AU2015200602B2 - Bottle - Google Patents

Abstract

Abstract A bottomed tubular bottle comprising: an annular groove which is formed so as to be circumferentially and radially recessed inward along the outer peripheral surface of a body of the bottle with the bottle axis as a center and which contracts and deforms the body in the axial direction of the bottle axis when the internal pressure is reduced, wherein the annular groove is formed in the shape of the letter V by two facing wall surfaces, a protrusion is formed on at least one wall surface of the wall surfaces, and the protrusion has a ridgeline which extends toward the outer peripheral surface of the body while being orthogonal to the circumferential direction of the wall surface when the wall surface on which the protrusion is formed is seen in plane view.

Description

I DESCRIPTION Title of Invention BOTTLE [0001] The present application is a divisional application from Australian Patent Application No. 2009280614, the entire disclosure of which is incorporated herein by reference. Technical Field [000 la] The present invention relates to a bottle, and particularly, to a bottle formed from synthetic resin, That is, the present invention relates to a compressively deformable bottle including a body and a bottom connected to the body via a heel, which are integrally molded, and absorbing the deformation accompanying a reduction in internal pressure by compressively deforming a portion of the bottle itself. Priority is claimed on Japanese Patent Application No. 2.008-33'2491 filed on December 26, 2008, Japinese Patent Application No, 2008-305227 filed on November 28, 2008, and Japanese Patent Application No. 2008-208191 filed on August 12 2008, the contents of which are incorporated herein by reference. Background Art [0002) A reference herein to a patent document or other matter which is given as prior art is not to be taken as an admission that that document or matter was known or that the information it contains was part of the common general knowledge as at the priority date of any of the claims, [0002a] Throughout the description and claims of the specification, the word Ia "comprise" and variations of the word, such as "comprising" and "comprises", is not intended to exclude other additives, components., integers or steps. [0002bi Since bottles made of synthetic resin which are represented by PET bottles are inexpensive in terms of costs, in addition to being lightweight and easy to handle, and assuming an appearance which is in no way inferior to glass containers while ensuring transparency, the bottles are mainly used as beverage containers. Meanwhile, this kind of bottle has the disadvantage that because the thickness of the body is thin, when the inside of the bottle is brought into a pressure-reduced state, the body is deformed in irregular shapes, such as an elliptical or a triangular shape. In a 2 case where the body has been deformed in this way, there is a problem in that not only is the aesthetic appearance impaired, but the operability is poor. Particularly in a case where the bottle is made lightweight by reducing its thickness, this problem becomes more conspicuous, 5 [0003] Thus, in order to suppress irregular deformation of the body caused when the internal pressure of the container drops (pressure is reduced), a bottle in which the body is provided with a pressure-reduction absorption panel is developed. However, since this type of bottle is inevitably restricted by the pressure-reduction absorption panel at the 10 time of design, freedom of design is not possible, and problems are left unsolved in terms of design performance. [0004] Apart from tbis, an unpanelled bottle which can suppress irregular deformation of a body at the time of pressure reduction without providing the body with a 15 pressure-reduction absorption panel has recently been provided (see Patent Document 1 and Patent Document 2). This bottle is a bottle in which an annular groove is formed in the outer peripheral surface of the body, and the body is capable of being contracted and deformed in the axial direction (longitudinal direction) with the annular groove as a center. That 20 is, this bottle is designed so that a pressure change at the time of pressure reduction can be absorbed by contracting and deforming the body in the axial direction. Additionally, as the compressively deformable bottle, for example, there is a heat-filled bottle (for example, refer to Patent Document 3) including a mouth, a cylindrical neck tube connected via a neck ring provided in the mouth, a shoulder which 25 is enlarged in diameter integrally from the neck tube, a body connected to the shoulder, 3 and a bottom connected to the body via a heel, which are integrally molded, Here, an annular recess which splits the body into an upper portion and a lower portion is formed by recessing a portion of the body radially inward along the circumference of an axis, and the deformation accompanying a pressure reduction effect after cooling is absorbed by making an upper surface of the annular recess connected to the upper portion foldable toward a lower surface of the annular recess connected to the lower portion. Related Art Document Patent Document [0005] Patent Document 1: Japanese Unexamined Patent Application, First Publication No, 2005-280755 Patent Document 2: Japanese Unexamined Patent Application, First Publication No. 2004-262500 Patent Document 3: Published Japanese Translation No. 2004-507405 of the PCT International Publication [0006] However, irregular deformation may be caused such as bending of the neck when the mouth side of the bottle may be bent depending on the degree of contracted deformation when the inside of the bottle is brought into a pressure-reduced state, and appearance degradation may result. Otherwise, in a case where the inside of the bottle is actually brought into a pressure-reduced state, the bottle not only tends to be contracted and deformed in the axial direction, but also tends to be contracted and deformed more than a little even in the radial 4 direction. That is, the pressure which will contract the bottle in the axial direction and the pressure which will contract the bottle in the radial direction will act on the bottle simultaneously. In these pressures, the pressure which will contract the bottle in the axial direction can be absorbed as the bottle is contracted and deformed with the annular groove as a center, the pressure which will contract the bottle in the radial direction may not be able to be absorbed by the portion of the annular groove. Therefore, folded wrinkles may be created in the annular groove. If these folded wrinkles are created, the folded wrinkles may be plastically deformed, and appearance degradation or a decrease in the restoring force of the bottle (such as at the time of cap opening) may occur. Additionally, even in the heat-filled bottle as disclosed in Patent Document 3, actually, the upper Surface of the annular recess is not folded equally toward the lower surface thereof, but the upper portion of the body may be deformed in the state of being inclined with respect to the axis. Since such a deformation is recognized as contributing to poor appearance, there is room for further improvement. [0007] It is therefore desirable to provide a bottle which can be contracted and deformed in the axial direction, thereby effectively absorbing a pressure change generated at the time of pressure reduction and which can suppress irregular deformation, such as bending of the neck at the tine of contraction and deformation. It is also desirable to provide a bottle which can be contracted and deformed in the axial direction while suppressing the creation of folded wrinkles at the time of pressure reduction and which can reliably absorb a pressure change caused at the time of pressure reduction, 5 Summary of the Invention [0008] According to the present invention, a bottomed tubular bottle comprising: an annular groove which is formed so as to be circumferentially and radially recessed inward along the outer peripheral surface of a body of the bottle with the bottle axis as a center and which contracts and deforms the body in the axial direction of the bottle axis when the internal pressure is reduced, wherein the annular groove is formed in the shape of the letter V by two facing wall surfaces, a protrusion is formed on at least one wall surface of the wall surfaces, and the protrusion has a ridgeline which extends toward the outer peripheral surface of the body while being orthogonal to the circumferential direction of the wall surface when the wall surface on which the protrusion is formed is seen in plane view. [0009] PARAGRAPH IS INTENTIONALLY LEFT BLANK.

