JP5966358B2 - Plastic container - Google Patents

Description

  The present invention relates to a rectangular bottle-shaped synthetic resin container having a high resilience against a shape change.

  Conventionally, a synthetic resin container formed by forming a bottomed cylindrical preform using a thermoplastic resin such as polyethylene terephthalate, and then molding the preform into a bottle shape by biaxial stretch blow molding or the like, It is generally used in a wide field as a beverage container containing various beverage products.

  In recent years, such synthetic resin containers have been rapidly and widely spread, and accordingly, it is strongly demanded to make the containers thinner. In particular, for those used for relatively large capacity applications, the weight of the container accompanying the increase in size has become a problem, and the cost disadvantage caused by the amount of material resin used. Improvements are also required for resource conservation as environmental measures.

  In addition, when filling the contents of this type of synthetic resin container, it is known that the contents are sterilized at a high temperature and then filled (hot-packed) in order to suppress the growth of bacteria after filling. In this case, when the container is cooled after being filled and sealed, the inside of the container is decompressed. For this reason, the side surface of the body part of the container used for the hot pack is usually provided with a vacuum absorption panel for adjusting the rigidity of the container to uniformly deform the body side surface, thereby reducing the internal pressure. This prevents the non-uniform shape change of the container.

  However, if the container is made thin, the weight of the contents increases, and the lower part of the container body tends to swell, and the rigidity of the container can withstand the weight of the contents. If it is going to raise, the deformation | transformation of the container for absorbing pressure reduction will be suppressed, and there exists a problem that pressure reduction absorption performance falls.

  On the other hand, since the upper part of the container body is relatively less affected by the weight of the contents, a panel shape with high vacuum absorption performance is adopted on the upper side of the container body, thereby increasing the vacuum absorption. In general, however, the rigidity of the container and the vacuum absorption performance are in a trade-off relationship. For this reason, in order to compensate for the lowering of the vacuum absorption performance on the lower side of the container body, if a panel shape having a high vacuum absorption performance is adopted on the upper side of the container body to increase the vacuum absorption, Becomes relatively low, and there arises a problem that the container is easily dented by an external force. Thus, when actually designing the container shape, these balances must be taken into consideration.

  By the way, although it is assumed to be applied to a relatively small-capacity container, Patent Document 1 discloses folding in a container shape called a so-called square bottle caused by a lateral load that decreases due to thinning. In order to improve the resilience against the curved deformation, the vertical ribs are formed in the shape of vertical grooves along the ridge formed at the boundary between the flat side wall of the container body and the corner wall chamfered at the corner. Disposed synthetic resin containers are disclosed.

JP 2011-31906 A

  However, as a result of intensive studies by the present inventors, depending on the container shape as disclosed in Patent Document 1, it is not possible to sufficiently meet the demand for today's thinning which is becoming increasingly severe, In particular, in a container having a relatively large capacity, as described above, in order to compensate for a decrease in the vacuum absorption performance on the lower side of the container body, when trying to increase the vacuum absorption on the upper side of the container body, As the vacuum absorption panel provided on the upper side of the container body is greatly deformed inward of the container, the force to pull in the container also acts on the corner of the container, so that the corner is restored. It came to the knowledge that it was inadequate to make it exhibit sex.

  The present invention has been made in view of the circumstances as described above, and in a rectangular bottle-shaped synthetic resin container with chamfered corners, while improving the vacuum absorption performance under the demand for thinning the container. An object of the present invention is to provide a synthetic resin container capable of sufficiently exhibiting resilience to a shape change.

  A synthetic resin container according to the present invention is a rectangular bottle-shaped synthetic resin container having a mouth, a shoulder, a body, and a bottom, the body having a side surface and a chamfered corner. And forming a longitudinal groove-shaped ridge line groove portion on a ridge line portion formed at a boundary along the height direction between the side surface portion and the chamfered portion, and the ridge line groove portion on the chamfered portion. In this configuration, longitudinal grooves extending in parallel or substantially in parallel are formed.

