JP7202537B2 - plastic bottle - Google Patents

Description

The present invention relates to plastic bottles. More particularly, it relates to plastic bottles such as those for beverages that are heated in hot warmers or vending machines.

In recent years, plastic bottles have been used for hot beverages.
Such plastic bottles increase the internal pressure of the bottle when heated. At this time, it is required that there is no significant difference in the shape of the bottle before and after heating. After further heating, when cooled, the internal pressure of the bottle decreases. Even in this case, it is required that there is no significant difference in the shape of the bottle before and after cooling.
For example, Patent Literature 1 discloses a heating plastic bottle in which a concave panel portion having a pressure absorbing function is formed on the cylindrical surface of the body portion.

Japanese Unexamined Patent Application Publication No. 2011-31899

The provision of a concave pressure-absorbing panel on the body of a plastic bottle reduces the volume of the body of the bottle and imposes constraints on the design of the bottle.
Also, a plastic bottle may be attached with a shrink label or a roll label as a surface decoration. In the case of a roll label, one end of a strip-shaped label is glued to a predetermined position on the body of the bottle, and the label is wound around the bottle. be.
If a pressure-absorbing panel is provided in the portion of the body of the bottle where the roll label is attached, the pressure-absorbing panel and the uneven structure of the pillars located between the pressure-absorbing panel walls allow the label to adhere to the bottle. There is a problem that the fixing position is limited to the columnar portion.
In addition, if a pressure absorbing panel is provided at the portion where the shrink label or roll label is attached, the display portion of the label will look distorted due to the uneven structure, which impairs the aesthetic appearance of the bottle. .
Moreover, since the plastic bottle is transparent and the state inside can be confirmed, a see-through label or the like is sometimes attached to the bottle. However, when the body is provided with a pressure absorbing panel, the inside looks distorted, which impairs the aesthetics of the bottle.

The present invention has been made in such a situation, and its object is to provide a bottle body without a pressure-absorbing panel, without restricting the bottle mounting surface of the roll label and improving the aesthetics of the bottle. To provide a plastic bottle which is excellent and maintains a good bottle appearance both during heating and during cooling after heating.

A plastic bottle of the present invention for solving the above problems comprises a mouth, a body, and a bottom, the body having a cylindrical shape with a cylindrical surface, and the body having a cylindrical surface. The portion is characterized by having an annular stepped portion that expands and contracts in the axial direction.

Moreover, the plastic bottle of the present invention may be a warming plastic bottle.

According to the plastic bottle of the present invention, even if there is no pressure absorbing panel in the body of the bottle, the bottle mounting surface of the roll label is not restricted, and the aesthetic appearance of the bottle is excellent. It is possible to provide a plastic bottle that maintains a good bottle appearance at any time of cooling.

BRIEF DESCRIPTION OF THE DRAWINGS It is a front view which shows an example of embodiment of the plastic bottle concerning this invention. FIG. 2 is a plan view of the plastic bottle of FIG. 1; 1 is a front view showing an example of an embodiment of a plastic bottle according to Comparative Example 1. FIG. FIG. 10 is a front view showing an example of an embodiment of a plastic bottle according to Comparative Example 2;

An example of an embodiment of the plastic bottle of the present invention will be described below with reference to the drawings. The present invention is not limited to the following embodiments, and various modifications can be made within the scope of the gist of the present invention.

First, the outline of the plastic bottle according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. In this specification, the terms "upper", "lower", "vertical" and "circumferential" respectively refer to the upward, downward, vertical and horizontal directions when the plastic bottle 100 is upright (FIG. 1). It means direction.

The plastic bottle 100 shown in FIGS. 1 and 2 includes a mouth portion 1, a shoulder portion 2 provided below the mouth portion 1, a body portion 3 provided below the shoulder portion 2, and a a bottom portion 4;
A label 20 is provided on the outside of the plastic bottle. Note that the label 20 is indicated by a dashed line in FIG.