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8 [0015] PARAGRAPH INTENTIONALLY LEFT BLANK. [0016] In the bottle according to the aspect of the present invention, since the annular groove is circumferentially recessed and torrned in the body, the body is contracted and deformed in the axial direction with the annular groove as a center when the internal pressure is reduced. Thereby, a pressure change at the time of pressure reduction can be absorbed by the axial contraction of the bottle. Moreover, since the annular groove is formed in the shape of the letter V by the two wall surfaces, the body is easily contracted and deformed in the axial direction with the annular groove therebetween. Hence, the above pressure change can be immediately absorbed with an immediate reaction. On the other hand. since the bottle receives the pressure which will contract the bottle in the radial direction independently from the pressure which will contract the bottle in the axial direction at the time of pressure reduction, the portion of the annular groove s pulled radially inward. However, the protrusion is formed on at least one wall surface of the two wall surfaces which constitute the annular groove. Therefore, it is considered that the state, where elastic deformation with the protrusion as a base point easily occurs, is locally formed. Accordingly, it is considered that the pressure which 9 will contract the bottle in the radial direction can be absorbed by the elastic deformation. [0017] Thereby, an internal pressure change caused at the time of pressure reduction can be reliably absorbed. Accordingly, it is possible to suppress creation of folded 5 wrinkles in the annular groove. Hence, the probability that plastic deformation in which a portion of the surface of the bottle bends may be caused at the time of pressure reduction can be suppressed. [0018] Additionally, in the bottle according to the above aspect of the present invention, 10 a plurality of the protrusions may be formed at regular intervals in the circumferential direction. [0019] In the bottle according to the above aspect of the present invention, since the plurality of protrusions is formed on at least one wall surface of the two wall surfaces 15 which constitute the annular groove, the protrusions which are formed at regular intervals in this circumferential direction respond to a pressure change equally in a well-balanced manner. Accordingly, it is possible to further reduce a probability that folded wrinkles may be created in the annular groove. [0020] 20 Additionally, in the bottle according to the above aspect of the present invention, the protrusion may be formed so as to enter closer to the annular groove side than the outer peripheral surface of the body. [0021] In the bottle according to the above aspect of the present invention, the 25 protrusion is formed in a state where the protrusion is completely stored in the wall 10 surface. Therefore, the protrusion is designed so that a portion thereof is not exposed to the outer peripheral surface side of the body. Accordingly, the protrusion hardly comes into direct contact with other bottles or the like. Therefore, the protrusion can be prevented from being accidentally recessed in advance. Additionally; since the 5 protrusion does not come into contact with a connecting corner which is a boundary line between the outer surface (outer peripheral surface of the body) of the bottle and the wall surface, creation of folded wrinkles can be prevented from being induced at the connecting corner in advance. [0022] 10 Additionally, in the bottle according to the above aspect of the present invention, a recess which accommodates the protrusion may be fonned at a position which faces the protrusion on at least the other wall surface of the two wall surfaces when both the wall surfaces approach each other in the axial direction of the bottle axis. [0023] 15 In the bottle according to the above aspect of the present invention, since the recess which accommodates the protrusion is formed at a position which faces the protrusion, even if the body is contracted and deformed to such a degree that the annular groove is crushed, the protrusion can be prevented from interfering with the wall surface. When the internal pressure is reduced, the body is contracted and deformed in 20 the axial direction with the annular groove as a center, thereby absorbing a pressure change within the bottle. However, in a case where this pressure change is comparatively large, the body is contracted and deformed to such a degree that the annular groove is crushed. In this case, the protrusion may interfere with the wall surface and may hinder contraction deformation of the body. 25 However, since the recess in which the protrusion is accommodated is formed as 11 described above, the probability that the protrusion may interfere with the wall surface and hinder contraction deformation of the body can be eliminated, [0024] Additionally, in the bottle according to the above aspect of the present invention, the recess may be formed so as to enter closer to the annular groove side than the outer peripheral surface of the body. [0025] In the bottle according to the above aspect of the present invention, the recess is formed in a state where the recess is completely stored in the wall surface. Therefore, the recess is designed so that a portion thereof is not exposed to the outer peripheral surface side of the body. Accordingly, the recess hardly comes into direct contact with other bottles. Thereby, the local deformation which may be caused in a case where the recess comes into contact with other bottles or the like can be prevented in advance. [0026] This paragraph is intentionally left blank. [0027] In the bottle according to the above aspect of the present invention, the protrusion is formed in a shape having one ridgeline. Moreover, the ridgeline extends toward the outer peripheral surface of the body in a state where the ridgeline is orthogonal to the circumferential direction of the wall surface when this ridgeline is seen in plane view. That is, the ridgeline extends radially outward when the body is seen from the axial direction of the bottle axis. Therefore, the protrusion is in the state of 12 being easily deformed with this ridgeline as a base point. Accordingly, it is considered that the elastic deformation with the protrusion as a base point occur more smoothly. Thereby, an internal pressure change caused at the time of pressure reduction is easily and more reliably absorbed, 5 [0028] PARAGRAPH INTEND TONALLY LEFT BLANK. [0029] PARAGRAPH INTENTIONALLY LEFT BLANK.

13 THIS PAGE IS INTENTIONALLY LEFT BLANK 14 THIS PAGE IS INTENTIONALLY LEFT BLANK, 15 PARAGRA FPHS [035] to [0038] iNTENTION ALLY LEFT BLAN K Effects of the invention 5 16 [0039] According to the bottle related to the aspect of the present invention, a pressure change caused at the time of pressure reduction can be absorbed by axial contraction deformation. In addition to this, since the body on the mouth side is stably supported by 5 the body on the bottom side even in a case where contraction deformation has occurred to such a degree that the annular groove is crushed, irregular deformation, such as bending of the neck, can be suppressed. Moreover, according to the bottle related to the aspect of the present invention, the bottle can be contracted and deformed in the axial direction while suppressing the 10 creation of folded wrinkles at the time of pressure reduction, and a pressure change caused at the time of pressure reduction can be absorbed reliably. Moreover, in the aspect of the present invention, as the internal pressure of the bottle is reduced or an external force is applied to the bottle in the direction of the axis, the bottle can be easily compressed and deformed in the direction of the axis. 15 Furthermore, according to the aspect of the present invention, even after the upper surface of the second annular recess is folded toward the lower surface thereof, the folded state can be maintained, Since the folded state is not related to whether or not the bottle is in a pressure-reduced state, contents can also be filled in a state where the bottle is folded and compressed in advance. 20 Accordingly, in the bottle according to the aspect of the present invention, the body of the bottle is equally folded in the direction of the axis and the folded state is maintained even if the internal pressure of the bottle is reduced. Therefore, it is possible to provide to the market or the like a bottle which has an aesthetic outward appearance, and is beautiful. 25 In addition, it is considered that the reason why the folding in the second annular 17 recess becomes easy is because the rigidity in the first annular recess formed above the second annular recess 2 is high, the first annular recess is not buckled, the larger diameter portion spreads radially outward, and thereby the second annular recess easily bends radially inward. On the other hand, it is considered that the reason why the folded state 5 in the second annular recess is maintained is because the first annular recess with high rigidity prevents its restoration if the larger diameter portion spreads radially outward and the second annular recess is bent once. For this reason, in the present invention, if the maximum depth of the first annular recess is set to be half or less of the maximum depth of the second annular recess 10 from the larger diameter portion, the rigidity of the first annular recess is increased effectively. Thus, the folding in the second annular recess becomes still easier, and the folded state can be maintained more firmly. Brief Description of the Drawings 15 [00401 FIG 1 is a front view showing a first embodiment of a bottle according to the present invention, FIG 2 is a cross-sectional view of the periphery of an annular groove of the bottle shown in FIG 1. 20 FIG 3 is a view showing a state where a body has been contracted and deformed in the axial direction of a bottle axis to such a degree that an annular groove is crushed, from a state shown in FIG, 1. FIG, 4 is a front view showing a second embodiment of the bottle according to the present invention. 25 FIG 5 is a side view when the bottle shown in FIG 4 is seen from the direction 18 of an arrow A, FIG. 6 is a cross-sectional view as seen from the direction of an arrow B-B shown in FIG 4, FIG 7 is a view showing a state where a body has been contracted and deformed 5 in the axial direction of a bottle axis to such a degree that an annular groove is crushed, from the state shown in FIG 4. FIG 8 is a partial enlarged view of the bottle shown in FIG 4. FIG 9 is a front view showing a state before the filling of the bottle for heat filling according to the present invention. 10 FIG 10 is a front view showing the pressure-reduced absorbing state of this bottle. FIG 11 is an enlarged view of chief portions of a region X shown in FIG 9. FIG 12 is a cross-sectional view taken along a line A-A of FIG, 10, 15 Best Mode for Carrying out the Invention [0041] Hereinafter, a first embodiment of a bottle according to the present invention will be described with reference to FIGS. I to 3, In addition, in the present embodiment, description will be made taking a round bottle formed with a circular cross-section as an 20 example. As shown in FIG 1, the bottle I of the present embodiment is a bottomed tubular bottle I in which a mouth 2, a shoulder 3, a body 4, and a bottom 5 are integrally and continuously formed along a bottle axis L. Specifically, the bottle is integrally formed from synthetic resins, such as polyethylene terephthalate (PET), for example, by 25 biaxially-drawn blow molding.