According to the present invention, even if the container corner portion is deformed so that the container corner portion is pushed into the container by applying an external force or the like by providing the ridge groove portion and the longitudinal groove portion in the container corner portion, such a shape In addition to being able to satisfactorily exhibit the restoring force against changes , the above-mentioned effects can be obtained by providing a convex portion having a surface that is flush with the outer surface of the chamfered portion in the longitudinal groove portion formed in the chamfered portion. Without impairing the appearance, it is possible to avoid irregular shrinkage when the shrink film is thermally shrunk and to be mounted, so that the appearance is not deteriorated .

It is a perspective view which shows the synthetic resin container which concerns on embodiment of this invention. It is a front view which shows the synthetic resin container which concerns on embodiment of this invention. It is a side view which shows the synthetic resin container which concerns on embodiment of this invention. It is a top view which shows the synthetic resin container which concerns on embodiment of this invention. It is a bottom view showing a synthetic resin container according to an embodiment of the present invention. It is AA sectional drawing of FIG. It is a principal part enlarged view which shows the example of the vertical groove part formed in the chamfering part of an upper trunk | drum part. It is BB sectional drawing of FIG. It is CC sectional drawing of FIG. It is a principal part enlarged view which shows the example of a leg part. It is a perspective view showing a reference example of a synthetic resin container according to an embodiment of the present invention. It is a front view showing a reference example of a synthetic resin container according to an embodiment of the present invention. It is DD sectional drawing of FIG.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a synthetic resin container according to the present embodiment, FIG. 2 is a front view thereof, FIG. 3 is a side view thereof, FIG. 4 is a plan view thereof, and FIG. FIG.

  First, the outline of the container 1 in the present embodiment will be described.

  In the present embodiment, the container 1 is formed, for example, by molding a bottomed cylindrical preform by injection molding or compression molding using a thermoplastic resin, and the preform is formed by biaxial stretch blow molding, as shown in FIG. As shown in FIG. 4, the container is manufactured by molding into a predetermined container shape having a mouth portion 2, a shoulder portion 3, a trunk portion 4, and a bottom portion 5.

  In manufacturing such a container 1, as a thermoplastic resin to be used, any resin capable of forming the container 1 as described above can be used. Specifically, thermoplastic polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyarylate, polylactic acid or copolymers thereof, those blended with these resins or other resins are suitable. It is. In particular, an ethylene terephthalate thermoplastic polyester such as polyethylene terephthalate is preferably used. Further, acrylonitrile resin, polypropylene, propylene-ethylene copolymer, polyethylene and the like can be used.

  The mouth portion 2 provided in the container 1 is a cylindrical portion in which a screw portion 21 for attaching a lid (not shown) is formed. In addition, the position where the diameter starts to expand toward the trunk portion 4 is included at the boundary between the mouth portion 2 and the shoulder portion 3, including a portion having the same diameter immediately below the support ring 22 generally formed in this type of container. BL1 (see FIG. 2).

  The shoulder 3 is a truncated pyramid-shaped part that is located between the mouth 2 and the body 4 and is connected to the mouth 2 while being narrowed down from the upper end of the body 4. And the position where narrowing is started toward the mouth 2 is defined as a boundary BL2 between the body 4 and the shoulder 3 (see FIG. 2).

  Moreover, the trunk | drum 4 is a site | part formed in the rectangular tube shape which occupies most of the height direction of the container 1, the cross-sectional shape orthogonal to a height direction is made into the substantially same shape, and a corner | angular part is chamfered. It has a rectangular shape. Thereby, the trunk | drum 4 is comprised by the two sets of side parts 41 which oppose, and the chamfering part 42 located between each side part 41, and the container 1 is made into what is called a square bottle-shaped container shape. .

  Here, the height direction means a direction orthogonal to the horizontal plane when the container 1 is erected on the horizontal plane with the mouth portion 2 up, and in this state, the vertical, horizontal, vertical and horizontal directions of the container 1 are defined. Shall be defined. Further, in the container 1 shown in FIG. 1 and the like, the side surface portion 41 is located on the long side of the trunk portion 4 having a rectangular cross section, and on the short side, the side portion 41 is described. Only when it is necessary, “the side part 41 on the long side” and “the side part 41 on the short side” are distinguished from each other.