Among them, the trunk portion 3 has a cylindrical surface, and has a substantially cylindrical shape as a whole. Here, the barrel diameter indicates the outer diameter. The thickness of the body is preferably 0.1 mm or more and 0.5 mm or less.

The cylindrical surface of the body portion 3 is provided with a stepped portion 10 that expands and contracts in the axial direction. The stepped portion 10 has an outer peripheral surface with a smaller diameter than the outer peripheral surface of the body portion 3 . The stepped portion 10 is formed in an annular shape continuously in the circumferential direction.
In this embodiment, the stepped portion 10 is formed at the connecting portion between the body portion 3 and the shoulder portion 2 and the connecting portion between the body portion 3 and the bottom portion 4 .
Further, the body portion 3 is formed with an attachment area 21 to which an adhesive material for attaching the label 20 is attached. In the present embodiment, the attachment region 21 is formed on a region where the stepped portion 10 is not formed, that is, on a cylindrical surface.

The number of stepped portions 10 is not limited to two, and may be one or more. However, if there are many steps, the cylindrical surface of the body 3 becomes narrower, and the attachment area 21 also becomes narrower. preferable.
Moreover, in the present embodiment, all the stepped portions 10 have the same shape and dimensions. However, it is not limited to this, and the shapes or dimensions of all the stepped portions 10 may not necessarily be the same.

The stepped portion 10 extends over the entire circumferential direction. The stepped portion 10 is elastically deformed when heated, and the trunk portion is elongated in the vertical direction, thereby exhibiting the function of absorbing pressure.
On the other hand, the stepped portion 10 is elastically deformed during cooling after heating, and the trunk portion is in a state of being bent in the vertical direction, thereby exhibiting the function of absorbing reduced pressure.

Further, the depth d1 (see FIG. 2) of each stepped portion 10 is 1.0 mm to 4.0 mm. If the depth d1 of each stepped portion 10 is less than 1.0 mm, it is difficult to obtain the effect of flexibility and elasticity. Hard to get. On the other hand, if the depth d1 of each stepped portion 10 exceeds 8.0 mm, the stepped portion 10 will be whitened due to poor shaping or overstretching during blow molding. The depth d1 of the stepped portion 10 means the maximum distance from the cylindrical surface 14 to the bottom surface 13 of each stepped portion 10 (see FIG. 2).

Further, in FIG. 1, if the total height of the body is h3 and the height from the top of the uppermost stepped portion 10A to the lower portion of the lowest stepped portion 10B is h4, the shorter the height h4, the narrower the range where the roll label is provided. Since the object of the present invention cannot be achieved, the height h4 is preferably 2/3 or more of the total height h3 of the trunk, and more preferably the height h4 is 3/4 or more of the height h3.

The size of such a plastic bottle 100 is not limited, and any size bottle may be used. For example, the volume of the plastic bottle 100 may be 200ml-600ml. In particular, when the total height h2 (see FIG. 1) of the container is 120 mm to 210 mm and the trunk diameter w3 (see FIG. 1) of the container is 52 mm to 75 mm, the effects of the present embodiment can be preferably obtained. .

In this embodiment, as described above, the depth d1 of each stepped portion is set to 1.0 mm to 4.0 mm. As a result, even when the plastic bottle 100 is formed particularly thin, the appearance of the bottle can be maintained well both during heating and during cooling after heating. Specifically, the average wall thickness of the plastic bottle 100 can be reduced to 0.20 mm to 0.54 mm. The average wall thickness of the plastic bottle 100 is "average wall thickness" = "weight of plastic bottle 100 (excluding mouth portion 1)"/{"surface area of plastic bottle 100 (excluding mouth portion 1)" x " Specific gravity of plastic material (1.335 for PET)}}.

Such a plastic bottle 100 can be produced by biaxially stretching blow molding a preform produced by injection molding a synthetic resin material. As the material for the preform, that is, the plastic bottle 100, it is preferable to use a thermoplastic resin, particularly PE (polyethylene), PP (polypropylene), PET (polyethylene terephthalate), and PEN (polyethylene naphthalate).

