JP2008247409A - Synthetic resin container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a synthetic resin container in which some corrugations formed at a pressure reducing and absorbing panel are made thick at their walls, other remaining portions are made thin at their walls to restrict a bulging-out state of the container at the time of filling while the entire strength of the pressure reducing and absorbing panel is being prevented from being decreased and a volumetric variation generated through its cooling after filling operation is absorbed. <P>SOLUTION: A bottle 1 has a pressure reducing and absorbing panel 10 with a part of a long-side wall W1 being concave inwardly, wherein the panel 10 includes a center panel 11 deeper than the wall W1, two side panels 12, 13 deeper than that of the center panel 11 and extending in the direction of the axis O, an upper panel 14 deeper than those of the side panels 12, 13 and extending along the two side panels 12, 13, and a core panel 15 deeper than those of the side panels 12, 13, extending along the two side panels 12, 13 and having the same depth as that of the upper panel 14 or a depth different from that of the upper panel 14. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a synthetic resin container having a vacuum absorbing panel in which a part of a peripheral wall is recessed inward.

  Synthetic resin containers typified by PET bottles, when the contents are filled in a heated state such as fruit juice drinks or tea, will swell once during filling, but the internal pressure decreases as the contents are cooled, There is a problem that deformation accompanied by a decrease in volume occurs.

On the other hand, in a conventional synthetic resin container, a part of the peripheral wall is recessed inward to form a reduced pressure absorption panel. Further, the reduced pressure absorption panel has two concave vertical ribs spaced in the circumferential direction. And the wall surface between the vertical ribs bulge outward (see, for example, Patent Document 1).
Japanese Patent No. 3826830

  However, when the container is formed, the uneven portion tends to be thick, resulting in a thin portion in the peripheral portion and the like, which causes a problem that mechanical strength is reduced.

  Further, if there are irregularities in the vacuum absorbing panel, there is a possibility that the panel behavior becomes unstable due to the influence of the wall thickness, or that the good vacuum absorbing ability cannot be exhibited.

  There is a problem that the above-described problem appears remarkably when trying to reduce the weight of the container.

  Further, the inventor of the present application recognizes that the central portion of the vacuum absorbing panel is likely to be deformed as the internal pressure is decreased, and that the rectangular vacuum decompressing panel is particularly likely to be deformed along the axis of the peripheral wall. It came to do.

  The problem to be solved by the present invention is that, when forming a concavo-convex portion in a vacuum absorbing panel, the concavo-convex portion becomes thick, while the thin portion is formed in the other portion, so that the function of the entire vacuum absorbing panel is exhibited. The purpose of the present invention is to provide a synthetic resin container that suppresses the swelling generated during filling without absorbing the function of the vacuum absorption panel and absorbs the volume change caused by cooling after filling. It is in.

  The present invention is a synthetic resin container having a vacuum absorption panel in which a part of the peripheral wall is recessed inward, wherein the vacuum absorption panel is disposed near the center of the vacuum absorption panel and the depth thereof is greater than that of the peripheral wall. A deep center panel portion, two side panel portions disposed on both sides of the center panel and having a depth deeper than the center panel portion and extending along the axial direction of the peripheral wall, and disposed above the center panel portion. The upper panel part that is deeper than the side panel part and extends along the two side panel parts, and the two side panel parts that are arranged below the center panel part and deeper than the side panel part And a lower panel portion extending along the line.

  Examples of the peripheral wall according to the present invention include a cylindrical shape and a polygonal column shape. In addition, the shape of the vacuum absorbing panel may be an elliptical shape or a polygonal shape.

  According to this invention, the depth of an upper panel part and a lower panel part can be changed suitably. That is, according to the present invention, even if the depth between the upper panel portion and the lower panel portion is changed and the depth with respect to the peripheral wall is changed, the upper panel portion and the lower panel portion are made to have the same depth to the peripheral wall. It is also possible to have the same depth.

  In addition, if the two side panel portions also have a portion extending along the axial direction of the peripheral wall, the upper panel connects the corresponding upper and lower ends as well as independent ones parallel to each other along the axial direction. It is good also as a shape which encloses a part, a center panel part, and a lower panel part cyclically | annularly.