  Moreover, the trunk | drum 4 is divided into the upper trunk | drum 4a and the lower trunk | drum 4b by the waist part 40 formed so that a part of trunk | drum 4 might be narrowed down to radial direction. Such a waist portion 40 is formed along the circumferential direction of the trunk portion 4 in order to increase the rigidity near the center in the height direction of the container 1. When the waist portion 40 is formed by narrowing a part of the body portion 4 in the radial direction, the positions where the narrowing starts are the boundary BL3 between the upper body portion 4a and the waist portion 40, and the lower body portion 4b and the waist portion 40, respectively. And a boundary BL4 (see FIG. 2).

  Moreover, the bottom part 5 refers to a lower part that has been narrowed down from the lower end of the body part 4, and a position where the narrowing starts is defined as a boundary BL5 between the body part 4 and the bottom part 5 (see FIG. 2).

  Next, the structure of each part of the container 1 in this embodiment is demonstrated.

  As described above, the body portion 4 is divided into the upper body portion 4a and the lower body portion 4b by the waist portion 40, and the upper body portion 4a and the lower body portion 4b are respectively provided with a vacuum absorbing panel on each side surface portion 41. 45a and 45b are provided. The vacuum absorption panels 45a and 45b are for preventing uneven change in the shape of the container 1 due to a decrease in internal pressure after filling and sealing the contents in the container 1, and according to the required vacuum absorption performance. Various panel shapes can be adopted.

For example, the container 1 shown in FIG. 1 and the like is an example of a container having a capacity of 2L. In such a container 1 having a relatively large capacity, the lower body part 4b positioned on the lower side of the body part 4 is provided. , Tends to swell due to its own weight. For this reason, the decompression absorption panel 45b provided in the lower trunk | drum 4b is the panel shape which gave priority to ensuring rigidity rather than a decompression absorption capability in order to suppress that the lower trunk | drum 4b swells with the dead weight of the content. Is adopted.
On the other hand, since the upper body part 4a located on the upper side of the body part 4 is relatively less affected by the weight of the contents, the reduced pressure absorption panel 45a provided on the upper body part 4a has a panel shape with high reduced pressure absorption performance. Is employed so that the vacuum absorption required for the entire container is exhibited.

  Moreover, in the container 1 shown in FIG. 1 etc., the recessed part 46a is provided in the position along the boundary BL2 of the trunk | drum 4 and the shoulder part 3 in the side part 41 of the long side of the trunk | drum 4. ing. Similar concave portions 46b and 46c are also provided at positions along the boundary BL3 between the upper body portion 4a and the waist portion 40 and the boundary BL4 between the lower body portion 4b and the waist portion 40 (see FIG. 2). ).

  In the side surface portion 41 of the body portion 4, if a flat surface that is weak in strength exists in a relatively wide range from the boundary with the chamfered portion 42 to the decompression absorption panels 45 a and 45 b, A trace generally referred to as sink marks is likely to occur on a flat surface. Normally, when the molded container 1 is taken out of the mold, the container 1 is not sufficiently cooled. Therefore, if the flat surface is weak in strength in this state, the container 1 is deformed so as to be bent. It is thought that such sink marks will occur.

In forming this type of synthetic resin container by biaxial stretch blow molding, the residual temperature of the molded container 1 is removed, the crystallinity of the material resin is increased, and heat resistance is imparted. The molding may be performed at a high temperature (for example, the temperature is increased to about 150 ° C.). When the temperature of the mold is increased in this way, the material resin easily adheres to the mold, and the side surface portion 41 and the chamfered portion 42 are partially adhered to the mold during the opening of the mold, so Since the flat portion which is weak in strength is deformed so as to bend, the sink is likely to occur particularly in such a case. As described above, although there are various factors that cause sink marks, the occurrence of sink marks cannot be ignored as the container becomes thinner.
As described above, the concave portions 46a, 46b, and 46c are provided in the side surface portion 41, thereby providing a three-dimensional shape to increase the strength thereof, thereby preventing the occurrence of such sink marks.

  Concave portions 46a and 46b are provided at positions along the boundary BL2 between the body portion 4 and the shoulder portion 3, the boundary BL3 between the upper body portion 4a and the waist portion 40, and the boundary BL4 between the lower body portion 4b and the waist portion 40, respectively. , 46c, the specific form can be selected as appropriate according to the degree of occurrence of sink marks. The recessed portions 46a, 46b, 46c are not limited to being provided on the boundaries BL2, BL3, BL4, and may be provided on the upper side or the lower side of the boundaries BL2, BL3, BL4. In the container 1 shown in FIG. 1 and the like, the concave portions 46a, 46b, and 46c are provided on the side portion 41 on the long side, but the same concave portion is provided on the side portion 41 on the short side as necessary. A part may be provided.