19 [0042] The body 4 is a portion which is connected to an upper portion of the bottom 5 and formed in a tubular shape with the bottle axis L as a center. The body 4 will be described below in detail, The shoulder 3 is a portion which is connected so that its 5 diameter decreases gradually upward from an upper end of the body 4. The mouth 2 is a portion which is connected so as to extend upward from the upper end of the shoulder 3, and which becomes a spout when the contents (not shown) to be filled into the bottle 1 are poured out. In addition, the outer peripheral surface of the mouth 2 is formed with a threaded portion 2a on which a cap (not shown) is threadedly mounted. 10 [0043] As shown in FIGS. 1 and 2, the body 4 is formed with a circular cross-section wvith the bottle axis L as a center, The body 4 is formed with an annular groove 10 for contracting and deforming the body 4 along the axial direction of the bottle axis L when the internal pressure has been reduced, four annular ribs 11, 12, 13, and 14 which 15 increase the rigidity of the bottle I and supplementarily absorbs a pressure change at the time of pressure reduction, and one annular reinforcing rib 15 which increases the rigidity of the bottle 1. [0044] The annular groove 10 is a groove which is formed so as to be circumferentially 20 and radially recessed inward along the outer peripheral surface of the body 4 with the bottle axis L as a center on the upper side of the body 4 near the shoulder 3. Specifically, the annular groove 10 of the present embodiment is recessed and formed by a first wall surface I0a arranged on the mouth 2 side and a second wall surface 10b arranged on the bottom 5 side. The first wall surface 10a of the two wall surface 25 1 Ga and I Ob is a flat (planar) wall surface which extends radially inward from the outer 20 peripheral surface of the body 4. In more detail, the first wall surface 10a is a horizontal surface which extends so as to be orthogonal to the bottle axis L. On the other hand, the second wall surface I Ob is a wall surface which connects the first wall surface 10 a and the outer peripheral surface of the body 4 together, and is 5 formed in the shape of a curved surface which is smoothly curved toward the outer peripheral surface of the body 4 from the bottle axis (in the shape of a curved surface which is convex toward the inside of the bottle). Particularly, the second wall surface 10 b is adapted to gradually change in orientation so as to become parallel to the bottle axis L as it approaches the bottle axis which is connected to the first wall surface 10a. 10 [0045] Since the annular groove 10 is circumferentially recessed and formed in the body 4, the body 4 is adapted to be capable of being contracted and deformed in the axial direction of the bottle axis L with the annular groove 10 as a center when the internal pressure has been reduced. In this case, as shown in FIG. 3, the body is adapted to be 15 capable of being contracted and deformed to such a degree that the annular groove 10 is crushed, i.e., to such a degree that the first wall surface 10a and second w -all surface 1Ob approach to a position almost near abutment. [0046] Meanwhile, as shown in FIGS. I and 2, the body 4 is formed so that an outer 2.0 diameter 41 on the mouth 2 side and an outer diameter $2 on the bottom 5 side become different sizes with the annular groove 10 interposed therebetween. In detail, the body 4 is designed so that the outer diameter $4 on the bottom 5 side is larger than the outer diameter 41 on the mouth 2 side. Thereby, when the body is contracted and deformed to such a degree that the annular groove 10 is crushed, as shown in FIG. 3, the body 4 25 located on the mouth 2 side with the annular groove 10 as a boundary is brought into the 21 state of riding on and being supported by the body 4 located on the bottom 5 side so that the posture of the bottle is stabilized. This point will be described below in detail. [0047] The four annular ribs 11, 12, 13, and 14 are all grooves which are 5 circumferentially and radially recessed inward and formed along the outer peripheral surface of the body 4, and mainly play a role of increasing the rigidity of the whole bottle 1, thereby preventing the body 4 from being irregularly deformed (for example, deformation in an elliptical cross-sectional shape or a triangular cross-sectional shape) in the radial direction at the time of pressure reduction or from being deformed due to the 10 gripping force when the body 4 is gripped, the external force applied at the time of production and distribution, or the like. Additionally, in addition to this main purpose, the annular ribs 11, 12, 13, and 14 also play a supplementary role of contracting and deforming the bottle 1 in the axial direction and absorbing the remaining pressure change in a case where a pressure change 15 caused at the time of pressure reduction has not been absorbed enough by the annular groove 10. Therefore, the annular ribs 11, 12, 13, and 14 are recessed and formed so as be shallower than the annular groove 10. [0048] Particularly, two annular ribs 11 and 12 of the four annular ribs 11, 12, 13, and 20 14 are formed so as to be deeper than two remaining annular ribs 13 and 14. That is, the two annular ribs 11 and 12 are ribs which have a slightly higher importance for promoting axial contraction deformation than for increasing rigidity. On the other hand, contrary to this, the two remaining annular ribs 13 and 14 are ribs which have a slightly higher importance for increasing rigidity than for increasing axial contraction 25 deformation.

