

  In Prototype Example 3, the container 3a and the container 3c showed wrinkle signs on the 4th day and were visually confirmed on the 10th day. In the container 3b and the container 3e, generation of wrinkles was not confirmed at all even after 14 days. The container 3d showed wrinkle signs on the 7th day, but no wrinkle was visually confirmed even after 14 days.

  In Prototype Example 4, the generation of wrinkles was not confirmed at all for the containers 4a to 4e even after 14 days.

  In Prototype Example 5, the container 5a showed wrinkle signs on the second day and was visually confirmed on the tenth day. The container 5b showed wrinkle signs on the 10th day, but no wrinkle was visually confirmed even after 14 days. In the containers 5c to 5e, wrinkles were not observed at all even after 14 days.

  In Prototype Example 6, the container 6a showed wrinkle signs on the 4th day, but no wrinkle was visually confirmed even after 14 days. In the container 6b and the container 6e, generation of wrinkles was not confirmed at all even after 14 days. The container 6c showed wrinkle signs on the 4th day and was visually confirmed on the 10th day. The container 6d showed wrinkle signs on the second day and was visually confirmed on the tenth day.

 As understood from the evaluation results in Table 2, in the prototype 1 (conventional product) and the prototype 2 (conventional product), signs of wrinkles appear from an early stage, and finally can be visually confirmed in most containers. Wrinkles occurred. In particular, the prototype 2 has an effect of slightly delaying the generation of wrinkles that can be visually confirmed as compared with the prototype 1, but it is clear that the effect of suppressing the generation of wrinkles is not sufficient. It was.

  On the other hand, in Prototype Example 3 having the first groove portion 40 and Prototype Example 6 having the three recesses 70, 71, 72, wrinkles did not occur at all in the two containers (3b, 3e, 6b, 6e). . On the other hand, even if wrinkles occur, the wrinkles are rarely visible enough to be visually confirmed when stored for a long time, and the wrinkle signs appear to be slower than in Prototype Example 2 (conventional product). . Moreover, in the prototype 5 which has the recessed part 60, wrinkles did not generate | occur | produce at all by three containers (5c-5e), and generation | occurrence | production of wrinkles was suppressed more effectively than the prototypes 3 and 6. In these prototype examples 3, 5, and 6, it was found that when a normal carbonated beverage (gas volume 2 to 3.5) is filled and distributed in the market, the effect of suppressing wrinkles can be sufficiently obtained.

  In particular, in Prototype Example 4 having the first groove portion 40 and the second groove portion 50, wrinkles are not generated at all in all the containers (4a to 3e), and the wrinkle suppressing effect is further superior to Prototype Examples 3, 5, and 6. It became clear that

DESCRIPTION OF SYMBOLS 10 Pressure-resistant packaging container 20 Bottom part 30 Leg part 31 Leg side part 32 Grounding part 40 1st groove part 50 2nd groove part D Maximum trunk | drum diameter of a pressure-resistant packaging container HB Bottom height of a pressure-resistant packaging container HT Overall height of a pressure-resistant packaging container H1 1st groove part Height H2 Second groove height

Claims (8)

