JP6910767B2 - Thin plastic bottle - Google Patents

Description

The present invention relates to thin-walled plastic bottles.

In recent years, it has been required to reduce the amount of resin used for plastic bottles and save resources and costs, and for that purpose, attempts have been made to reduce the thickness of plastic bottles. However, there is a problem that the plastic bottle becomes soft due to the thinning, and when the user holds the plastic bottle in his / her hand, the plastic bottle is easily deformed and difficult to hold.

To solve this problem, ribs are provided in plastic bottles, and in order to improve the strength of thin-walled plastic bottles, deep peripheral ribs having a depth of 2.5 mm or the like are generally provided. In this case, ribs are provided. There was a problem that the plastic bottle was bent when the roll label was attached.

Therefore, it is desired to realize a thin-walled plastic bottle that maintains the strength of the bottle and further improves the production suitability.

The thin-walled plastic bottle according to the present invention
On the body of the bottle body, a panel portion having a panel recessed inside the bottle body, a first rib area arranged on the upper side of the panel portion, and a second rib arranged on the lower side of the panel portion. A region is provided, and a plurality of peripheral ribs having a depth of 1.5 mm or less are formed adjacent to each other in the first rib region and the second rib region, and the full filling capacity is provided. ratio 0.017~0.041g / ml der amount of resin for is, a vertical length ratio of the panel for the entire length from 0.13 to 0.20, the said panel portion is provided In the body portion, the cross-sectional shape of the surface orthogonal to the axis of the thin-walled plastic bottle is octagonal .

According to this configuration, in a thin-walled plastic bottle, a plurality of peripheral ribs having a depth of 1.5 mm or less, which is shallower than before, are provided on the body of the bottle body, so that the peripheral ribs are not provided over the entire area of the bottle body. It is possible to prevent the bottle from bending when the roll label is attached, while maintaining the strength of the bottle. Furthermore, when the user holds the bottle by grasping the body of the bottle, in this configuration, the body of the bottle, which is the handle, is provided with a rib region that is difficult to deform, so that the deformation when holding the bottle is suppressed. , The ease of holding the bottle is also improved.

Further, when it is deeper than the peripheral rib having the above configuration, the portion where the peripheral rib is provided can increase the strength of the bottle when the user grips it, but the desired smoothness for attaching the roll label after molding. Although the surface may not be reproduced stably, by setting the depth of the peripheral rib to 1.5 mm or less, the reproducibility of the smooth surface can be ensured while maintaining the strength required for gripping by the user.

As one embodiment, it is preferable that a smooth region is provided between the peripheral ribs in the first rib region and the second rib region.

According to this configuration, since a smooth region is provided, if a label is attached to this region, it becomes easier to attach the label.

As one embodiment, it is preferable that the first rib region and the second rib region are label sticking regions.

According to this configuration, since the rib area is provided in the area where the roll label is attached, it is possible to suitably prevent the bottle from bending when the roll label is attached. Furthermore, when the user holds the bottle by grasping the sticking area, the label of the bottle has a rib area in the sticking area where the label as the handle is hard to be deformed, so that when the bottle is held, the user holds the bottle. Deformation is suppressed and the ease of holding the bottle is further improved.

Front view of plastic bottle Enlarged view of the upper part of the bottle Partial sectional view of a pair of bent portions Enlarged view of the lower part of the bottle VV cross-sectional view in FIG. Enlarged view of the bottom Bottom view of the bottom Partial sectional view of a pair of bent portions in another embodiment Partial sectional view of a pair of bent portions in another embodiment Partial sectional view of a pair of bent portions in another embodiment Bottom view of the bottom in another embodiment XII-XII sectional view in FIG.