22 As such, two kinds of annular ribs 11, 12, 13, and 14 which have slightly different roles are arranged alternately from the bottom 5 side. [0049] In addition, in the present embodiment, the annular rib 11 is first arranged on the 5 bottom 5 side. Contrary to this, however, the annular rib 13 may be arranged first. Additionally, the annular ribs may not be arranged alternately, and the balance of an arrangement may be appropriately changed according to the size, shape, or the like of the bottle 1. Additionally, the annular ribs are lot limited to the four annular ribs, and the number of the annular ribs may be changed appropriately. 10 [0050] The annular reinforcing rib 15 is circumferentially and radially recessed inward and formed along the outer peripheral surface of the body 4 at a position nearer the shoulder 3 than the annular groove 10, The annular reinforcing rib 15 has a role of preventing the body 4 from being irregularly deformed in the radial direction at the time 15 of pressure reduction or from being deformed due to the gripping force when the body 4 is gripped. Hence, the annular reinforcing rib 15 is recessed and formed so as to be shallower than the annular groove 10, and is designed so that the body 4 is not contracted and deformed in the axial direction substantially with the annular reinforcing rib 15 as a center. 20 [0051] Next, a case where the internal pressure of the bottle 1 constructed in this way has been reduced for the reasons of cooling or the like after heating and filling of the contents thereof will be described below. In a case where the internal pressure has been reduced, the pressure which will 25 contract the bottle in the axial direction of the bottle axis L mainly acts on the whole 23 bottle 1. In this case, since the annular groove 10 is circumferentially recessed and formed in the body 4, the body 4 is contracted and deformed in the axial direction with the annular groove 10 as a center. Thereby, the above pressure change at the time of pressure reduction can be absorbed by the axial contraction of the bottle 1. 5 [0052] Meanwhile, the body 4 of the bottle 1 is designed so that the outer diameter 42 on the bottom 5 side is larger than the outer diameter $1 on the mouth 2 side. Therefore, as shown in FIG 3, when the body 4 has been contracted in the axial direction to such a degree that the annular groove 10 is crushed by pressure reduction, the body 4 located on 10 the mouth 2 side is brought into the state of riding on and being supported by the body 4 on the bottom 5 side, and consequently the posture of the bottle is stabilized. Particularly, since the body 4 on the mouth 2 side is not partially supported but supported over its entire circumference by the body 4 on the bottom 5 side, the posture of the bottle is remarkably stable. 15 Accordingly, even if the contraction deformation by the annular groove 10 occurs, irregular deformation, such as bending of the neck where the mouth 2 side of the body 4 bends, hardly occurs. Hence, occurrence of appearance degradation can be suppressed. [0053] 20 As described above, according to the bottle 1 of the present embodiment, by contracting and deforming the body 4 in the axial direction, not only the pressure change which has occurred at the time of pressure reduction can be absorbed but also occurrence of irregular deformation, such as bending of the neck in this contraction deformation, can be suppressed. 25 Moreover, in the bottle 11 of the present embodiment, the body 4 is provided 24 with the four annular ribs 11, 12, 13, and 14 separately from the annular groove 10. Thus, the pressure change which could not be absorbed by the annular groove 10 can be absorbed by the contraction deformation with the four annular ribs 11, 12, 13, and 14 as centers. Moreover, since the whole rigidity is increased by the four annular ribs 11, 12, 5 13, and 14 and one annular reinforcing rib 15, irregular deformation of the body 4 hardly occur at the time of pressure reduction, and the radial rigidity, for example, when the bottle 1 is gripped, is also excellent. In addition, since the bottle 1 is a bottle of an unpanelled type in which the body 4 is not provided with a general pressure-reduction absorption panel, the design thereof 10 can be comparatively freely performed without being restricted by the pressure-reduction absorption panel. Hence, the degree of design freedom can be improved. [0054] Additionally, the bottle I of the present embodiment can exhibit the following working effects in addition to the above-described working effects. 15 That is, the second wall surface 1 Ob located on the bottom 5 side among the two wall surfaces which constitutes the annular groove 10 is formed in the shape of a curved surface which is curved toward the outer peripheral surface of the body 4 from the bottle axis, and gradually changes in orientation so as to become parallel to the bottle axis 1 as it approaches the bottle axis connected to the first wall surface 10a, Accordingly, when 20 the internal pressure is reduced, the body 4 on the mouth 2 side can be easily pulled downward, and axial contraction deformation can be made to occur easily. Typically, in a case where contraction deformation is made in the axial direction, it is natural that the body 4 on the mouth 2 side moves downward. In this regard, since the body 4 on the mouth 2 side is easily pulled downward by the second wall surface lOb, contraction 25 deformation can be made to occur easily in a nearly natural form. Accordingly, a 25 pressure change at the time of pressure reduction can be absorbed more effectively. [0055] Moreover, since the first wall surface I 0a is a horizontal surface orthogonal to the bottle axis L, a surface parallel to the bottle axis L does not exist. Therefore, the 5 body 4 on the mouth 2 side can be more positively pulled downward by the second wall surface lOb, and the pressure change at the time of pressure reduction can be absorbed still more effectively. In addition, since the first wall surface 10a is the horizontal surface, the body 4 on the mouth 2 side rides easily on the body 4 on the bottom 5 side in a more stable state, 10 Accordingly, irregular deformation, such as bending of the neck, can be suppressed more effectively. [0056] In addition, the technical scope of the invention is not limited to the above embodiment, but various modifications may be made without departing from the scope of 15 the invention. [00571 For example, in the above embodiment, the bottle I is integrally formed by the biaxially-drawn blow molding from synthetic resins, such as PET, the manufacturing method is not limited thereto, Additionally, although description has been made taking 20 the bottle I in which the body 4 has a circular cross-sectional shape as an example, the body 4 may be an angled bottle formed in an angled shape. [0058] Additionally, in the above embodiment, the first wall surface 10 a is a horizontal surface orthogonal to the bottle axis L. However, a flat surface which inclines to the 25 bottle axis . may be adopted. Moreover, the first wall surface may be a wall surface 26 formed in the shape of a curved surface similarly to the second wall surface lOb. It is noted herein that the horizontal surface is preferably adopted as the first wall surface. Additionally, the first wall surface 10 a and second wall surface I Ob may be connected together via a connecting wall. In this case, the cross-sectional shape of the 5 annular groove 10 becomes a substantially trapezoidal shape, and the connecting wall can be appropriately set to a planar shape (which is parallel to or inclined with respect to the bottle axis L) or the shape of a curved surface according to the degree of deformation intended. [0059] 10 Hereinafter, a second embodiment of the bottle according to the present invention will be described with reference to FIGS. 4 to 8. In addition, in the present embodiment, description will be made taking a round bottle formed with a circular cross-section as an example, In addition, the same elements as those of the above embodiment will be designated by the same reference numerals, and a description thereof 15 will be omitted. [0060] In the present embodiment, as shown in FIGS. 4 to 6, the body 4 is formed with a circular cross-section with the bottle axis L as a center. The body 4 is formed with an annular groove 20 for contracting and deforming the body 4 along the axial direction of 20 the bottle axis L, when the internal pressure is reduced, and an annular reinforcing rib 21 for reinforcement. The annular groove 20 is a V-shaped groove which is formed so as to be circumferentially and radially recessed inward along the outer peripheral surface of the body 4 with the bottle axis L as a center on the upper side of the body 4 near the mouth 2, 25 Specifically, the annular groove 20 of the present embodiment is constituted by an upper 27 inclined surface (mouth-side inclined surface) 20a and a lower inclined surfaces (bottom-side inclined surface) 20b which are two wall surfaces which face each other. Both the inclined surfaces 20a and 20b are wall surfaces which face each other so as to incline in directions opposite to each other with respect to the bottle axis L. That is, the 5 upper inclined surface 20a is an inclined surface which faces the bottom 5 side and the lower inclined surface 20b is an inclined surface which faces the mouth 2 side. [0061] Since the annular groove 20 is circunferentially recessed and formed in the body 4, the body 4 is adapted to be capable of being contracted and deformed in the axial 10 direction of the bottle axis L with the annular groove 20 as a center when the internal pressure is reduced. In this case, as shown in FIG. 7, the body is adapted to be capable of being contracted and deformed to such a degree that the upper inclined surface 20a and the lower inclined surface 20b approach a position almost near abutment. [0062] 15 In addition, as shown in FIG 6, the depth of the annular groove 20 is adjusted so that the outer diameter 5 1 has a size of about 80% with respect to the outer diameter #)2 of the body 4. Since appropriate depth adjustment is made in this way, it is designed so that the body 4 is smoothly contracted and deformed with the annular groove 20 as a center as described above. 