JP7110544B2 - synthetic resin bottle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a synthetic resin bottle, and more particularly, to a synthetic resin bottle having a vacuum absorption panel on its body and having a label-attached body of a nearly circular cylinder.

Synthetic resin bottles for beverages made of synthetic resin such as PET (polyethylene terephthalate) have various advantages such as low cost and light weight. For non-carbonated beverages, the beverage is sterilized by heating at a high temperature, filled into a heat-resistant bottle at a high temperature, and sealed. Aseptic filling is performed in which beverages are filled into bottles at normal temperature (about 30° C.) under aseptic conditions and sealed. In addition, the above-mentioned aseptic filled bottle (aseptic bottle) may experience a decrease in internal pressure (decompression) due to volume change over time in an unopened state, which may cause deformation. is equipped with vacuum absorbing panels.
On the other hand, in the synthetic resin bottle described in Patent Document 1, the bottom plate is provided with a reduced-pressure absorbing portion consisting of a mortar-shaped concave portion in which a spiral concave groove is formed. It is provided with reinforcements consisting of shaped grooves.
In addition, in the plastic bottle described in Patent Document 2, the cross section of the bottle body is octagonal, arcuate wall surfaces are formed at each corner, and pressure reduction absorption consisting of an inclined wall and a flat wall is formed between the arcuate wall surfaces. The plastic bottle is an octahedral bottle with surfaces arranged and capable of being filled under heat, and is provided with a reduced-pressure absorption surface in which the column angle formed by inclined walls connected to both sides of a circular arc wall surface is in the range of 60° to 115°.

JP 2015-131664 A Japanese Patent Application Laid-Open No. 2001-206331

A synthetic resin bottle disclosed in Patent Document 1, in which a vacuum absorbing portion is provided on the bottom plate and a reinforcing portion composed of a plurality of circumferential grooves (beads) arranged in parallel in the height direction is provided in the body, or in Patent Document 2. In the disclosed plastic bottle in which a vacuum absorption surface (vacuum absorption panel) is arranged on the body of the bottle, when a label, especially a shrink label made of a heat-shrinkable film, is attached to the body, the bead and the vacuum absorption panel are made of synthetic resin. It has a distinctive appearance in the bottle made from it. Depending on the type of beverage to be filled and sealed, the appearance of such a synthetic resin bottle may not be suitable as a container. For example, like glass or metal bottles, it is sometimes preferred that the outer appearance of the body of a synthetic resin bottle is a perfectly circular cylinder. However, in synthetic resin bottles, it has been difficult to achieve both the above-described reduced pressure absorption performance and the outer appearance of the barrel with the label attached to it to exhibit a perfectly circular cylindrical shape.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a synthetic resin bottle that has reduced pressure absorbing performance for absorbing a drop in internal pressure, and that has a label-attached body portion that exhibits a nearly perfect circular cylindrical appearance.

The present invention provides a synthetic resin bottle for aseptic filling having a cylindrical body, in which eight vacuum absorption panels are arranged at regular intervals on the body, and the panels are arranged between the vacuum absorption panels. The reduced pressure absorption panel absorbs the reduced pressure after filling the liquid at room temperature and sealing the synthetic resin bottle, and the cross section of the body is The arc-shaped wall surface of the pillar constitutes a part of one virtual perfect circle, and the total circumference of the arc-shaped wall surface of the pillar is 20 to 50% of the total circumference of the perfect circle. In the lateral cross section of the body, the end of the vacuum absorbing panel connected to the circumferential edge of the column is curved with a radius of curvature of 5 mm or more.

The present invention also provides a synthetic resin bottle for aseptic filling, having a cylindrical body, comprising eight vacuum absorption panels arranged at regular intervals on the body and between the vacuum absorption panels. and an arcuate wall pillar disposed thereon, the vacuum absorbing panel absorbing vacuum after filling with room temperature liquid and sealing of the synthetic resin bottle, and extending across the body. The arc-shaped wall surface of the column in the plane constitutes a part of one virtual perfect circle, and the radial line passing through the circumferential center of the column and the diameter passing through the circumferential edge of the column The angle formed by the direction line is 20 to 50% of the angle formed by a radial line passing through the circumferential center of the column and a radial line passing through the circumferential center of the vacuum absorbing panel adjacent to the column. Another feature is that, in the cross section of the trunk portion, the end portion of the vacuum absorption panel connected to the circumferential edge of the column portion is a curve with a radius of curvature of 5 mm or more.