11 is a perspective view showing a reference example (capacity 1L) of the synthetic resin container according to the present embodiment, FIG. 12 is a front view thereof, and FIG. 13 is a view in which the thickness of the container 1 is omitted. It is DD sectional drawing of 12. FIG. As shown in these drawings, a recessed portion 46d may be provided at a position along the boundary BL5 between the body portion 4 and the bottom portion 5. Further, in such a reference example , a reinforcing recess 48 as shown in FIG. 11 or the like can be provided in the vicinity of the upper end and the lower end of the chamfered portion 42 in each of the upper body portion 4a and the lower body portion 4b. .
In addition, in the reference example shown in FIG. 11 etc., about the component corresponding to the container 1 shown in FIG. 1 etc., the description is abbreviate | omitted by attaching | subjecting the same code | symbol.

As described above, in this embodiment, any one of the recessed portions 46a, 46b, 46c, and 46d is provided at a position along at least one of the boundaries BL2, BL3, BL4, and BL5. 42 by providing a three-dimensional shape to one or both of the upper end side and the lower end side of the flat surface formed between the boundary with the lower pressure absorption panels 45a and 45b and increasing the strength thereof. Even if there are flat surfaces extending in a relatively wide range on the left and right side edges of the panels 45a and 45b, the occurrence of sink marks at the time of molding on these surfaces can be suppressed. The shapes, dimensions, etc. of the recessed portions 46a, 46b, 46c, 46d are appropriately determined from the viewpoint of effectively suppressing the occurrence of sink marks, but the lateral lengths of the recessed portions 46a, 46b, 46c, 46d are chamfered. It is set to a length that fits between the boundary with the portion 42 and the decompression absorption panels 45a and 45b. Further, the recessed portions 46a, 46b, 46c, and 46d are provided at locations other than the ridge line groove portion 43 described later.
In addition, the container 1 shown in FIG. 1 etc. has the ditch | groove 49a provided along the lower end of the side part 41 of the trunk | drum 4, and the ditch | groove 49b provided along the lower end of the chamfer 42 of the trunk | drum 4. Have. Providing such concave grooves 49a and 49b can suppress the occurrence of sink marks in the vicinity of the concave grooves 49a and 49b, but these can be omitted as necessary. In particular, when the concave groove 49a provided along the lower end of the side surface portion 41 of the trunk portion 4 is omitted, the trunk portion 4 and the container 4 shown in FIG. You may make it suppress the generation | occurrence | production of a sink by providing a recessed part (equivalent to the recessed part 46d in the modification shown in FIG. 11 etc.) in the position along boundary BL5 with the bottom part 5. FIG.

  Further, the shoulder 3 of the container 1 shown in FIG. 1 and the like has a first inclined portion 31 squeezed from the upper end of the trunk portion 4 and a second inclined that is further squeezed from the first inclined portion 31 and connected to the mouth portion 2. It consists of part 32. And the decompression absorption panel 45a provided in the side part 41 of the long side of the upper trunk | drum 4a goes over the boundary BL2 of the trunk | drum 4 and the shoulder part 3, and reaches the 1st inclination part 31 of the shoulder part 3. FIG. (See FIG. 2).

Usually, this type of synthetic resin container is provided with a belt-like label made of a heat-shrinkable shrink film for sale. In the container 1 shown in FIG. 1 and the like, the stepped portion 33 serving as a hanging portion on the upper edge side of the label is along the boundary BL6 between the first inclined portion 31 and the second inclined portion 32 of the shoulder portion 3. Thus, it is formed so as to be positioned above the reduced pressure absorption panel 45a. And in this embodiment, the bending guide part 34 which is depressed in the shape of a trough is formed in the horizontal center of this step part 33 substantially.
Here, FIG. 6 is a cross-sectional view taken along the line AA of FIG. 2 in which the thickness of the container 1 is omitted, and shows a cross section obtained by cutting a portion where the step portion 33 extends along a horizontal plane.