  According to the present invention, the reduced pressure absorption panel is divided into a total of five parts, an upper panel part, a center panel part, and a lower panel part sandwiched between two side panel parts, and the center panel part protrudes from the side panel part. On the other hand, since the upper panel portion and the lower panel portion are recessed with respect to the side panel portion, the two side panel portions increase the strength (column strength) in the axial direction of the vacuum absorbing panel, while the two side panel portions By deepening the upper panel portion and the lower panel portion existing between the two, the rigidity on the upper side and / or the lower side of the vacuum absorption panel is increased, so that the center existing in the central part that is most movable in the vacuum absorption panel is present. Since the movement in the panel part is suppressed, it shows good deformation behavior and effectively fills without reducing the strength of the vacuum absorption panel. Bulge and suppression occurs sometimes can absorb the volume change caused by cooling after filling.

  In addition, according to the present invention, it is possible to suppress a sudden change in thickness due to the uneven shape formed in the reduced pressure absorption panel. Further, according to the present invention, the entire reduced pressure absorption panel has a good thickness distribution. Therefore, nonuniform deformation can be prevented.

  Further, according to the present invention, the depths of the upper panel portion and the lower panel portion can be appropriately changed.

  For example, when the deformation amount due to the decrease in internal pressure is different between the upper side and the lower side of the reduced pressure absorption panel, the depth of the upper panel portion or the lower panel portion on the side with the larger deformation amount becomes deeper than the other panel portion. In other words, in other words, the upper panel portion or the lower panel portion on the side with the larger deformation amount is set to be deepest with respect to the peripheral wall.

  As a specific example, when a waist part as an annular recess is formed on the upper side or the lower side of the vacuum absorption panel in the peripheral wall, the depth of the upper panel part or the lower panel part on the side where the waist part is formed is the peripheral wall. Set to be deepest against.

  In this way, when the deformation amount due to the decrease in internal pressure is different between the upper side and the lower side of the reduced pressure absorption panel, the upper panel portion and the lower panel portion are adjusted so that the depth on the larger deformation amount side becomes the deepest. If the depth is made different, the amount of deformation generated on the upper side and the lower side of the reduced pressure absorption panel can be adjusted in a well-balanced manner without reducing the strength of the reduced pressure absorption panel.

  However, the phenomenon in which the amount of deformation associated with the decrease in the internal pressure increases on the upper and lower sides of the reduced pressure absorption panel does not necessarily depend only on the presence of the waist portion.

  On the other hand, according to the present invention, the upper panel portion and the lower panel can be used even when the deformation amount due to the decrease in the internal pressure is different between the upper side and the lower side of the vacuum absorbing panel due to the shape of the container other than the presence of the waist portion. If the depth with the portion is appropriately adjusted to make a difference in the depth, the amount of deformation generated between the upper side and the lower side of the reduced pressure absorption panel can be made uniform.

  Further, according to the present invention, when the amount of deformation accompanying the decrease in the internal pressure is the same on the upper side and the lower side of the reduced pressure absorption panel, the depth of the upper panel portion and the lower panel portion is the same, and the depth to the peripheral wall is the same. It is also possible to make it.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a front view showing a PET bottle (hereinafter referred to as “bottle”) 1 according to an embodiment of the present invention. FIGS. 2 (a) to 2 (c) are cross-sectional views taken along line AA in FIG. , BB sectional drawing and CC sectional drawing are shown. 3 (a) and 3 (b) are an enlarged perspective view of the vacuum absorbing panel 10 shown in FIG. 1 and a YY sectional view of FIG. 3 (b).

  The bottle 1 is formed by performing a biaxial stretch blow molding of a preform made of a PET (polyethylene terephthalate) resin, and as shown in FIG. 2, the cross section is alternately arranged with long side walls W1 and short side walls W2. A peripheral wall having a substantially octagonal shape, one of which constitutes a mouth portion 1a for filling and pouring the contents, and the other one constitutes a bottom portion 1b having an annular ground surface that closes the inside of the peripheral wall.

  Further, the peripheral wall has a shoulder portion 1c that expands from the mouth portion 1a toward the bottom portion 1b along the axis O, and a body that extends in parallel along the axis O from the ridge line L where the expansion of the shoulder portion 1c is maximized. A waist portion 1w is formed as an annular recess in the body portion 1d.