In the synthetic resin bottle of the present invention, the number of pressure reduction absorption panels constituting the body and the ratio of the area occupied by the column of the body in the cross section, the pressure reduction absorption of the internal pressure drop and the body with the label attached. It stipulates the range in which the external appearance of the part can exhibit a cylinder close to a perfect circle.

According to the synthetic resin bottle of the present invention, it is possible to obtain a synthetic resin bottle that has the ability to absorb pressure drop inside the bottle, and that the label-attached barrel has a nearly perfect circular cylindrical appearance. can.

1 is a front view of a synthetic resin bottle according to a first embodiment of the present invention; FIG. FIG. 2 is a cross-sectional view schematically showing an outline along the SS line of FIG. 1 by contour lines; Figure 3 is an enlarged cross-sectional view of a portion of Figure 2; FIG. 2 is a front view showing a state in which a shrink label is attached to the synthetic resin bottle of FIG. 1; FIG. 5 is an enlarged cross-sectional view schematically showing a part of the outer shape along the SS line of FIG. 4 by a contour line; 1. It is an enlarged cross-sectional view schematically showing a part of the outline before and after heating when the synthetic resin bottle of FIG. 1 is filled with a beverage. 7 is a graph showing the relationship between the radius of curvature of the concave portion of the vacuum absorption panel of the synthetic resin bottle filled with the beverage shown in FIG. 6 and the swelling amount in the heated state. Fig. 2 is a front view of a synthetic resin bottle according to a second embodiment of the present invention;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Basic structure of synthetic resin bottle]
FIG. 1 shows a front view of a synthetic resin bottle 1 according to a first embodiment of the present invention, and FIG. 2 schematically shows a cross-sectional shape taken along line SS of FIG. FIG. 3 shows an enlarged part of FIG. The synthetic resin bottle 1 is made of a synthetic resin such as polyethylene terephthalate (PET) and is used to contain and store non-carbonated beverages such as coffee and tea. is a bottle. As shown in FIG. 1, the synthetic resin bottle 1 has a heel portion 2, a cylindrical body portion 3, and a tapered (substantially conical) shape that tapers upward from the bottom to the top. The bottle is provided with a shoulder portion 4 and a neck portion 5 with a small diameter, and can stand on its own while the heel portion 2 is placed on a flat surface (eg, the top surface or floor surface of a desk or table). The end of the neck 5 is an opening that serves as a drinking spout. A male threaded portion 6 is provided on the outer periphery of the opening, and a screw cap 7 having a female threaded portion (not shown) is screwed into and sealed.

[Structure of trunk]
As shown in FIGS. 1 and 2, on the body portion 3 of the synthetic resin bottle 1, eight vacuum absorption panels 8 having arcuate top and bottom are arranged at regular intervals. A portion 9 is provided and the vacuum absorbing panel 8 has a recess 8a. As shown in FIGS. 2 and 3, the pillar portion 9 is formed of an arc-shaped wall surface 9a, and the arc-shaped wall surface 9a of all the pillar portions 9 in the cross section of the body portion 3 is a part of one virtual perfect circle 10. are configured respectively. On the other hand, the wall surface of the decompression absorption panel 8 is concave or planar, and does not overlap the perfect circle 10 virtually formed by connecting the arc-shaped wall surfaces 9a of all the pillars 9 . In the present invention, in the cross section of the body 3 (for example, the cross section along the SS line), the total circumference of the arc-shaped wall surface 9a of each column 9 (referred to as "total circumference A of all columns") is , and 20 to 50% of the total circumference of a perfect circle 10 (referred to as “perfect circle total circumference B”) formed virtually by connecting the arc-shaped wall surfaces 9a of all the pillars 9. As shown in FIG. In the illustrated specific example, the total circumference A of all pillars is 27% of the total circumference B of the perfect circle.