An embodiment of a thin-walled plastic bottle according to the present invention will be described with reference to the drawings. As shown in FIG. 1, the plastic bottle 1 according to the present embodiment includes a mouth portion 2 as a liquid spout and a bottle body portion 3 filled with a liquid. The bottle body 3 has a shoulder portion 4 that is continuous with the mouth portion 2 and gradually increases in diameter toward the bottom surface, a cylindrical body portion 5 that is continuous with the shoulder portion 4, and a bottom portion that is the bottom of the plastic bottle 1. It is composed of 6. The upper portion 10 of the bottle extending from the upper region 5a of the body portion 5 to the shoulder portion 4 is decorated for a design effect. On the other hand, a reinforcing structure for absorbing reduced pressure is adopted in the lower portion 20 of the bottle extending from the lower region 5b of the body portion 5 to the bottom portion 6. So to speak, the plastic bottle 1 according to the present embodiment has a structure divided into a bottle upper portion 10 as a decorated decorative region and a bottle lower portion 20 as a decompression absorption and reinforcement region. There is.

The plastic bottle 1 can be integrally molded by a stretching molding method such as biaxial stretching blow molding using a thermoplastic resin such as polyethylene, polypropylene, or polyethylene terephthalate as a main material. The capacity of the plastic bottle 1 is not particularly limited, and can be about 200 ml to 2 liters that are generally distributed. The liquid to be filled in the bottle 1 is not particularly limited, and for example, beverages such as drinking water, tea, fruit juice, coffee, cocoa, soft drinks, alcoholic beverages, milk beverages, soups, and liquid seasonings such as sauces and soy sauce. Fees and the like can be mentioned.

Further, the plastic bottle 1 of the present embodiment is made thinner than that for general beverages in order to save resources and costs. Specifically, the ratio of the amount of resin (g) of the plastic bottle 1 to the full filling capacity (ml) of the plastic bottle 1 is 0.017 to 0.041 (g / ml), more preferably 0.023 to 0. It is preferable that it is formed so as to be 037. If the ratio of the amount of resin to the full volume exceeds 0.041 (g / ml), it cannot be said that the bottle is thin and lightweight, while the ratio of the amount of resin to the full volume is 0.017 (g / ml). ), The wall thickness becomes too thin, and the strength cannot be secured even with the structure of the present embodiment described later.

Since thinning in this way causes problems in strength, in this type of thin-walled plastic bottle, when the bottle is deformed due to the horizontal load of the thin-walled plastic bottle or when the pressure is reduced due to temperature changes, the pressure is reduced. Reinforcing structures such as ribs are often provided throughout the bottle to prevent the bottle from denting because it cannot withstand, and to improve the ease of holding the bottle when the user holds the bottle. .. However, in the plastic bottle 1 of the present embodiment, as described above, the upper portion 10 of the bottle is used as a decorative area, and a reinforcing structure cannot be provided as a whole. Therefore, instead, the lower portion 20 of the bottle is characterized. It is supposed to be equipped with a typical reinforcing structure. Further, the upper portion 10 of the bottle as a decorative area also has a reinforcing structure incorporated in the decorative shape. This makes it possible to effectively suppress deformation due to load. Hereinafter, the structures of the bottle upper portion 10 and the bottle lower portion 20 will be described.

[Bottle upper part 10]
As shown in FIG. 1, the upper surface of the bottle 10 is embossed with irregularities on the entire surface of the upper bottle 10 as a decoration (in FIG. 2, the irregularities due to the embossing are omitted for simplification. ing). Then, as shown in FIGS. 1 and 2, a band-shaped region defined by two frame lines (bent portions 12, 13) is formed in the bottle upper portion 10, and a plurality of decorations are formed in the band-shaped region. Part (character ABCDEFGH in this embodiment) 11 is formed. As described above, the upper portion 10 of the bottle has a design appearance, and the design effect is aimed at by this. The plastic bottle 1 of the present embodiment incorporates the following reinforcing structure while exhibiting such a design appearance.

First, the unevenness of the entire upper surface of the bottle 10 due to embossing enhances the strength of the upper portion of the bottle in addition to the decorative effect.