The plastic bottle 100 can also be formed as a multi-layer molded bottle with two or more layers. That is, by extrusion molding or injection molding, for example, the intermediate layer is made of MXD6, MXD6 + fatty acid salt, PGA (polyglycolic acid), EVOH (ethylene vinyl alcohol copolymer), PEN (polyethylene naphthalate), or the like to provide gas barrier properties and light shielding properties. A multi-layered bottle having gas barrier properties and light shielding properties may be formed by extrusion molding a preform comprising three or more layers as the resin (intermediate layer), followed by blow molding. It is preferable that such an intermediate layer is provided at least inside the body portion 3 of the plastic bottle 100 . In addition, it is preferable to provide an intermediate layer in a region of the bottom portion 4 excluding the central portion thereof. This is because there is a risk of delamination (delamination) at this portion when receiving an impact such as when the case is dropped. In order to have gas barrier properties and light shielding properties, a blend bottle may be formed by blending thermoplastic resins in addition to forming a multi-layered bottle.

Next, the label 20 will be explained.
The label 20 displays the contents, etc., and is attached to the outer surface of the plastic bottle 100 . This label 20 may be produced, for example, by forming a sheet-like film into a cylinder and pasting the ends thereof. The label 20 is adhered to the plastic bottle 100 by an adhesive material attached to the affixing area 21 . The label 20 is provided over the entire length of the plastic bottle so as to surround it, and has a substantially circular horizontal cross section.

In this case, the label 20 is provided so as to cover the body portion 3 of the plastic bottle 100 , but may be provided on the entire area or a partial area other than the mouth portion 1 . For example, label 20 may be provided to cover shoulder 2 , body 3 and bottom 4 . Alternatively, the label 20 may be provided so as to cover the shoulder portion 2 and the torso portion 3 . Furthermore, the number of labels 20 is not limited to one, and a plurality of labels may be provided.

Examples of the label 20 include a roll label, a tack label, a paper label, and the like. Among these, it is preferable to use a roll label from the viewpoint of productivity.
As the label 20, for example, a shrink label or stretch label that does not use an adhesive material may be used.

Next, the operation of this embodiment having such a configuration will be described.

First, the plastic bottle 100 is filled with liquid such as green tea or coffee, and then sealed. Furthermore, a shrink label or a roll label is attached around the body portion 3 . The plastic bottle 100 is then sold in a heated state in a hot warmer or vending machine.

At this time, by heating the plastic bottle 100, the liquid content is also heated, and the volume of the liquid content increases. As a result, the internal pressure of the plastic bottle 100 is increased. Further, the step portion 10 is elastically deformed due to an increase in the bottle internal pressure of the plastic bottle 100 .

In this case, each stepped portion 10 of the body portion 3 is elastically deformed during heating, and the stepped portion 10 of the body portion is elongated in the vertical direction. In the present embodiment, the depth d1 of each stepped portion 10 is set to 1.0 mm to 4.0 mm, one at each of the connecting portion between the shoulder portion 2 and the trunk portion 3 and the connecting portion between the trunk portion 3 and the bottom portion 4. there is Since the depth d1 of each stepped portion 10 is set to 1.0 mm to 4.0 mm in this way, even if each stepped portion 10 is elastically deformed due to an increase in the internal pressure of the bottle, each stepped portion 10 will not move from the cylindrical surface 14. It does not protrude outward. Also, the position of the label is almost the same. As a result, the appearance of the bottle can be well maintained during heating.
In addition, the buckling strength can be increased by forming the stepped portions 10 at the connecting portion between the shoulder portion 2 and the trunk portion 3 and at the connecting portion between the trunk portion 3 and the bottom portion 4 .

On the other hand, it is also conceivable that the heated plastic bottle 100 is left unopened at room temperature and cooled. When the bottle is cooled after being heated in this manner, the volume of the content is reduced, and the internal pressure of the plastic bottle 100 is reduced.