In the body portion 3 of the synthetic resin bottle 1, when all the vacuum absorption panels 8 have the same circumferential length and all the pillars 9 have the same shape and have the same circumferential length, the above-mentioned The ratio A/B of the total circumference A of all the pillars to the total circumference B of the perfect circle can be obtained as follows. That is, as shown in FIG. 3, in the cross section, a radial line L1 passing through the circumferential center 8b of the decompression absorption panel 8 and a radial line L2 passing through the circumferential center 9c of the column portion 9 adjacent thereto form. The ratio X/Y of the angle X formed by the radial line L2 and the radial line L3 passing through the circumferential edge 9b of the column portion 9 (vacuum absorption panel 8) to the angle Y is the ratio X/Y of the length A described above. /B. The circumferential edge 9b of the column 9 is a point where the curvature of the arc-shaped wall surface 9a changes, and is a boundary point between a portion overlapping the virtual perfect circle 10 and a portion not overlapping. Since the number of vacuum absorbing panels 8 and pillars 9 in this embodiment is eight, the angle Y is 360°/16=22.5°.

In the present invention, the technical significance of setting the total circumference A of all pillars to 20 to 50% of the total circumference B of the perfect circle as described above will be described.
In the conventional general synthetic resin bottle 1, the total circumference A of all the pillars in the cross section of the body 3 is 10% or less of the total circumference B of the perfect circle. In other words, the proportion of the panel 8 occupied by the reduced pressure absorption panel 8 is about 90% or more, and the deformation of the container 1 can be kept small by sufficiently absorbing the reduced pressure. However, since most of the body 3 is composed of the decompression absorption panel 8 whose wall surface is concave or flat rather than arc-shaped, the cross-sectional shape is substantially polygonal, and the body with the shrink label attached The appearance of 3 presents a substantially polygonal rectangular tube.

On the other hand, in the synthetic resin bottle of the present invention, the body 3 (see FIG. 4) attached with the shrink label has the appearance of a cylinder close to a perfect circle 10 while maintaining the vacuum absorption performance. We derive design conditions that exhibit First, the decompression over time in the unopened state of the synthetic resin bottle 1 filled with a beverage by aseptic filling is mainly due to a decrease in the volume of oxygen dissolved in the beverage in the head space of the neck 5, and a reduction in the volume of oxygen dissolved in the beverage. This is due to a decrease in the volume of the beverage contained in the bottle 1 due to a small amount of moisture permeating through the body 3 of the beverage. On the other hand, depressurization of synthetic resin bottles filled with beverages by hot filling causes the temperature of the beverage filled and sealed at high temperature and the gas in the headspace to cool to normal temperature in addition to the volume reduction in aseptic filling described above. It is also caused by volume reduction due to For this reason, the necessary amount of pressure reduction absorption in the synthetic resin bottle (aseptic bottle) 1 for aseptic filling is smaller than that in the synthetic resin bottle (heat-resistant bottle) for hot filling. For example, an aseptic bottle with an internal volume of about 400 ml (height: 162 mm, barrel diameter: 66 mm, barrel length: 103 mm, caliber: 38 mm) is about 7 ml per year. In consideration of such a difference in volume reduction, in order to secure the size of the decompression absorption panel 8 that absorbs the decompression and does not cause excessive deformation, the decompression absorption panel 8 must be 50% of the entire wall surface of the torso 3. % or more. Therefore, in the present invention, the total circumferential length A of the column portion 9 in the cross section of the body portion 3 is set to 50% or less of the total circumferential length B of the perfect circle 10 to secure the size of the pressure reduction absorption panel 8, Enables vacuum absorption. In order to obtain sufficient vacuum absorbing performance, the vertical length of the vacuum absorbing panel 8 is preferably 70% or more of the total length of the trunk portion 3 in the vertical direction.

On the other hand, if the portion of the wall surface of the trunk portion 3 occupied by the concave or flat vacuum absorbing panel 8 is too large, the cross-sectional shape of the trunk portion 3 becomes substantially polygonal. Therefore, in the present invention, the total circumference A of all pillars in the cross section of the body 3 is set to 20% or more of the total circumference B of the perfect circle, and the number of pressure reduction absorption panels is eight, thereby reducing the shrinkage. The outer appearance of the body 3 on which the label is attached can be a cylinder close to a perfect circle 10.例文帳に追加If the number of vacuum absorption panels 8 is small, the size of each vacuum absorption panel 8 must be increased in order to obtain vacuum absorption performance. It becomes difficult for the external appearance of the portion 3 to present a cylinder close to the perfect circle 10 . On the other hand, if the number of vacuum absorption panels 8 is large, each vacuum absorption panel 8 becomes small and the vacuum absorption performance is greatly reduced, so that the required vacuum absorption performance cannot be obtained. Therefore, in consideration of these circumstances, in the present invention, the number of decompression absorption panels (8) and the ratio of the total circumference A of all columns in the cross section of the body 3 to the total circumference B of the perfect circle ( 20% or more, that is, two times or more than the conventional bottle).