Further, in the plastic bottle 1 of the present embodiment, in the bottle upper portion 10, at least one or more bent portions 12 and 13 whose surfaces are bent inward or outward of the bottle 1 are all around the bottle upper portion 10. More specifically, as shown in FIGS. 1 and 2, two, more strictly, a pair of bent portions 12, 13 extend over the entire circumference of the upper portion 10 of the bottle. Is formed of. The pair of bent portions 12 and 13 function as the above-mentioned frame line. Specifically, in the present embodiment, as shown in FIG. 3, the upper bent portion 12 has a step whose surface is bent outward from the bottle 1, and the lower bent portion 13 has the surface of the bottle 1. It is a concave rib (more specifically, a mountain shape with a V-shaped cross section) that bends inward. Since the upper bent portion 12 has a step, the band-shaped region between the bent portions 12 and 13 is formed by the stepped surface portion 15 protruding from the upper region 14 of the upper bent portion 12. ..

Further, the pair of bent portions 12 and 13 are both wavy, and extend in a synthetic wavy shape in which a low-frequency wave having a large amplitude and a high-frequency wave having a small amplitude are combined. More specifically, a low-frequency regular wave with a large amplitude in which peaks and valleys appear twice in one round is combined with an irregular wave with a smaller amplitude and a higher frequency and a saw blade shape than this low-frequency wave. It is a synthetic wave, with two large peaks and valleys in one round, and a shape in which small saw blade-shaped peaks and valleys appear between them. Then, the peak portion of the upper bending portion 12 and the valley portion of the lower bending portion 13 coincide with each other, and the valley portion of the upper bending portion 12 and the peak portion of the lower bending portion 13 coincide with each other. The pair of bent portions 12 and 13 have symmetrical shapes. Therefore, in the pair of bent portions 12 and 13, the peak portion in the low-frequency regular wave of the upper bent portion 12 and the valley portion in the low-frequency regular wave of the lower bent portion 13 coincide with each other. The first part 16 with a wider interval, the valley part in the low frequency regular wave of the upper bending part 12, and the peak part in the low frequency regular wave of the lower bending part 13 coincide with each other. The second part 17 and the narrowed second portion 17 are provided. As a result, the stepped surface portion 15, which is a band-shaped region between the bent portions 12 and 13, is provided with a wide region and a narrow region.

As described above, the bottle upper portion 10 is provided with a pair of bent portions 12 and 13 for strength reinforcement, and further, by forming the pair of bent portions 12 and 13 into a synthetic wavy shape, the bottle upper portion is formed. The strength of the can be effectively increased. Further, by providing the pair of bent portions 12 and 13 with the first portion 16 in which the distance between the bent portions 12 and 13 is widened and the second portion 17 in which the distance between the bent portions 12 and 13 is narrowed, the region between the bent portions 12 and 13 becomes a distorted shape. , Deformation of the region between the bent portions 12 and 13 can be effectively suppressed. As a result, deformation due to decompression can be effectively suppressed.

Further, the stepped surface portion 15 is separated from other regions by the bent portions 12 and 13, and can be said to be a portion where deformation is likely to occur. The stepped surface portion 15 is a region between the bent portions 12 and 13. A plurality of convex decorative portions (characters ABCDEFGH in the present embodiment) 11 having a predetermined shape are formed, and the decorative portions 11 enhance the strength of the region between the bent portions 12 and 13. Then, in the present embodiment, in particular, the decorative portion 11 is formed in the regions on both sides corresponding to the first portion 16 (that is, not only in the regions shown in FIGS. 1 and 2 but also in the region on the back side thereof). There is. That is, the region corresponding to the second portion 17 in which the distance between the two is narrowed is a region having particularly high strength due to the narrow range, while the region 16 in the first portion 16 in which the distance between the two is widened is only the expanded portion. Although it can be said that it is easily deformed, the strength is increased because the decorative portion 11 having a reinforcing function is provided in the first portion 16, and the strength of the region between the bent portions 12 and 13 can be increased as a whole. By providing the decorative portion 11 only in the region corresponding to the first portion 16, not only the strength is increased, but also all the decorative portions 11 can be seen from one direction, which is preferable in terms of appearance. ing.

As described above, the upper portion 10 of the bottle as a decorative area has a reinforcing structure incorporated in the decorative shape, whereby deformation due to decompression is effectively suppressed. Will be done.