  As described above, in the container 1 having a relatively large capacity, a panel shape having high decompression absorption performance is adopted for the decompression absorption panel 45a provided in the upper body portion 4a. By forming the bending guide portion 34 at the substantially horizontal center of the step portion 33 positioned above the decompression absorbing panel 45a, the decompression absorption panel is started from the bending guide portion 34 while maintaining the label hanging by the step portion 33. 45a is bent at the center in the horizontal direction so as to be greatly deformed inward of the container, and thereby, a higher vacuum absorption performance can be exhibited.

In order to sufficiently exhibit such an effect, the bending guide portion 34 is preferably formed so that a ridge line appears along the height direction at the bottom of the valley that is recessed into the valley shape.
Moreover, the shoulder part 3 of the container 1 shown in FIG. 1 etc. is provided with the same step part 33 and the bending | flexion guide part 34 also in the short side. Accordingly, the reduced pressure absorption performance of the reduced pressure absorption panel 45a provided on the side surface portion 41 on the short side of the upper body portion 4a is also enhanced.

  As described above, in the present embodiment, the step portion 33 extending in the horizontal direction is formed above the reduced pressure absorption panel 45a as a hanging portion on the upper edge side of the label attached to the container 1, and this step By forming a bent guide part 34 that is recessed in a valley shape in the substantially horizontal center of the part 33, the vacuum absorption panel 45a is greatly deformed inward of the container so as to be bent at the horizontal center, thereby High vacuum absorption performance is demonstrated. For this reason, the range of selection of the panel shape of the reduced pressure absorption panel 45a is not limited, and in consideration of the balance between the rigidity required for the container 1 and the reduced pressure absorption performance under the demand for thinning the container 1. The vacuum absorption performance can be enhanced while arbitrarily adopting a suitable panel shape.

Moreover, in the container 1 shown in FIG. 1 etc., the ridgeline formed in the boundary along the height direction of the adjacent side surface part 41 and the chamfered part 42 in any of the upper trunk | drum 4a and the lower trunk | drum 4b. In the portion, a longitudinal groove-shaped ridge line groove portion 43 is formed along the ridge line portion.
In the upper trunk portion 4a, the ridge line groove portion 43 is formed so as to extend from the vicinity of the boundary BL2 between the trunk portion 4 and the shoulder portion 3 to the vicinity of the boundary BL3 between the upper trunk portion 4a and the waist portion 40. The lower body 4b is formed so as to extend from the vicinity of the boundary BL4 between the lower body 4b and the waist 40 to the vicinity of the boundary BL5 between the body 4 and the bottom 5 (see FIG. 2).
The above-mentioned boundaries BL1 to BL6 are boundaries orthogonal to the height direction, and are distinguished from the boundaries along the height direction between the side surface portion 41 and the chamfered portion 42 (portions where the ridge line groove portion 43 is formed). Is done.

  Further, as shown in FIG. 8, the ridge line groove portion 43 has a groove shape with a V-shaped cross section as shown in the figure in which the groove side surfaces intersect at the straight groove bottom portion, and has a groove bottom portion with a predetermined width. A groove shape having a trapezoidal cross section in which the groove side surface rises from both edges in the width direction of the groove bottom portion may be used.

Further, in the container 1 shown in FIG. 1 and the like, in the upper body portion 4a, such a ridge line groove portion 43 is formed, and the chamfered portion 42 extends in parallel or substantially parallel to the ridge line groove portion 43. A vertically long groove portion 44 is formed.
In addition, in the front view shown in FIG. 2, the longitudinal groove part 44 formed in the chamfer 42 of the upper trunk | drum 4a and its vicinity are expanded and shown to Fig.7 (a).

  When an external force is applied to the corner portion of the upper trunk portion 4a and the corner portion is deformed so as to be pushed inward of the container, it is deformed so that a broken line is generated in a direction perpendicular to the height direction. By providing the longitudinal groove portion 44 in addition to the ridge line groove portion 43 so as to be orthogonal to the polygonal line, it is possible to satisfactorily exert a restoring force against such a shape change and to suppress permanent deformation of the container 1. . In particular, when the container 1 is further thinned, a sufficient restoring force cannot be expected only by the ridge line groove portion 43, so that a sufficient restoring force can be exhibited even in such a case. In addition to the ridge line groove portion 43, it is effective to provide the vertical groove portion 44 together.