As shown in FIGS. 4 and 5, a shrink label 11 made of a heat-shrinkable film is attached to the outer surface of the body portion 3 of the synthetic resin bottle 1 of this embodiment. As shown, the shrink label 11 is mainly attached to the arc-shaped wall surface 9a of the column portion 9. As shown in FIG. Then, the recessed portion 8a of the decompression absorption panel 8 is covered with the recessed portion 8a in a slightly floating state without being in close contact with the recessed portion 8a. As a result, due to the shrink label 11, the external appearance of the body portion 3 is a cylinder close to a perfect circle 10.例文帳に追加However, the edge 9b (see FIG. 3), which is the boundary between the vacuum absorbing panel 8 and the column portion 9, is sharp, and when the shrink label 11 is pressed against the edge 9b, streaks extending in the vertical direction (vertical direction) are formed on the shrink label. 11, giving the impression of a polygonal rectangular tube. For this reason, it is preferable that the cross-sectional shape (see FIG. 3) of the end portion 8c of the decompression absorption panel 8 connected to the end edge 9b of the column portion 9 is formed into a rounded curved shape. By setting R(b) to 5 mm or more, the formation of the streaks described above is prevented, and the shrink label 11 does not interfere with the purpose of making the outer appearance of the body portion 3 a cylinder close to the perfect circle 10 . As a preferable example, the radius of curvature R(b) is about 10 mm.

[About heat deformation]
The synthetic resin bottle 1 of the present embodiment is filled with a beverage, sealed, heated to a temperature of, for example, about 50° C. to 60° C. by a hot warmer, a hot vendor, etc., and then sold. The internal pressure rises due to expansion of the content liquid or the like. Due to this increase in pressure, as schematically shown in the enlarged cross-sectional view of FIG. The horizontal cross-sectional shape becomes substantially arcuate along with 9a, and the body portion 3 of the synthetic resin bottle 1 presents a cylinder close to a perfect circle 10, and it is expected that the appearance will be a cylinder closer to a perfect circle 10. can. In FIG. 6, the shape of the concave portion 8a before deformation (before heating) is indicated by a broken line, and the shape of the concave portion 8a after deformation (after heating) is indicated by a solid line. As for the deformation of the recessed portion 8a of the vacuum absorbing panel 8, if the radius of curvature R(a) of the recessed portion 8a of the vacuum absorbing panel 8 is small, the recessed portion 8a bulges outward even if the synthetic resin bottle 1 is heated. Deformation is unlikely to occur, and the body portion 3 of the synthetic resin bottle 1 tends not to exhibit a cylinder close to the perfect circle 10 . On the other hand, if the radius of curvature R(a) of the concave portion 8a is large, the concave portion 8a bulges outward when the temperature of the synthetic resin bottle 1 becomes high, and the body portion 3 of the bottle 1 becomes a cylinder close to a perfect circle 10. show a tendency to

FIG. 7 shows the result of analysis of the shape of the concave portion 8a of the vacuum absorbing panel 8 after heating as described above. In the analysis, the curvature radius R(b) in the cross section of the end portion 8c of the reduced pressure absorption panel 8 was set to 3 mm, 6.5 mm, and 10 mm, and the curvature radius R(a) in the cross section of the concave portion 8a was set to FIG. 7 shows the amount of expansion of the concave portion 8a after heating in various combinations of the four settings of 10 mm, 15 mm, 25 mm, and 40 mm. The amount of bulge is defined as 0 mm when the wall surface is flat and straight with no bulges or dents, a negative value when the wall surface is concave inward, and a positive value when the wall surface is convex outward. ing. According to the analysis results shown in FIG. 7, the radius of curvature R(a) of the concave portion 8a is 10 mm or less in any of the cases where the radius of curvature R(b) of the end portion 8c of the decompression absorbing panel 8 is 3 mm, 6.5 mm, or 10 mm. In the case of , the concave portion 8a does not bulge outwardly when heated, and remains in an inwardly concave shape. Therefore, in these cases, the deformation due to heating does not contribute much to making the barrel portion 3 of the bottle 1 into a cylinder close to the perfect circle 10 . On the other hand, when the curvature radius R(a) of the concave portion 8a is 15 mm or more, the concave portion 8a projects outward during heating regardless of the curvature radius R(b) of the end portion 8c of the vacuum absorbing panel 8. It can be seen that this contributes to making the barrel portion 3 of the bottle 1 into a cylinder close to the perfect circle 10 . For this reason, in the synthetic resin bottle 1 of the present embodiment, in order to perform the above-described warming sales and to make the body portion 3 of the bottle 1 a cylinder close to the perfect circle 10, the recessed portion 8a of the pressure reduction absorption panel 8 It is effective that the radius of curvature R(a) of is 15 mm or more.