  Of the body part 1d divided by the waist part 1w, the body part 1d on the mouth part 1a side is recessed inwardly on the four long side walls W1 facing each other (axis O side). A vacuum absorbing panel 10 is formed.

  As shown in FIG. 1, the reduced pressure absorption panel 10 includes a center panel portion 11 disposed near the center of the reduced pressure absorption panel 10 and two side panel portions 12, 13 disposed on both sides of the center panel 11. The upper panel portion 14 disposed on the upper side of the center panel portion 11 and the lower panel portion 15 disposed on the lower side of the center panel 11 are vertically long rectangular panels extending along the axis O.

  Specifically, the center panel portion 11 has a rectangular flat plate shape, and the depth is deeper by D1 than the long side wall W1 as shown in FIG. 3 (b).

  As shown in FIG. 2, each of the side panel portions 12 and 13 has the same depth, and becomes deeper by D2 (w) than the long side wall W1, and as shown in FIG. It is deeper by D2 (11) than the center panel portion 11, and extends along the direction of the axis O as shown in FIGS. In FIG. 2, only one of the four vacuum absorption panels 10 is exemplarily shown in detail with reference numerals.

  As shown in FIG. 3 (b), the upper panel portion 14 is deeper by D4 (w) than the long side wall W1, and as shown in FIG. 2 (a), the side panel portions 12, It is deeper than D13 by D4 (12), and extends along the two side panel portions 12, 13 as shown in FIG. 1 and FIG.

  As shown in FIG. 3 (b), the lower panel 15 is deeper than the long side wall W1 by D5 (w), and as shown in FIG. Is deepened only by D5 (12), and extends along the two side panel portions 12 and 13, as shown in FIG. 1 and FIG. 3 (a).

  According to the bottle 1 according to the present embodiment, the two side panel portions 12 and 13 are suppressed while suppressing a sudden change in thickness due to the uneven shape formed by the panel portions 11 to 15 formed in the vacuum absorbing panel 10. Increases the strength (column strength) of the vacuum absorption panel 10 in the direction of the axis O, while the upper panel portion 14 and the lower panel portion 15 existing between the two side panel portions 12 and 13 are deepened, thereby reducing the pressure absorption panel 10. As the rigidity on the upper side and / or the lower side of the pressure reducing panel 10 is increased, the movement of the center panel portion 11 existing in the central part that is most movable among the reduced pressure absorbing panel 10 is suppressed. Good deformation behavior can be exhibited without lowering the volume, effectively suppressing the bulging that occurs during filling, and absorbing volume changes caused by cooling after filling.

  Moreover, according to the bottle 1 which concerns on this form, it becomes possible to suppress the sudden thickness change resulting from the uneven | corrugated shape formed in the decompression absorption panel 10, Furthermore, according to the bottle 1, the decompression absorption panel 10 whole Since the thickness distribution is good, non-uniform deformation can be prevented.

  Further, in the present embodiment, as shown in FIG. 3 (b), in the container in which the waist portion 1w is formed, the depth of the lower panel portion 15 adjacent to the waist portion is set to ΔD more than the upper panel portion 14. The lower panel portion 15 is set to be deepest with respect to the long side wall W1 by making it deeper.

  In a container (bottle), the portion located at the central height portion of the container is most easily affected by the influence of the internal pressure of the container, while in the vacuum absorption panel, the central height of the panel is concerned. When the part located in the part is greatly affected by the internal pressure of the container and is most movable, the waist part is formed at the central height part of the container and the vacuum absorbing panel is provided at a position close to the waist part. This is because, in this reduced pressure absorption panel, the amount of deformation also increases on the upper side or the lower side of the panel close to the waist portion (the lower side where the lower panel portion 15 exists in this embodiment).

  At this time, the depth D5 (w) of the lower panel portion 15 with respect to the long side wall W1 is preferably set to 2 to 3 mm. In FIG. 3 (b), the symbol D4 (11) is the difference in the depth of the upper panel portion 14 with respect to the center panel portion 11, and the symbol D5 (11) is the lower panel portion 15 with respect to the center panel portion 11. Is the difference in depth.