[Bottle lower part 20]
As shown in FIGS. 1 and 4, in the lower portion 20 of the bottle, a plurality of panels 22 recessed in the radial direction are arranged in the circumferential direction of the body portion in the portion corresponding to the lower region 5b of the body portion 5 (in the present embodiment). 8) Panel portions 21 formed at equal intervals are provided. As a result, when decompression occurs due to a temperature change or the like, the panel 22 of the panel portion 21 deforms the panel 22 to effectively absorb the decompression. In particular, in the present embodiment, the panel portion 21 is provided at an upper position in the lower region 5b of the body portion 5. The upper position in the lower region 5b is a position where a person can easily grasp the PET bottle, and by providing the panel portion 21 at that position, the human finger fits into the panel 22 and the ease of holding is improved. do.

Specifically, the shape of the panel 22 will be described in detail. As shown in FIGS. A second concave portion 22b, which is further recessed in the radial direction, is formed in the center of the above in the vertical direction. By having such a second recess 22b that is further recessed in the radial direction, the reduced pressure can be absorbed more effectively.

Further, in the present embodiment, the ratio of the length of the panel 22 in the vertical direction to the total length of the bottle 1 is 0.13 to 0.20. If the ratio of the vertical length of the panel 22 to the total length of the bottle 1 is less than 0.13, the panel is too short to obtain a sufficient decompression absorption effect, and the length ratio is 0.20. If it exceeds, the panel will be too long and the buckling strength of the entire bottle will decrease. In the present embodiment, the length of the panel 21a in the vertical direction is 35 mm with respect to the total length of the bottle of 222 mm, and the ratio is about 0.16.

The lower portion 20 of the bottle is provided with a first rib region 24 in which a plurality (three in the present embodiment) of concave peripheral ribs 23 are adjacent to each other on the upper side of the panel portion 21. The first rib region 24 is a label pasting region for sticking a roll label to the bottle 1, and is substantially located in a central region in the vertical direction of the bottle body 3. The peripheral rib 23 is formed so that the depth of depression inside the bottle body 3 is 1.5 mm or less. For example, in the present embodiment, the depth is 1.2 mm. As a result, the strength of the bottle body can be maintained without providing the peripheral ribs 23 over the entire area of the bottle body 3, and the bottle can be prevented from bending when the roll label is attached. Further, the user holds the bottle 1 by grasping the label sticking area of the bottle 1 or the central area. Since the area 24 is provided, deformation when holding the bottle is suppressed, and the ease of holding is also improved.

Further, a second rib region 25 in which a plurality of peripheral ribs 23 similar to the first rib region 24 are adjacent to each other (two in the present embodiment) are formed at a predetermined interval below the first rib region 24. In the present embodiment, the panel portion 21 is sandwiched between the first rib region 24 and the second rib region 25. A flat region 26, which is a smooth surface, is provided between the peripheral ribs 23 in the first and second rib regions 24 and 25, respectively. The width between the first rib region 24 and the second rib region 25 is a width corresponding to the width of the label provided on the plastic bottle 1, and one side of the label is between the peripheral ribs 23 in the first rib region 24. The label can be preferably attached by attaching the label to the flat region 26 and attaching the other side of the label to the flat region 26 between the peripheral ribs 23 in the second rib region 25. Further, since the peripheral rib 23 is formed so that the depth of depression inside the bottle body 3 is 1.5 mm or less, a desired flat region 26 can be stably reproduced at the time of bottle molding. Is possible.

Further, in the lower portion 20 of the bottle, as described above, the panel portion is provided in the region between the first and second rib regions 24 and 25, whereby the panel portion is adjacent to the panel portion 21. A plurality of concave peripheral ribs 23 (three on the upper side and two on the lower side in the present embodiment) are provided on the upper and lower sides of the 21. The decompression absorption by the panel portion 21 is performed by the movement of the panel 22, but by providing the peripheral ribs 23 that are difficult to move up and down of the panel portion 21, the panel portion 21 can move more easily. As a result, the panel portion can absorb the reduced pressure more effectively. Further, from the viewpoint of appearance, it is preferable that the panel portion 21 is hidden by a label. Therefore, it is necessary to provide adhesive regions for the label above and below the panel portion 21, but a plurality of peripheral ribs 23 are provided above and below the panel portion 21. The area 26 between the ribs 23 is used as a label bonding place. Further, the user generally grasps the central region of the bottle 1 with the thumb and index finger, and the remaining middle finger, ring finger and little finger are attached to the lower region of the handle portion. The portion that the little finger touches is formed by the panel portion 21, and the middle finger, ring finger, and little finger fit into the panel 22, and the ease of holding is improved. In addition, as shown in FIG. 1, three similar peripheral ribs 23 are formed further below the second rib region 25.