In the pressure-resistant packaging container formed by integrally forming a leg portion and a bottom portion for securing the self-supporting property of the container by stretch blow molding the thermoplastic polyester resin composition, the bottom portion is formed as a bottom hemispherical portion,
The leg portion has a curved pyramid trapezoidal shape including a leg side surface portion and a grounding portion continuous from the container body surface portion toward the bottom portion, and the leg portion is a circle of the pressure-resistant packaging container from the center of the bottom hemispherical portion. The central angle is equally divided in the circumferential direction and spaced apart by a predetermined interval, and a plurality of radial projections are arranged in the grounding direction of the pressure-resistant packaging container,
In the bottom structure of the pressure-resistant packaging container in which the legs are arranged adjacent to each other via a valley,
The ratio of the maximum body diameter (D) of the pressure-resistant packaging container to the total height (HT) of the pressure-resistant packaging container is 0.30 ≦ (D / HT) ≦ 0.41, and the total height (HT) of the pressure-resistant packaging container The ratio of the bottom height (HB) from the grounding portion of the pressure-resistant packaging container to the starting point of the bottom satisfies 0.13 ≦ (HB / HT) ≦ 0.18,
A first groove part that is recessed toward the inside of the leg part is formed in the leg side part over the length of the leg side part along the circumferential direction of the pressure-resistant packaging container,
The first groove part height (H1) from the grounding part of the pressure-resistant packaging container to the deepest position in the first groove part and the bottom height (HB) from the grounding part of the pressure-resistant packaging container to the starting point of the bottom part. The bottom structure of the pressure-resistant packaging container, wherein the first groove is formed at a position satisfying 0.2HB <H1 <HB from the grounding portion. In addition to the first groove portion, a second groove portion that is recessed toward the inside of the leg portion is formed in the leg side surface portion along the circumferential direction of the pressure-resistant packaging container and over the length of the leg side surface portion. ,
The second groove part includes a first groove part height (H1) from a grounding part of the pressure-resistant packaging container to a deepest part position in the first groove part, and a deepest part in the second groove part from a deepest part position in the first groove part. 0.4HB ≦ (H1 + H2) ≦ HB between the second groove height (H2) to the position and the bottom height (HB) from the grounding portion of the pressure-resistant packaging container to the starting point of the bottom The filling,
The second groove portion is the leg side surface portion that rises in the height direction of the bottom portion from the height of the first groove portion of the first groove portion, and the first groove portion height (H1) and the second groove portion height. The bottom structure of the pressure-resistant packaging container according to claim 1, wherein the bottom portion structure is formed at a position satisfying the relationship of 0.75H1 ≦ H2 ≦ 1.25H1 with respect to the vertical length (H2).   The bottom part structure of the pressure-resistant packaging container according to claim 2, wherein the deepest position of the first groove part and the second groove part is formed at a depth of 0.2 to 0.7 mm from the surface of the leg side part.   The bottom part structure of the pressure-resistant packaging container according to claim 2 or 3, wherein the first groove part and the second groove part are formed to have a width of 4 to 8 mm. In the pressure-resistant packaging container formed by integrally forming a leg and a bottom for securing the self-supporting property of the container by stretch blow molding the thermoplastic polyester resin composition, the bottom is formed as a bottom hemispherical part,
The leg portion has a curved pyramid trapezoidal shape including a leg side surface portion and a grounding portion continuous from the container body surface portion toward the bottom portion, and the leg portion is a circle of the pressure-resistant packaging container from the center of the bottom hemispherical portion. The central angle is equally divided in the circumferential direction and spaced apart by a predetermined interval, and a plurality of radial projections are arranged in the grounding direction of the pressure-resistant packaging container,
In the bottom structure of the pressure-resistant packaging container in which the legs are arranged adjacent to each other via a valley,
The ratio of the maximum body diameter (D) of the pressure-resistant packaging container to the total height (HT) of the pressure-resistant packaging container is 0.30 ≦ (D / HT) ≦ 0.41, and the total height (HT) of the pressure-resistant packaging container The ratio of the bottom height (HB) from the grounding portion of the pressure-resistant packaging container to the starting point of the bottom satisfies 0.13 ≦ (HB / HT) ≦ 0.18,
A bottom structure of a pressure-resistant packaging container, wherein a concave portion that is concave toward the inside is formed in a leg side surface portion of the leg portion.   In the concave portion, the ratio of the length (HR) of the longest portion in the height direction of the pressure-resistant packaging container to the bottom height (HB) is 0.65 ≦ (HR / HB) ≦ 0.80, in the height direction. The ratio of the length (CR) of the longest portion in the circumferential direction of the pressure-resistant packaging container to the length (HR) of the longest portion is 0.70 ≦ (CR / HR) ≦ 0.90, and the depth of the deepest portion is 1. The bottom structure of the pressure-resistant packaging container according to claim 5, which is 0.0 to 1.5 mm.   The bottom structure of a pressure-resistant packaging container according to any one of claims 1 to 6, wherein the number of the leg portions is 4 to 7.   The bottom structure of a pressure-resistant packaging container according to any one of claims 1 to 7, wherein the pressure-resistant packaging container is a container for an internal volume of 300 to 600 mL.

Images