[Other embodiments]
FIG. 8 shows a synthetic resin bottle 20 according to a second embodiment of the invention. The synthetic resin bottle 20 has a large number of fine irregularities formed over the entire outer peripheral surface of the heel portion 2, the body portion 3, and the shoulder portion 4. As shown in FIG. A shape having such a large number of minute unevenness is referred to as an "embossed portion" here. In the synthetic resin bottle 1 of the first embodiment of the present invention described above, if such an embossed portion 12 is formed on the outer peripheral surface, the body portion 3 of the synthetic resin bottle can be further formed into a perfect circle 10. It is possible to give the impression of a near-cylindrical appearance. The reason will be explained below. Incidentally, the embossed portion may be formed at least on the body portion 3 .

One of the major factors that give the appearance of the body of the synthetic resin bottle the impression of a polygonal rectangular cylinder rather than a perfectly circular cylinder is the edge located at the boundary between the vacuum absorbing panel 8 and the column 9. 9b or its vicinity is recognized as a streak extending in the vertical direction (vertical direction). That is, when a line extending in the vertical direction is recognized, it is recognized that the shape of the body of the bottle is not a curved surface, but that planes are joined together, and the joint portion appears as a line extending in the vertical direction. As a result, the shape of the body portion of the synthetic resin bottle is recognized as a polygonal rectangular cylinder rather than a perfectly circular cylinder. Therefore, if the stripes extending in the vertical direction are made inconspicuous, it is easy to give the impression that the shape of the trunk is a perfectly circular cylinder. That is, as shown in FIG. 8, when the embossed portion 12 is provided on the outer peripheral surface of the body portion 3 of the synthetic resin bottle 20, the embossed portion can be formed even if longitudinally extending streaks are generated at or near the edge 9b. Since many minute irregularities of the portion 12 are visible to the eye, streaks are less noticeable. As a result, since the streaks are difficult to recognize, the shape of the torso gives the impression of a perfectly circular cylinder. In the synthetic resin bottle of this embodiment, the optical illusion is intentionally used to effectively give the impression that the shape of the body portion 3 of the synthetic resin bottle 20 is a cylinder close to the perfect circle 10. can be done. In particular, in addition to setting the curvature radius R(b) shown in FIG. 3 to 5 mm or more as described above, if the embossed portion 12 shown in FIG. more effective in giving the impression that From this point of view, the embossed portion 12 should be provided at least only on the edge 9b and its vicinity. However, it is preferable to form the embossed portion 12 on the entire outer peripheral surface of the body portion 3 in order to avoid a large difference in appearance impression between the embossed portion 12 and other portions. In addition, the embossed portion 12 makes it difficult for the purchaser to feel the heat when holding the synthetic resin bottle 20 when the synthetic resin bottle 20 is filled with a beverage, sealed, and sold while being heated. It also has the effect of making it difficult to convey

In the example shown in FIG. 8, the embossed portion 12 is formed by forming a plurality of mutually intersecting thin groove-shaped concave portions, thereby forming about 1 to 8 (4.5 as an example) convex portions per 1 cm ² . It is formed. Therefore, the depth of the recess is about 0.1 to 0.5 mm (0.3 mm as an example).

Also in the synthetic resin bottle 20 of the present embodiment, the total circumference A of all the columns in the cross section of the body 3 is 20 to 50% of the total circumference B of the perfect circle. Other configurations are the same as those of the first embodiment described above, so description thereof will be omitted.

[Modification]
Although the synthetic resin bottle of each of the embodiments described above has the vacuum absorbing panel 8 that extends along the vertical direction, it can also have the vacuum absorbing panel 8 that is inclined with respect to the vertical direction. In that case, the columnar portion 9 also has a shape inclined with respect to the vertical direction. It is preferable that the inclination angle with respect to the vertical direction is 30 degrees or less.