As described above, since the lower portion 20 of the bottle has a characteristic reinforcing structure including the panel portion 21, the thin bottle 1 is dented by the reduced pressure while the upper portion 10 of the bottle where the line of sight is easily gathered is decorated. It is possible to effectively suppress the deformation of the roll label, and further, it is possible to suppress the deformation at the time of attaching the roll label while maintaining the strength against the load in the horizontal direction. In particular, conventionally, for thin-walled plastic bottles, it has not been considered effective to provide a panel because the panel causes a decrease in strength against a vertical load, but the bottle deformation due to decompression absorption is a problem. In the present embodiment, the thin-walled plastic bottle that decorates the bottle itself is provided with a panel 22 having an appropriate size to ensure strength against a vertical load and to provide a reduced pressure absorption capacity. The panel 22 is preferably applied to a thin-walled plastic bottle that decorates the bottle itself.

〔bottom〕
The plastic bottle 1 of the present embodiment has a special structure in the bottom portion 6 in addition to the above-mentioned bottle upper portion 10 and bottle lower portion 20 for withstanding a load or the like. This will be described below.

As shown in FIGS. 6 and 7, the bottom portion 6 has a grounding portion 30 that comes into contact with the installation surface such as a desk, and the inside of the bottle 1 (upper in FIG. 1) as it goes inward in the radial direction from the grounding portion 10. The central portion 31 that rushes in, the dome portion 32 that rushes further inside the bottle than the central portion 31, and the eight groove portions 33 that extend radially from the dome portion 32 in the center of the bottom portion 6 in a state where the ground contact portion 30 is divided in the circumferential direction. And are formed.

In the plastic bottle 1 of the present embodiment, the strength is increased by providing a groove portion in the bottom portion 6. Then, in the bottom portion 6, the ground contact portion 30 is located on the same circumference, and the length of the ground contact portion 30 in the circumferential direction changes according to the width of the groove portion 33 (that is, the length in the circumferential direction). The ratio of the total length of the grounding portion 30 in the circumferential direction (that is, the total length of the eight grounding portions 30) to the circumferential length of the grounding portion 30 is 0.55 or less. Is set to. As a result, the bottle 1 is prevented from tipping over when it is conveyed by a conveyor or the like. Specifically, when the bottle 1 is conveyed by a conveyor or the like, if there is a step or a speed change in the conveyor, the bottom 6 of the bottle 1 tries to follow the conveyor due to frictional resistance, and as a result, the bottle 1 falls over. There is a risk that it will end up. On the other hand, since the thin-walled bottle 1 is easily deformed, a phenomenon occurs in which the frictional force increases to some extent as the ground contact area increases as in the case of rubber. By reducing the ground contact area, the space between the conveyor and the bottom 6 is reduced. Friction resistance can be reduced. As a result, the bottle 1 is less likely to be affected by the step of the conveyor and the change in speed, so that the bottle 1 is prevented from tipping over when it is conveyed by the conveyor or the like. In the present embodiment, the circumferential length of each grounding portion 30 is about 10.8, the diameter of the grounding portion 30 is 52.8, and the circumferential length of the grounding portion 30 is relative to the circumferential length. The ratio of the total length is about 0.52 (10.8 × 8 / (52.8 × 3.14)).

[Other Embodiments]
Finally, other embodiments of the thin-walled plastic bottle according to the present invention will be described. The configurations disclosed in each of the following embodiments can be applied in combination with the configurations disclosed in other embodiments as long as there is no contradiction.