In this case, the stepped portion 10 elongated in the vertical direction is elastically deformed by being heated, and the stepped portion 10 of the trunk portion 3 is contracted in the vertical direction. For this reason, in the present embodiment, when the bottle internal pressure is reduced and each stepped portion 10 is elastically deformed and contracted in the vertical direction of the stepped portion 10, since the stepped portion 10 is annular, the decompression amount is reduced. Since it absorbs evenly, the body part 3 does not collapse locally. Moreover, since the stepped portion 10 is arranged inside the label, the contracted stepped portion 10 is inconspicuous in appearance. In addition, by arranging the stepped portion 10 at the connecting portion between the shoulder portion 2 and the body portion 3 and the connecting portion between the body portion 3 and the bottom portion 4, the load in the axial direction of the container can be reduced even if the internal pressure of the bottle is reduced. In contrast, elastic deformation in the vertical direction is facilitated. Therefore, even when the plastic bottle 100 is cooled after being heated, the appearance of the bottle can be maintained in good condition.

By the way, after the plastic bottle 100 is filled with contents, the plastic bottle 100 is sold as a product after affixing a label indicating the contents and the like. In this case, the label 20 is adhered to the plastic bottle 100 by the adhesive material applied to the application area 21 . Here, in the plastic bottle 100, the sticking area 21 is formed in an area where the stepped portion 10 is not formed, that is, on the cylindrical surface. As a result, when the label 20 is attached to the plastic bottle 100, it is possible to prevent the adhesive material from entering the stepped portion 10, making it difficult to attach the label.

As described above, according to the present embodiment, the depth d1 of each stepped portion 10 is set to 1.0 mm to 4.0 mm, and it is configured to be expandable in the axial direction. A good appearance of the bottle can be maintained at any time of cooling. In particular, even when the bottle is made thin (for example, when the average wall thickness is 0.20 mm to 0.54 mm), it is possible to maintain a favorable appearance of the bottle.

Further, in this embodiment, the label 20 is adhered to the plastic bottle 100 with the adhesive applied to the labeling area 21 . Here, in the plastic bottle 100, the sticking area 21 is formed in an area where the stepped portion 10 is not formed, that is, on the cylindrical surface. As a result, it is possible to prevent the problem of difficulty in attaching the label 20 . Therefore, a highly productive roll label can be easily attached as the label 20 .

Further, according to the present embodiment, the plastic bottle 100 can be composed of either a heat-resistant bottle or a non-heat-resistant bottle. That is, since an aseptic filling method can be adopted as a filling method for the liquid content, it is possible to reduce the production cost without impairing the flavor of the liquid content in the bottle.

Next, a specific example of this embodiment will be described.

First, the following three types of plastic bottles (Example 1, Comparative Example 1, and Comparative Example 2) were produced. It was a plastic bottle made from a PET resin preform by biaxial stretching blowing, and its weight was 22 g.

(Example 1)
A 295 ml plastic bottle 100 (Example 1) having the configuration shown in FIGS. 1 and 2 was produced. In this case, the stepped portion 10 was formed in two ring-shaped portions, one at the connection portion between the portion 2 and the body portion 3 and the other at the connection portion between the body portion 3 and the bottom portion 4 .

Further, in this plastic bottle 100 (Example 1), the depth d1 of each stepped portion 10 is 2.5 mm, the total height h3 of the body portion is 88.7 mm, and the distance from the top of the top stepped portion 10A to the bottom of the bottom stepped portion 10B is 88.7 mm. The height h4 of the container was 78.8 mm, the total height h2 of the container was 132 mm, the barrel diameter w3 was 66 mm, and the full filling capacity was 310 ml.

(Comparative example 1)
Next, a 280 ml plastic bottle 50 (comparative example 1) having the configuration shown in FIG. 3 was produced. As shown in FIG. 3 , the plastic bottle 50 (comparative example 1) has a mouth portion 51 , a shoulder portion 52 , a body portion 53 and a bottom portion 54 . Six panel portions 56 are formed on the cylindrical surface of the body portion 53 . In this case, the depth of the deepest portion of each panel portion 56 was 2.2 mm.