In order to exert such a restoring force, it is preferable that the longitudinal groove portion 44 is formed so as to be symmetrical with respect to the center in the width direction of the chamfered portion 42.
However, when a strip-shaped label made of a heat-shrinkable shrink film is attached to the container 1, the wrap margin on which the edge of the label is superimposed is positioned at the center in the width direction of the chamfered portion 42, The label is positioned. At this time, if the back side of the wrap margin is hollow, the label may be irregularly contracted when thermally contracted, resulting in poor appearance.

For this reason, when forming the vertical groove 44 in the chamfered portion 42 in the center of the chamfered portion 42 in the width direction, the vertical groove 44 is flush with the outer surface of the chamfered portion 42. The convex part 44a which has a surface is provided, and the lapping margin of a label is supported by this convex part 44a .
8 (a) is a B-B sectional view of FIG. 2 is omitted the thickness of the container 1.

Moreover, in the container 1 shown in FIG. 1 etc., the ridge line groove part 43 formed in the lower trunk | drum 4b is formed with the convex rib 43a so that it may be spanned between the groove side surfaces which oppose.
As described above, in the container 1 having a relatively large capacity, the lower body part 4b located on the lower side of the body part 4 tends to easily swell due to its own weight. At this time, if the ridge line groove portion 43 formed in the lower body portion 4b is deformed so as to be expanded from the inside of the container by the weight of the contents, the bulge of the lower body portion 4b is promoted.

  In order to suppress such deformation, a convex rib 43a is provided between the opposing groove side surfaces in the ridge line groove portion 43 formed in the lower body portion 4b. The position in the ridge line groove 43 where such a convex rib 43a is formed is appropriately selected according to the length, width, etc. of the ridge line groove 43. In the illustrated example, two convex ribs 43 a are formed in the ridge line groove portion 43 at equal intervals. At this time, when the upper surface of the convex rib 43a is flush with the outer surface of the chamfered portion 42, the ridge line groove portion 43 is divided by the convex rib 43a, and the functions such as the resilience and the rigidity improvement by the ridge line groove portion 43 are impaired. Therefore, it is preferable that the height of the convex rib 43 a is designed to be within the ridge line groove portion 43.

  Further, a plurality (six in the illustrated example) of recessed portions 47 are arranged in the chamfered portion 42 of the lower body portion 4b along the height direction. The chamfered portion 42 is reinforced by such a recessed portion 47, and the swelling of the lower body portion 4b due to the weight of the contents can be more effectively suppressed.

  Further, the bottom 5 of the container 1 shown in FIG. 1 and the like has a dome-shaped raised bottom 50 formed at the center of the bottom surface side, and a heel portion 51 that extends from the lower end edge of the body portion 4 to the bottom surface side of the bottom 5. have. Further, at the four corners of the bottom portion 5, leg portions 52 each including a grounding portion 54 positioned on the bottom surface side of the bottom portion 5 and a side portion 53 connected to the grounding portion 54 and extending outward from the container are provided. And the groove part 55 arrange | positioned radially centering on the center of the bottom part 5 is formed in the side part 53 of each leg part 52 (refer FIG. 5).

FIG. 9 is a cross-sectional view taken along the line CC of FIG. 5. The groove 55 is preferably formed with an angle α of 5 to 40 ° with respect to the horizontal plane when the container 1 is set upright on the horizontal plane. And a groove side surface 55b rising from both end edges of the groove bottom portion 55a. The angle formed by the groove bottom 55a and the groove side surface 55b is preferably 30 to 60 ° in consideration of mold opening. Although not particularly illustrated, the groove portion 55 may have a groove shape with a V-shaped cross section with the groove bottom portion 55a being linear.
In addition, while enlarging the part enclosed with a dashed-dotted line in FIG. 5, it shows in FIG. 10 the part which contacts the said horizontal surface when the container 1 is made to stand upright on the horizontal surface. The shaded portion is the grounding portion 54. In the container 1 shown in FIG. 1 and the like, the grounding portion 54 is partially cut away by the groove portion 55, and the container 1 is attached to the base end side of the groove bottom portion 55a. It is formed so as to be in line contact with an upright horizontal plane.