1 Synthetic resin bottle 2 Heel 3 Body 4 Shoulder 5 Neck 6 Male screw 7 Screw cap 8 Vacuum absorption panel 8a Recess 8b Circumferential center 8c End 9 Column 9a Arc-shaped wall surface 9b Edge 9c Circumferential center 10 Virtual perfect circle 11 Shrink label 12 Embossed part

Claims (8)

In a synthetic resin bottle for aseptic filling, having a cylindrical body,
Eight vacuum absorption panels arranged at regular intervals on the body, and pillars made up of arc-shaped wall surfaces respectively arranged between the vacuum absorption panels,
The vacuum absorption panel absorbs the vacuum after filling the room temperature liquid and sealing the synthetic resin bottle,
The arc-shaped wall surface of the pillar in the cross section of the trunk constitutes a part of one virtual perfect circle, and the total circumference of the arc-shaped wall surface of the pillar is the total circumference of the perfect circle. 20 to 50% of
A synthetic resin bottle characterized in that, in the lateral cross section of the body portion, the end portion of the vacuum absorption panel connected to the circumferential edge of the column portion is a curve with a radius of curvature of 5 mm or more. In a synthetic resin bottle for aseptic filling, having a cylindrical body,
Eight vacuum absorption panels arranged at regular intervals on the body, and pillars made up of arc-shaped wall surfaces respectively arranged between the vacuum absorption panels,
The vacuum absorption panel absorbs the vacuum after filling the room temperature liquid and sealing the synthetic resin bottle,
The arc-shaped wall surface of the pillar in the cross section of the body constitutes a part of one virtual perfect circle, and the radial line passing through the circumferential center of the pillar and the circumferential direction of the pillar The angle formed by the radial line passing through the edge is the angle formed by the radial line passing through the circumferential center of the column and the radial line passing through the circumferential center of the pressure reduction panel adjacent to the column. 20 to 50%,
A synthetic resin bottle characterized in that, in the lateral cross section of the body portion, the end portion of the vacuum absorption panel connected to the circumferential edge of the column portion is a curve with a radius of curvature of 5 mm or more. 3. The synthetic resin bottle according to claim 1 or 2, wherein said vacuum absorption panel has a concave portion including a curved line with a radius of curvature of 15 mm or more in the cross section of said body portion. In a synthetic resin bottle for aseptic filling, having a cylindrical body,
Eight vacuum absorption panels arranged at regular intervals on the body, and pillars composed of arc-shaped wall surfaces respectively arranged between the vacuum absorption panels,
The vacuum absorption panel absorbs the vacuum after filling the room temperature liquid and sealing the synthetic resin bottle,
The arc-shaped wall surface of the pillar in the cross section of the trunk constitutes a part of one virtual perfect circle, and the total circumference of the arc-shaped wall surface of the pillar is the total circumference of the perfect circle. 20 to 50% of
A synthetic resin bottle, wherein, in the cross section of the body portion, the vacuum absorption panel has a concave portion including a curve with a radius of curvature of 15 mm or more. In a synthetic resin bottle for aseptic filling, having a cylindrical body,
Eight vacuum absorption panels arranged at regular intervals on the body, and pillars made up of arc-shaped wall surfaces respectively arranged between the vacuum absorption panels,
The vacuum absorption panel absorbs the vacuum after filling the room temperature liquid and sealing the synthetic resin bottle,
The arc-shaped wall surface of the pillar in the cross section of the body constitutes a part of one virtual perfect circle, and the radial line passing through the circumferential center of the pillar and the circumferential direction of the pillar The angle formed by the radial line passing through the edge is the angle formed by the radial line passing through the circumferential center of the column and the radial line passing through the circumferential center of the pressure reduction panel adjacent to the column. 20 to 50%,
A synthetic resin bottle, wherein the vacuum absorption panel has a concave portion including a curved line with a radius of curvature of 15 mm or more in the cross section of the body portion. The synthetic resin bottle according to any one of claims 3 to 5, which is sold hot. 7. The synthetic resin bottle according to any one of claims 3 to 6, wherein said recess is filled with a content, sealed, and heated to 50[deg.] C. or higher to bulge outward. An embossed portion is provided on at least the portion of the outer peripheral surface of the body portion that includes the circumferential edge of the column portion, and the embossed portion forms a recess with a depth of 0.1 to 0.5 mm. 8. The synthetic resin bottle according to any one of claims 1 to 7, wherein 1 to 8 protrusions are formed per 1 cm ² by pressing.

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