20 [0063] In the present embodiment, as shown in FIGS. 4 and 5, three annular reinforcing ribs 21 are formed. One reinforcing rib is formed on the lower side of the body 4 near the bottom S, and the two remaining reinforcing ribs are formed so as to interpose the annular groove 20 therebetween, The annular reinforcing ribs 21 are all grooves which 25 are circurnferentially and radially recessed inward and formed along the outer peripheral 28 surface of the body 4, and play a supplementary role of preventing the body 4 from being irregularly deformed (for example, defonnation in an elliptical cross-sectional shape or a triangular cross-sectional shape) in the radial direction at the time of pressure reduction. Additionally, the annular reinforcing ribs also play a role of preventing the body 4 from 5 being irregularly deformed by a gripping force when the body 4 is gripped. In addition, the annular reinforcing ribs 21 are recessed and formed so as to be shallower than the above-described annular groove 20. 'Therefore, the body 4 is designed so as not to be contracted and deformed in the axial direction of the bottle axis L substantially with the annular reinforcing rib 21 as a center. 10 [0064] Meanwhile, as shown in FIGS. 4 to 6 and 8, a plurality of protrusions 25 is formed on the lower inclined surface 20b which is one inclined surface of the upper inclined surface 20a and the lower inclined surface 20b which constitute the annular groove 20, Specifically, six protrusions are formed at regular intervals (at every 60 15 degrees with the bottle axis L as a center) in the circumferential direction. Moreover, the respective protrusions 25 are forced so as to enter closer to the annular groove 20 side than a boundary line (connecting corner) S between the lower inclined surface 20b and the outer peripheral surface of the body 4, and are brought into the state of being completely stored in the lower inclined surface 20b. 20 [0065] Here, the protrusions 25 of the present embodiment will be described in more detail with reference to FIG. 8. The protrusions 25 are formed in the shape of a triangle which has a ridgeline R when the lower inclined surface 20b is seen in plane view. In this case, the ridgeline R is designed so as to extend toward the outer peripheral surface 25 of the body 4 while being orthogonal to the circumferential direction of the lower 29 inclined surface 20b when the lower inclined surface 20b is seen in plane view. That is, the ridgeline R is designed so as to extend radially outward when the body 4 is seen from the axial direction of the bottle axis L. Also, the protrusions 25 are formed in the shape of a triangle of which one side overlaps a valley line T of the annular groove 20 and 5 which protrudes while narrowing gradually toward the above-described boundary line S along the ridgeline R., [0066] On the other hand, recesses 26 which accommodate the protrusions 25, respectively, when both the inclined surfaces 20a and 20b approach each other are 10 formed at positions which face the protrusions 25, on the upper inclined surface (other inclined surface) 20a which is an inclined surface on the side opposite to the lower inclined surface 20b on which the protrusions 25 are formed. That is, the recesses 26 are formed at the same regular intervals (every 60 degrees) as the protrusions 25 in the circumferential direction in the upper inclined surface 20a. Additionally, the respective 15 recesses 26, similarly to the protrusions 25, are also formed so as to enter closer to the annular groove 20 side than a boundary line S between the upper inclined surface 20a and the outer peripheral surface of the body 4, and are brought into the state of being completely stored in the upper inclined surface 20a. [0067] 20 Next, a case where the internal pressure of the bottle 50 constructed in this way has been reduced for the reasons of cooling or the like after heating and filling of contents will be described below. In a case where the internal pressure is reduced, the pressure which will contract the bottle in the axial direction of the bottle axis L and the pressure which will contract 25 the bottle in the radial direction act on the whole bottle 50. In this case, since the 30 annular groove 20 is circunferentially recessed and formed in the body 4, the body 4 is contracted and deformed in the axial direction with the annular groove 20 as a center. Thereby, the aforementioned pressure change at the time of pressure reduction can be absorbed. Moreover, since the annular groove 20 is formed in the shape of the letter V 5 by the upper inclined surface 20a and the lower inclined surface 20b, the body 4 is easily contracted and deformed in the axial direction with the annular groove 20 interposed therebetween. Hence, the above pressure change can be inunediately absorbed with an immediate reaction. [0068] 10 On the other hand, since the bottle 50 simultaneously receives the pressure which will contract the bottle in the radial direction independently from the pressure which will contract the bottle in the axial direction, the force pulling radially inward also acts on the portion of the annular groove 20. However, since the protrusions 25 are formed on the lower inclined surface 20b which constitutes the annular groove 20, it is 15 considered that the body 4 can suppress such deformation in which folded wrinkles are created due to the elastic deformation with the protrusions 25 as base points. Particularly, since the protrusions 25 have the ridgeline R, the protrusions are easily deformed with the ridgeline R as a base point. Accordingly, it is considered that the above-described elastic deformation is easily induced in the body 4. 20 [0069] From the foregoing, an internal pressure change caused at the time of pressure reduction can be reliably absorbed in the axial contraction of the bottle axis L while suppressing such plastic deformation in which folded wrinkles may be created in the annular groove 20, 25 Moreover, since the bottle 50 of the present embodiment has three annular 31 reinforcing ribs 21 irregular deformation of the body 4 hardly occur at the time of pressure reduction, the radial rigidity, for example, when the bottle 50 is gripped, is also excellent. Additionally, since the bottle 50 is a bottle of a unpanelled type in which the body 4 is not provided with a general pressure-reduction absorption panel, design thereof 5 can be comparatively freely performed without being restricted by the pressure-reduction absorption panel. Hence, the degree of design freedom can be improved. [00701 Additionally, the bottle 50 of the present embodiment can exhibit the following working effects in addition to the above-described working effects. 10 First, since a plurality of protrusions 25 is formed, creation of folded wrinkles can be effectively suppressed in all the regions in the circumferential direction. That is, since the elastic deformation with the protrusions 25 as base points occurs equally in the circumferential direction of the body 4, it is considered that the possibility of folded wrinkles being created in the annular groove 20 can be further reduced. 