(1) In the above-described embodiment, a configuration in which only a pair of bent portions 12 and 13 are provided on the upper portion 10 of the bottle has been described as an example. However, the embodiment of the present invention is not limited to this, and the bottle upper portion 10 may be provided with only one or three or more bent portions.

(2) In the above-described embodiment, of the pair of bent portions 12 and 13, the upper bent portion 12 has a step whose surface is bent outward from the bottle 1, and the lower bent portion 13 has the surface of the bottle 1. It is formed of concave ribs that are bent inward, and the band-shaped region between the bent portions 12 and 13 is a stepped surface portion 15 that protrudes from the upper region 14 of the upper bent portion 12. Explained in the example. However, embodiments of the present invention are not limited to this. For example, as shown in FIG. 8, the pair of bent portions 12 and 13 are concave ribs, respectively, and the band-shaped region between the bent portions 12 and 13 is positioned in the radial direction at the same position as the upper region 14. It may be. Further, as shown in FIG. 9, the upper bent portion 12 has a step whose surface is bent inward of the bottle 1, and the lower bent portion 13 has a convex rib, which is between the bent portions 12 and 13. The strip-shaped region of the above may be a stepped surface portion 15 ′ that is depressed with respect to the upper region 14 of the upper bent portion 12. In addition, as shown in FIG. 10, the upper bent portion 12 has a step whose surface is bent outward of the bottle 1, and the lower bent portion 13 has a step whose surface is bent inward of the bottle 1. The strip-shaped region between the bent portions 12 and 13 may be a stepped surface portion 15 projecting from the upper region 14 of the upper bent portion 12 and the lower region of the lower bent portion 13. That is, at least the surfaces of the pair of bent portions 12 and 13 are bent inward or outward of the bottle 1, such as convex or concave ribs and steps whose surface is bent inward or outward of the bottle 1, respectively. The strip-shaped region between the bent portions 12 and 13 may be recessed with respect to the upper region 14 of the upper bent portion 12, and the radial position is the same as that of the upper region 14. But it may be.

(3) In the above-described embodiment, in the stepped surface portion 15, a plurality of convex decorative portions 11 having a character shape are formed in a region corresponding to the first portion 16 of the bent portions 12 and 13. Was explained as an example. However, embodiments of the present invention are not limited to this. The number of decorative portions 11 may be one instead of a plurality, and may be concave instead of convex. Further, the character is not limited to the character, and may have a predetermined shape such as some figure or pattern. In addition, the decorative portion 11 may be formed in the entire region between the bent portions 12 and 13, or the decorative portion 11 may be formed in another region such as the upper region of the upper bent portion 12. good.

(4) In the above-described embodiment, a configuration in which irregularities are formed by embossing on the entire surface of the upper portion 10 of the bottle has been described as an example. However, embodiments of the present invention are not limited to this. For example, unevenness may be formed by embossing only over the surface of the upper region 14 of the upper bent portion 12 in the bottle upper portion 10.

(5) In the above-described embodiment, a configuration in which the panel portion 21 is provided at an upper position in the lower region 5b of the body portion 5 and a plurality of concave peripheral ribs 23 are provided above and below the panel portion 21 has been described as an example. However, embodiments of the present invention are not limited to this. The panel portion 21 is not limited to the upper position in the lower region 5b of the body portion 5, and may be provided at an arbitrary position in the entire bottle 1 including the bottle upper portion 10 depending on the purpose. Further, the peripheral ribs 23 may or may not be provided collectively on either side of the panel portion 21 without being provided on the upper and lower sides, respectively. In addition, the upper and lower concave peripheral ribs 23 may be one instead of a plurality.

(6) In the above-described embodiment, in order to prevent the bottle 1 from tipping over when being conveyed by a conveyor or the like, the total length of the grounding portion 30 in the circumferential direction with respect to the circumferential length of the grounding portion 30 ( That is, the configuration in which the ratio of the total lengths of the eight grounding portions 30) is set to 0.55 or less has been described as an example. However, embodiments of the present invention are not limited to this. For example, as shown in FIGS. 11 and 12, the bottom portion 6 has a concave groove portion 33 extending radially from the center (dome portion 32) of the bottom portion 6 in a state where the ground contact portion 30 that is in contact with the installation surface is divided in the circumferential direction. And the recess 34 that cuts out the ground contact portion 30 inside the bottle between the adjacent groove portions 33, and the depth of the recess 34 may be shallower than the depth of the groove portion 33. That is, the ratio of the total length of the grounding portion 30 in the circumferential direction to the length of the circumference where the grounding portion 30 is located (hereinafter referred to as the grounding length ratio for simplicity) is 0.55 or less. The width of the groove 33 is not increased as in the present embodiment, but the ground contact length ratio is lowered by further providing the recess 34.