The load applied to the container 1 from the vertical direction is transmitted to the bottom surface side of the bottom portion 5 through the leg portions 52 provided at the four corners of the bottom portion 5. At this time, a force that greatly deflects the periphery of the leg 52 acts, and there is a concern that this force compresses the bottom surface side of the bottom 5 in the circumferential direction to cause wrinkles. In particular, when the container 1 is packed and transported, if the wrinkles are repeatedly generated on the bottom surface side of the bottom portion 5 due to the vibration, the wrinkles are woven and a protruding portion is generated in the bottom portion 5, and the container 1 is tilted upright. Furthermore, it is conceivable that pinholes are generated in the protruding portion and the contents leak out, and countermeasures against such problems are increasingly required as the container becomes thinner.
When the groove portions 55 as described above are formed in each of the leg portions 52 provided at the four corners of the bottom portion 5, when the load from the vertical direction is applied to the container 1, the leg portions 52 are deformed so as to bend in the groove portion 55 direction. As a result, the leg 52 is deformed so as to bend along the height direction, and the load is dispersed. As a result, the force for compressing the bottom surface side of the bottom portion 5 in the circumferential direction is alleviated, so that problems such as wrinkles on the bottom surface side of the bottom portion 5 can be suppressed.

  Further, in many cases, the container 1 having a capacity of 2L shown in FIG. 1 is filled with six contents in a carton after being filled with contents such as a beverage. At this time, the four containers 1 housed on both sides are pressed against the inner flap, but the two containers in the center are in a free state, so the four containers housed on both sides 1 will receive the load. When the groove portions 55 as described above are formed in the respective leg portions 52 provided at the four corners of the bottom portion 5, the leg portions 52 are deformed so as to be bent, and the height of the container 1 is lowered accordingly. As a result, even when the carton is packed in a box and is piled up, it becomes possible to receive a load in all the containers 1 accommodated, and the load per bottle is reduced, and all the containers 1 Since the load is supported by the carton, the carton strength is improved as a result.

  Although the present invention has been described with reference to the preferred embodiments, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention. Nor.

  For example, the container 1 shown in FIG. 1 and the like described in the above embodiment has a capacity of 2L, and the container 1 shown in FIG. 11 and the like has a capacity of 1L. The present invention is suitable for such a synthetic resin container having a relatively large capacity, but the capacity of the synthetic resin container to which the present invention is applied can be appropriately changed as necessary. Needless to say, the details can be changed as the capacity is changed.

  Further, in the container 1 shown in FIG. 1 and the like described in the above-described embodiment, the cross-sectional shape of the trunk portion 4 is a rectangular shape with chamfered corners. However, like the container 1 shown in FIG. The cross-sectional shape of the portion 4 may be a square shape with chamfered corners.

  In the above-described embodiment, the container 1 has a waist portion 40 formed of an annular recess along the circumferential direction at approximately the center of the body portion 4 in the height direction. It may be omitted if necessary.

  The present invention as described above can be suitably used for a rectangular bottle-shaped synthetic resin container.

DESCRIPTION OF SYMBOLS 1 Container 2 Mouth part 3 Shoulder part 4 trunk | drum 4a upper trunk | drum 4b lower trunk | drum 40 waist part 41 side part 42 chamfering part 43 ridgeline groove part 43a convex rib 44 vertical groove part 44a convex part 5 bottom part

Claims (3)

A rectangular bottle-shaped synthetic resin container having a mouth, a shoulder, a body, and a bottom,
The body portion includes a side surface portion and a chamfered portion formed by chamfering a corner portion,
Rutotomoni longitudinal groove-like ridge groove is formed in the ridge portion formed at the boundary along the height direction of the chamfered portion and the side surface portion,
The chamfered portion is formed with a vertical groove portion extending in parallel or substantially parallel to the ridge line groove portion, and a convex portion having a surface flush with the outer surface of the chamfered portion is provided in the vertical groove portion. A synthetic resin container. The trunk is divided into an upper trunk and a lower trunk by a waist;
The upper of the lower body portion and the body portion, the synthetic resin container according to claim 1, wherein the longitudinal groove portion the ridge grooves and on said body portion is juxtaposed. To become symmetrical with respect to the width direction center of the chamfered portion, the synthetic resin container according to claim 1 or 2, wherein the longitudinal groove is formed.

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