15 [00711 Additionally, since the recesses 26 are formed in the upper inclined surface 20a which constitutes the annular groove 20, even if the body 4 is contracted and deformed to such a degree that the annular groove 20 is crushed in the axial direction of the bottle axis L, as shown in FIG 7, the protrusions 25 can be prevented from Interfering with the 20 upper inclined surface 20a, When the internal pressure is reduced, as described above, the body 4 is contracted and deformed in the axial direction with the annular groove 20 as a center, thereby absorbing a pressure change within the bottle 50. However, in a case where this pressure change is comparatively large, the body 4 is contracted and deformed to such a 25 degree that the annular groove 20 is completely crushed (the upper inclined surface 20a 32 and the lower inclined surface 20b abut on each other). In this case, there is a probability that the protrusions 25 may interfere with the upper inclined surface 20a, and thus contraction deformation of the body 4 may be hindered, or folded wrinkles may be created in the upper inclined surface 25a by the protrusions 25, 5 However, since the recesses 26 in which the protrusions 25 are accommodated are formed in the upper inclined surface 20a, the probability that the protrusions 25 may interfere with the upper inclined surface 20a and hinder contraction deformation of the body 4 can be eliminated. [0072] 10 Moreover, the protrusions 25 are formed in a state where the protrusions are completely stored in the lower inclined surface 20b, and are designed so that portions of the protrusion 25 are not exposed to the outer peripheral surface side of the body 4 beyond the boundary line S between the lower inclined surface 20b and the outer peripheral surface of the body 4. Accordingly, a probability that the protrusions 25 may 15 abut on the boundary line S, and folded wrinkles may be created in the outer surface of the bottle can be prevented in advance. [0073] In addition, the technical scope of the invention is not limited to the above embodiment, but various modifications may be made without departing from the scope of 20 the invention. [0074] For example, in the above embodiment, the bottle is integrally formed by the biaxially-drawn blow molding from synthetic resins, such as PET, the manufacturing method is not limited thereto. Additionally, although a description has been made 25 taking the bottle in which the body 4 has a circular cross-sectional shape as an example, 33 the body 4 may be an angled bottle formed in an angled shape. [0075]1 Additionally, although description has been made in the above embodiment taking the case where only one annular groove 20 is formed as an example, two or more 5 annular grooves may be formed. Even in this case, the same working effects can be exhibited. Additionally, although three annular reinforcing ribs 21 are formed, the formation position and number thereof may be designed freely, Appropriate changes may be made to the annular grooves 20 and the annular reinforcing rib 21 according to the size, shape, and the like of a bottle. 10 [0076] Additionally, in the above embodiment, the protrusions 25 are formed on the lower inclined surface 20b which constitutes the annular groove 20 and the recesses 26 are formed in the upper inclined surface 20a. Contrary to this, however, the protrusions 25 may be formed on the upper inclined surface 20a and the recesses 26 may be formed 15 in the lower inclined surface 20b. Even in this case, the same working effects can be exhibited. Moreover, the protrusions 25 and the recesses 26 may be formed in both the upper inclined surface 20a and the lower inclined surface 20b, respectively. For example, the protrusions 25 and the recesses 26 may be formed in both the upper inclined surface 20a and the lower inclined surface 20b so as to be lined up alternately in the 20 circumferential direction. Even in this case, the same working effects can be exhibited, Moreover, although the case, where both the two wall surfaces that constitute the annular groove 20 are constructed by inclined surfaces (the upper inclined surface 20a, the lower inclined surface 20b), is exemplified in the above embodiment, one of the wall surfaces may be constructed as a horizontal surface. 25 [0077] 34 Moreover, although six protrusions 25 and six recesses 26 are formed at regular intervals in the circumferential direction, the number of the protrusions and recesses is not limited to this and may be set freely. Even if not a plurality of protrusions 25 and a plurality of recesses 26, but only one protrusion and only one recess is formed, the same 5 working effects can be expected. It is noted herein that it is preferable that a plurality of (preferably three or more) protrusions 25 be formed and arranged at equal intervals in that a pressure change is absorbed more reliably. Additionally, in a case where a plurality of protrusions 25 is formed, the protrusions may not be arranged at regular intervals. It is noted herein that, since a pressure change can be equally absorbed in a 10 well-balanced manner, it is preferable to arrange the protrusions 25 equally in the circumferential direction at regular intervals, [0078] Hereinafter, a third embodiment of a bottle according to the present invention will be described with reference to FIGS. 9 to 12. In addition, the same elements as 15 those of the above embodiments will be designated by the same reference numerals, and a description thereof will be omitted. [0079] FIGS. 9 and 10 are respectively a font view showing a state before filling of the bottle 30 for heat filling (hereinafter referred to as "bottle") according to the invention 20 and a front view showing the pressure-reduced absorbing state of the bottle 30. Additionally, FIG. 11 is an enlarged view of chief portions of a region X shown in FIG, 9, and FIG, 12 is a cross-sectional view taken along the line A-A of FIG 10, [00801 The bottle 30 is a biaxially-drawn blow molding bottle obtained by integrally 25 molding a mouth 31, a cylindrical neck tube 32 connected via a neck ring 31 a provided at 35 the mouth 31, a shoulder 33 which is enlarged in diameter integrally from the neck tube 32, a body 34 connected to the shoulder 33, and a bottom 36 connected to the body 34 via a heel 35 and having polyethylene terephthalate (PET) as a principal component. [0081] 5 The body 34 is formed with a larger diameter portion 34a which is formed as a tubular portion of diameter 034a by making the diameter of an upper portion 34a of the body 34 larger than the diameter of a lower portion 34b radially outward, and a smaller diameter portion 34b which is formed as a tubular portion of diameter $34b which has a smaller diameter than the larger diameter portion 34a. 10 [00821 The larger diameter portion 34a is formed with a first annular recess (hereinafter referred to as a "first annular recess") 41 which is formed by recessing a portion of the larger diameter portion radially inward along the circumference of an axis 0, 10083] 15 As showny in FIG 11, a maximum inner diameter portion 41 a of the first annular recess 41 forms an annular flat surface, and the maximum inner diameter portion 41a is connected to an upper portion (hereinafter, a "larger diameter upper portion") 34ai and a lower portion (hereinafter, a "larger diameter lower portion") 34az of a larger diameter portion split by the first annular recess 41. 20 [0084] In this case, as shown in FIG 11, an annular connecting portion 41b which connects together the larger diameter upper portion 34a, and the maximum inner diameter portion 4 1 a is formed as an annular curved surface which swells toward the outside of the bottle 30. However, the annular connecting portion 41b may be an 25 annular curved surface which swells toward the inside of the bottle 30, an annular flat 36 surface which extends while inclining radially outward toward the larger diameter upper portion 34ai, or an annular flat surface which horizontally extends radially outward toward the larger diameter upper portion 3 4aj, [0085] Additionally, as shown in FIG 11, an annular connecting portion 41 c which connects together the larger diameter lower portion 34a2 and the maximum inner diameter portion 41 a is formed as an annular curved surface which swells toward the outside of the bottle 30. However, the annular connecting portion 41c may be an annular curved surface which swells toward the inside of the bottle 30, an annular flat 10 surface which extends while inclining radially outward toward the larger diameter lower portion 34a2, or an annular flat surface which horizontally extends radially outward toward the larger diameter lower portion 34a2. [0086] Additionally, the first annular recess 41 may be constructed as an annular curved 15 surface which connects together the larger diameter upper portion 34ai and the larger diameter lower portion 34a2 which are split by the first annular recess 41, and the inflection point thereof may be the maximum inner diameter portion 41a. That is, as the first annular recess 41, various cross-sectional shapes can be employed as long as the cross-sectional shapes can exhibit high strength (high rigidity at which deformation 20 hardly occurs) against buckling, [0087] On the other hand, reference numeral 42 designates a second annular recess (hereinafter referred to as a "second annular recess") which is formed by recessing a portion of the smaller diameter portion 34b radially inward along the circumference of 25 the axis 0 so as to come into contact with the larger diameter lower portion 34a2.