  As described above, when the deformation amount due to the decrease in the internal pressure is different between the upper side and the lower side of the reduced pressure absorption panel 10, the depth on the larger side of the deformation amount (in this embodiment, the lower panel portion 15 on the waist portion 1w side). If the depth D5 (w) is adjusted to be the deepest and a difference ΔD is added to the depth between the upper panel portion 14 and the lower panel portion 15, the reduced pressure absorption panel 10 is not reduced without reducing the strength of the reduced pressure absorption panel 10. The amount of deformation that occurs between the upper side and the lower side of can be adjusted in a balanced manner.

  However, the phenomenon that the deformation amount due to the decrease in the internal pressure increases on the upper side and the lower side of the reduced pressure absorption panel 10 does not necessarily depend only on the presence of the waist portion 1w as in the present embodiment.

  On the other hand, according to the present invention, even when the amount of deformation due to the decrease in the internal pressure differs between the upper side and the lower side of the vacuum absorbing panel 10 due to the shape of the container other than the presence of the waist portion 1w, the upper panel portion By appropriately adjusting the depths of 14 and the lower panel portion 15 and making a difference between the depths, the amount of deformation generated between the upper side and the lower side of the vacuum absorbing panel 10 can be adjusted in a balanced manner.

  Further, in this embodiment, the surface area of the lower panel portion 15 is set to be smaller than that of the upper panel portion 14 in order to further increase the rigidity and suppress the movement of the lower panel portion 15 on the side where the waist portion 1w is formed. . However, this relationship also does not prevent the surface areas of the upper panel portion 14 and the lower panel portion 15 from becoming the same, or the surface area of the upper panel portion 14 from becoming smaller than the lower panel portion 15.

  FIG. 4 is a front view showing a modified example of the bottle 1, which is another embodiment of the present invention, and the same parts as those in FIGS.

  In the present embodiment, the upper panel portion 14, the center panel portion 11 and the lower panel portion 15 are annularly surrounded by connecting the upper and lower ends corresponding to each other in the two side panel portions 12 and 13, as viewed from the front of the long side wall W1. It has a shape.

  The above description shows preferred forms of the present invention, but various modifications can be made within the scope of the claims.

  For example, according to the present invention, the upper panel portion 14 and the lower panel portion 15 have the same depth with respect to the long side wall W1 when the amount of deformation accompanying the decrease in the internal pressure is the same between the upper side and the lower side of the vacuum absorbing panel 10. It is also possible to set D4 (11) = D5 (11), that is, D4 (w) = D5 (w)).

  Further, the shape of the container according to the present invention is not limited to the polygonal column shape, and various shapes such as a cylindrical shape can be adopted. Furthermore, according to this invention, it is applicable also to the bottle which does not provide a waist part.

It is a front view which shows the PET bottle which is one form of this invention. (a)-(c) is respectively AA sectional drawing of FIG. 1, BB sectional drawing, and CC sectional drawing. (a), (b) is each a perspective view which expands and shows the decompression absorption panel shown in FIG. 1, and YY sectional drawing of the same figure (b). It is a front view which shows the modification of the bottle of FIG. 1 which is the other form of this invention.

Explanation of symbols

1 PET bottle (synthetic resin container)
1a mouth
1b Bottom
1c shoulder
1d torso
1w waist
10 Vacuum absorption panel
11 Center panel
12 Side panel section
13 Side panel section
14 Upper panel
15 Lower panel section
D1 Depth of center panel relative to long side wall
D2 (11) Depth of side panel relative to center panel
D4 (12) Depth of upper panel relative to side panel
D5 (12) Depth of lower panel relative to side panel
W1 Long side wall
W2 short side wall

Claims (3)

A synthetic resin container having a vacuum absorbing panel with a part of the peripheral wall recessed inside,
The vacuum absorbing panel is disposed near the center of the vacuum absorbing panel and has a center panel portion whose depth is deeper than the peripheral wall, and is disposed on both sides of the center panel and has a depth deeper than the center panel portion. Two side panel portions extending along the axial direction, an upper panel portion disposed on the upper side of the center panel portion and having a depth deeper than the side panel portion and extending along the two side panel portions, and a center A synthetic resin container comprising: a lower panel portion disposed below the panel portion and having a depth deeper than the side panel portion and extending along the two side panel portions.   The synthetic resin container according to claim 1, wherein a height difference is provided between the height of the upper panel portion and the lower panel portion.   The synthetic resin container according to claim 1, wherein the upper panel portion and the lower panel portion have the same height.

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