In this plastic bottle 50 (Comparative Example 1), the height h3 of each panel portion 56 is 50 mm, the width w4 of each panel portion 56 is 25 mm, the total height h4 of the container is 132 mm, the barrel diameter w5 is 66 mm, and the full filling capacity is 293 ml, and the width w6 of each columnar portion 57 was 4.2 mm.

(Comparative example 2)
Next, a plastic bottle 60 for 300 having the configuration shown in FIG. 4 (Comparative Example 2) was produced. As shown in FIG. 4 , a plastic bottle 60 (comparative example 2) has a mouth portion 61 , a shoulder portion 62 , a body portion 63 and a bottom portion 64 . A panel portion is not formed on the cylindrical surface of the body portion 63 . The container had a total height h4 of 132 mm, a barrel diameter w5 of 66 mm, and a full filling capacity of 314 ml.

Four of each of the above three types of plastic bottles (Example 1, Comparative Example 1, and Comparative Example 2) were each attached with a roll label, filled with water as the content liquid, and then sealed. After that, three types of plastic bottles (Example 1, Comparative Example 1, and Comparative Example 2) were each immersed in hot water at 75°C for 1 hour to a position 100 mm from the bottom of the container, and the states of the bottles after heating were compared. bottom.

As a result, four out of the four plastic bottles 100 of Example 1 maintained an upright posture and maintained a good bottle appearance. Moreover, the average of the total height increase was 6.5 mm. Furthermore, even after the bottle was cooled to room temperature, the appearance of the bottle was well maintained.

On the other hand, four out of the four plastic bottles 50 of Comparative Example 1 maintained an upright posture and maintained a good bottle appearance. Moreover, the average of the total height increase was 4.3 mm. Furthermore, even after the bottle was cooled to room temperature, the appearance of the bottle was well maintained.
Thus, in Comparative Example 1, there is no problem in the heating performance, but the bottle attachment surface of the roll label is limited to the columnar portion between the panels.

In addition, since the plastic bottle 60 of Comparative Example 2 had an insufficient pressure absorbing function, two of the four bottles did not maintain an upright state, and the appearance of the bottle was spoiled. The average total height increase of the two bottles that were in the upright state was 6.1 mm.

From this, the plastic bottle 100 according to the present embodiment (Example 1) has a larger change in overall height (elongation in the vertical direction) than the bottles of Comparative Examples 1 and 2. It was confirmed that the appearance of the bottle was well maintained during cooling.
In addition, in the plastic bottle 100 according to the present embodiment (Example 1), the bottle mounting surface of the roll label was not limited as compared with the bottle of Comparative Example 1, and the label could be easily attached.

1, 51, 61 Mouth 2, 52, 62 Shoulder 3, 53, 63 Body 4, 54, 64 Bottom 10 Step 10A Top step 10B Bottom step 13 Bottom 14 Cylindrical surface 20 Label 21 Attachment area 56 Panel part 57 Columnar part 50, 60, 100 Plastic bottle

Claims (2)

In a plastic bottle to which a label is affixed,
a mouth;
a torso;
a bottom and a
the body has a cylindrical shape with a cylindrical surface without pressure-absorbing panels ;
The body portion has an annular stepped portion that expands and contracts in the axial direction, and the stepped portion is arranged in the region where the label is arranged in both the vertical direction and the circumferential direction,
A plurality of affixing areas to which an adhesive material for affixing the label is affixed is formed on the body,
The pasting area is formed in an area where the stepped portion is not formed ,
a cylindrical surface on which the stepped portion is not formed between the adjacent pasting regions;
The stepped portion has a depth of 1.0 mm or more and 4.0 mm or less,
A plastic bottle , wherein the wall thickness of the body is 0.1 mm or more and 0.5 mm or less . The plastic bottle has a volume of 200 ml or more and 600 ml or less,
The plastic bottle has a height of 120 mm or more and 210 mm or less,
2. The plastic bottle according to claim 1, wherein said plastic bottle has a trunk diameter of 52 mm or more and 75 mm or less .

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