37 (0088] The second annular recess 42 has an annular upper surface (hereinafter referred to as a "second annular recess upper surface") 42a which is connected to the larger diameter lower portion 34az, and an annular lower surface (hereinafter referred to as a 5 "second annular recess lower surface") 42b which is connected to the smaller diameter portion 34b. These annular upper and lower surfaces are connected together by the maximum inner diameter portion 42c which is formed as a curved surface. In addition, according to the invention, the maximum inner diameter portion 42c may be an annular flat surface as long as the second annular recess upper surface 42a can be folded toward 10 the second annular recess lower surface 42b. [0089] Additionally, the second annular recess upper surface 42a may be adapted such that deformation hardly occurs when being folded toward the second annular recess lower surface 42b. In the present embodiment, as shown in FIG 11, the larger diameter 15 lower portion 34a2 and the maximum inner diameter portion 42c are connected together as an annular curved surface which swells toward the outside of the bottle 30 with the radius of curvature ri. In this regard, according to the invention, an annular curved surface which swells toward the inside of the bottle 30, a flat surface which horizontally extends radially outward toward the larger diameter lower portion 34a2 or extends while 20 inclining radially outward, or the like may be adopted as the second annular recess upper surface 42a. [0090] Additionally, in combination with this, in the present embodiment, the portion 34a2(e) of the larger diameter lower portion 34a2 which comes into contact with the 25 second annular recess ipper surface 42a is also constructed as an annular curved surface 38 which swells toward the outside of the bottle 30 with the radius of curvature r2. In this regard, according to the invention, the portion 34a2(e) which comes into contact with the second annular recess upper surface 42a may be constructed as an annular curved surface which swells toward the inside of the bottle 30 with the radius of curvature r2, a flat 5 surface which horizontally extends radially outward toward the larger diameter lower portion 34a2 or extends while inclining radially outward, or the like. [0091] The second annular recess lower surface 42b may be adapted such that deformation hardly occurs when the second annular recess upper surface 42a is folded. 10 In the present embodiment, as shown in FIG 11, the smaller diameter lower portion 34b and the maximum inner diameter portion 42c are connected together as an annular flat surface which extends while inclining radially outward toward the smaller diameter portion 34b, In this regard, according to the present embodiment, an amular flat surface which horizontally extends radially outward toward the smaller diameter portion 15 34b, or an annular curved surface which swells toward the outside or inside of the bottle 30 can also be adopted as the second annular recess lower surface 42b, [0092] Additionally, in combination with this, in the present embodiment, the portion 34b(e) of the smaller diameter portion 34b which comes into contact with the second 20 annular recess lower surface 42b is also constructed as a curved surface which swells toward the outside of the bottle 30. [0093] Moreover, the second annular recess 42 may be formed in the smaller diameter portion 34b so as to come into contact with the larger diameter portion 34a. In this case, 25 the second annular recess upper surface 42a may be connected to the larger diameter 39 portion 34a so that the outermost diameter $42a thereof becomes equal to the outer diameter $34b of the smaller diameter portion 34b. However, in the present embodiment, the second annular recess upper surface 42a is adapted so that a deviation AC. is caused radially outward with respect to the second annular recess lower surface 5 42b by making the outermost diameter $42a longer than the outermost diameter $42b of the second annular recess lower surface 42b and a deviation AC 2 is caused radially inward with respect to the smaller diameter portion 34b by making the outermost diameter $42a shorter than the outer diameter $34b of the smaller diameter portion 34b. [0094] 10 That is, as cross-sectional shapes of the second annular recess 42, various cross-sectional shapes (in which deformation hardly occurs) can be adopted as long as the second annular recess upper surface 42a which is connected to the larger diameter lower portion 34a2 is easily folded toward the second annular recess lower surface 42b which is connected to the smaller diameter portion 34b. 15 [0095] In addition, in the present embodiment, the maximum depth D2 of the second annular recess 42 from the larger diameter portion 34a is set to be larger than the maximum depth D1 of the first annular portion 41 from the larger diameter portion 34a