If the width of the groove 33 is simply increased, the region between the grooves 33 (referred to as the leg 35) becomes smaller. When the bottle 1 is in the upright state, the leg portion 35 is in a state of supporting the bottle 1 while being deformed to some extent according to the load of the bottle 1, and the degree of deformation exceeding the deformation allowable amount of the leg portion 35 is caused. When the load of the above is applied, the leg 35 is dented or the like, but when the leg 35 is small, the deformation allowance is also reduced, and the load of the bottle is likely to cause the dent or the like when the leg 35 is stored in the warehouse. On the other hand, by providing the recess 34 that is shallower than the depth of the groove 33 without changing the width of the groove 33, the ground contact length ratio can be reduced to a small value without reducing the leg 35. Can be done. In FIGS. 11 and 12, the circumferential length d per ground contact portion 30 between the adjacent groove portion 33 and the recess 34 is approximately 2.0 mm, and the diameter of the ground contact portion 30 is 52.8 mm. The ratio of the total length of the ground contact portion 30 in the circumferential direction to the circumference length is approximately 0.19 (2.0 × 2 × 8 / (52.8 × 3.14)).

In this case, it is preferable that the ground contact length ratio is 0.3 or less. When simply increasing the width of the groove 33, there is a limit to reducing the ground contact length ratio due to restrictions due to the size of the leg 35, but a recess 34 shallower than the depth of the groove 33 is provided. By doing so, it is not necessary to reduce the size of the leg portion 35, so that the restriction due to the size of the leg portion 35 can be effectively suppressed, and the ground contact length ratio can be further reduced.

Further, it is preferable that the depth of the recess 34 is 1.5 mm or less (for example, 1.0 mm). That is, if the recess 34 is deepened, the molding reproducibility of the ground contact portion 30 deteriorates after the bottle is molded. However, according to this configuration, the depth of the recess 34 is 1.5 mm or less, so that this problem can be suitably avoided. .. In addition, in the present embodiment, the concave portion is formed in an arc shape. As a result, bottle molding can be easily performed while suitably preventing the bottle from tipping over during transportation.

(7) With respect to other configurations, it should be understood that the embodiments disclosed herein are exemplary in all respects and that the scope of the invention is not limited thereto. Those skilled in the art will be able to easily understand that modifications can be made as appropriate without departing from the spirit of the present invention. Therefore, another embodiment modified without departing from the spirit of the present invention is naturally included in the scope of the present invention.

The present invention can be used, for example, in thin-walled plastic bottles.

1 Plastic bottle (thin-walled plastic bottle)
3 Bottle body (bottle body)
23 Circumferential rib 24 Rib area 26 Flat area (smooth area)

Claims (3)

On the body of the bottle,
A panel portion having a recessed panel inside the bottle body,
The first rib area arranged on the upper side of the panel portion and
A second rib region arranged on the lower side of the panel portion is provided.
A plurality of peripheral ribs having a depth of 1.5 mm or less are formed adjacent to each other in the first rib region and the second rib region.
Mitsuru ratio of the resin amount to the delivery volume is Ri 0.017~0.041g / ml Der,
The ratio of the vertical length of the panel to the total length is 0.13 to 0.20.
A thin-walled plastic bottle having an octagonal cross-sectional shape on a surface orthogonal to the axis of the body portion provided with the panel portion. The thin-walled plastic bottle according to claim 1, wherein a smooth region is provided between the first rib region and each peripheral rib in the second rib region. The thin-walled plastic bottle according to claim 1 or 2, wherein the first rib region and the second rib region are label sticking regions.

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