(D

2

>D

1 ). Additionally, the maximum depth D2 is made equal to or smaller than the 20 axial dimension La between the first annular recess 41 and the second annular recess 42 (D2<Lu). Thereby, the second annular recess upper surface 42a is more easily folded toward the second annular recess lower surface 42b. [0096] In the present invention, the upper portion and the lower portion of the body 34 40 are formed as the larger diameter portion 34a and the smaller diameter portion 34b, respectively, the first annular recess 41 is formed by recessing a portion of the larger diameter portion 34a radially inward along the circumference of the axis 0, the second annular recess 42 is formed by recessing a portion of the smaller diameter portion 34b 5 radially inward along the circumference of the axis 0 so as to come into contact with the larger diameter portion 34a. Furthermore, the second annular recess upper surface 42a is made foldable toward the second annular recess lower surface 42b by making the maximum depth D 2 of the second annular recess 42 from the larger diameter portion 34a larger than the maximum depth D, of the first annular recess 41 from the larger diameter 10 portion 34a and equal to or smaller than the axial dimension L1 between the first annular recess 41 and the second annular recess 42, Therefore, the second annular recess upper surface 42a is easily folded toward the second annular recess lower surface 42b over its entire circumference. For this reason, as the internal pressure of the bottle 30 is reduced or an external force is applied to the bottle 30 in the direction of the axis 0, the bottle 30 15 can be easily compressed and deformed with respect to the direction of the axis O. [0097] Moreover, according to the embodiment of the present invention, even after the second annular recess upper surface 42a is folded toward the second annular recess lower surface 42b, the folded state can be maintained. Since the folded state is not related to 20 whether or not the bottle 30 is in a pressure-reduced state, contents can also be filled in a state where the bottle 30 is folded and compressed in advance. [0098] Accordingly, in the bottle 30 according to the embodiment of the present invention, the body 34 is equally folded in the direction of the axis 0 and the folded state 25 is maintained even if the internal pressure of the bottle 30 is reduced, Therefore, it is 41 possible to provide a bottle which has an aesthetic outward appearance and is beautiful to markets or the like. [0099] In addition, it is considered that the reason why the folding in the second annular 5 recess 42 becomes easy is because the rigidity in the first annular recess 41 formed above the second annular recess 42 is high and the first annular recess 41 functions as a rib A which is bendable without buckling, and thereby, the larger diameter lower portion 34a2 spreads radially outward as a rib B which is not deformable, and the second annular recess 42 functions as a rib C which easily bends radially inward. On the other hand, it 10 is considered that the reason why the folded state in the second annular recess 42 is maintained is because the first annular recess 41 serving as the rib A with high rigidity prevents its restoration if the larger diameter lower portion 34a2 serving as the rib B spreads radially outward and the second annular recess 42 serving as the rib C is once bent. 15 [0100] For this reason, in the present embodiment of the present invention, if the maximum depth Dl of the first annular recess 41 from the larger diameter portion 34a is set to be equal to or smaller than half (D D2/2) of the maximum depth D 2 of the second annular recess 42 from the larger diameter portion 34a, the rigidity of the first annular 20 recess 41 is increased effectively. Thus, the folding in the second annular recess 42 becomes still easier, and the folded state can be maintained more firmly. [0101] In addition, in the present embodiment, the axial dimension of the first annular recess 41 is set to be shorter than the axial dimension of the second annular recess 42, 25 Additionally, the respective axial dimensions L 1 1 a, L41, and L 4 10 of the naximun inner 42 diameter portion 41a and connecting portions 41b and 41c of the first annular recess 41 have the relationship of 2:1:1, and the respective axial dimensions L 4 2 . L42b, and L42 of the upper surface 42a, lower surface 42b, and maximum inner diameter portion 42c of the second annular recess 42 have the relationship of 1:1:1 Moreover, the radii of 5 curvature ri, r2, and r3 have the relationship of r>r3r2. [0102] Although preferred embodiments of the invention have been described above, various changes can be made in the claims. For example, although the bottle 30 is a cylindrical bottle, a prismatic bottle or the like can also be adopted, Additionally, 10 although the invention is mainly adopted as one having a heat-filled bottle as a main body, the invention is not limited thereto. Industrial Applicability [0103] 15 According to the bottle related to the embodiment of the present invention, a pressure change caused at the time of pressure reduction can be absorbed by axial contraction deformation. In addition to this, since the body on the mouth side is stably supported by the body on the bottom side even in a case where contraction deformation has occurred to such a degree that the annular groove is crushed, irregular deformation, 20 such as bending of the neck, can be suppressed. Additionally, according to the bottle related to the embodiment of the present invention, the bottle can be contracted and deformed in the axial direction while suppressing creation of folded wrinkles at the time of pressure reduction, and a pressure change caused at the time of pressure reduction can be absorbed reliably. 25 Additionally, according to the bottle related to the embodiment of the present 43 invention, the body of the bottle is equally folded in the direction of the axis and the folded state is maintained even if the internal pressure of the bottle is reduced. Therefore, it is possible to provide to the market or the like a bottle which has an aesthetic outward appearance and is beautiful, 5 Reference Signs List [0104] L: BOTTLE AXIS $1: OUTER DIAMETER OF BODY ON MOUTH SIDE 10 62: OUTER DIAMETER OF BODY ON BOTTOM SIDE 1: BOTTLE 2: MOUTH 3: SHOULDER 4: BODY 15 5: BOTTOM 10: ANNULAR GROOVE 10a: FIRST WALL SURFACE 10b: SECOND WALL SURFACE R: RIDGELINE OF PROTRUSION 20 20: ANNULAR GROOVE 20a: UPPER INCLINED SURFACE (WALL SURFACE) OF ANNULAR GROOVE 20b: LOWER INCLINED SURFACE (WALL SURFACE) OF ANNULAR GROOVE 25 25: PROTRUSION 44 26: RECESS 30: HEAT-FILLED BOTTLE (BOTTLE) 31: MOUTH 31a: NECK RING 5 32: NECK TUBE 33: SHOULDER 34: BODY 34a: BODY UPPER PORTION (LARGER DIAMETER PORTION) 34a,: LARGER DIAMETER. UPPER PORTION (UPPER PORTION OF 10 LARGER DIAMETER PORTION) 34a2: LARGER DIAMETER LOWER PORTION (LOWER PORTION OF LARGER DIAMETER PORTION) 34az(e): PORTION OF LARGER DIAMETER LOWER PORTION WHICH COMES INTO CONTACT WITH SECOND ANNULAR RECESS 2 15 34b: BODY LOWER PORTION (SMALLER DIAMETER PORTION) 34b(e): PORTION OF SMALLER DIAMETER PORTION WHICH COMES INTO CONTACT WITH LOWER SURFACE OF SECOND ANNULAR RECESS 35: HEEL 36: BOTTOM 20 41: FIRST ANNULAR SURFACE 41 a: MAXIMUM INNER DIAMETER PORTION OF FIRST ANNULAR RECESS 41b: ANNULAR CONNECTING PORTION WHICH CONNECTS TOGETHER LARGER DIAMETER UPPER PORTION AND MAXIMUM INNER 25 DIAMETER PORTION 45 41c: ANNULAR CONNECTING PORTION WHICH CONNECTS TOGETHER LARGER DIAMETER LOWER PORTION AND MAXIMUM INNER DIAMETER PORTION 42: SECOND ANNULAR RECESS 5 42a: SECOND ANNULAR RECESS UPPER SURFACE (UPPER SURFACE OF SECOND ANNULAR RECESS CONNECTED TO LARGER DIAMETER LOWER PORTION) 42b: SECOND ANNULAR RECESS LOWER SURFACE (LOWER SURFACE OF SECOND ANNULAR RECESS CONNECTED TO SMALLER 10 DIAMETER PORTION) 42c: MAXIMUM INNER DIAMETER PORTION OF SECOND ANNULAR RECESS A: RIB (FIRST ANNULAR RECESS) B: RIB (LARGER DIAMETER LOWER PORTION) 15 C: RIB (SECOND ANNULAR RECESS) DI: MAXIMUM DEPTH OF FIRST ANNULAR PORTION

D

2 : MAXIMUM DEPTH FROM LARGER DIAMETER PORTION IN SECOND ANNULAR. RECESS L: AXIAL DIMENSION BETWEEN FIRST ANNULAR RECESS AND 20 SECOND ANNULAR RECESS ri: RADIUS OF CURVATURE ON SECOND ANNULAR RECESS UPPER SURFACE r2 RADIUS OF CURVATURE OF THE PORTION OF LARGER DIAMETER LOWER PORTION WHICH COMES INTO CONTACT WITH SECOND 25 ANNULAR RECESS UPPER SURFACE 46 r3: RADIUS OF CURVATURE OF THE PORTION OF SMALLER DIAMETER PORTION WHICH COMES INTO CONTACT WITH SECOND ANNULAR RECESS LOWER SURFACE

Claims (5)

1.. A bottomed tubular bottle comprising: an annular groove which is formed so as to be circumferentially and radially recessed inward along the outer peripheral surface of a body ofthe bottle with the bottle axis as a center and which contracts and deforms the body in the axial direction of the bottle axis when the internal pressure is reduced, wherein the annular groove is formed in the shape of the letter V by two facing wall surfaces, a protrusion is formed on at least one wall surface of the wall surfaces, and the protrusion has a ridgeline which extends toward the outer peripheral surface of the body while being orthogonal to the circumferential direction ofthe wall surface when the wall surface on which the protrusion is formed is seen in plane view.

2 The bottle according to Claim 1, wherein a plurality of the protrusions is formed at regular intervals in the circumferential direction.

3. The bottle according to Claim I or 2, wherein the protrusion is formed so as to enter closer to the annular groove side than the outer peripheral surface of the body. 48

4, The bottle according to Claim 1, wherein a recess which accommodates the protrusion is formed at a position which faces the protrusion on at least the other wail surface of the two wail surfaces when both the wall surfaces approach each other in the axial direction of the bottle axis.

5. The bottle according to Claim 4, wherein the recess is formed so as to enter closer to the annular groove side than the outer peripheral surface of the bodv.