JP6641781B2 - Synthetic resin container - Google Patents

Description

  The present invention relates to a synthetic resin container provided with a reduced-pressure absorption panel that absorbs a pressure change in the container after filling and sealing the contents.

  Conventionally, a synthetic resin container obtained 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 stretching blow molding, etc. It is generally used in a wide field as a container containing various beverages and the like.

When filling the contents of this type of synthetic resin container, a so-called hot pack, in which heat-sterilized contents are filled and sealed at a high temperature, is also known.
After filling and sealing the contents with a hot pack, the inside of the container cooled to room temperature is in a decompressed state, so in general, containers used for hot packs are deformed inward with cooling. A plurality of decompression absorption panels are provided along the circumferential direction on the container body to reduce the volume of the container and absorb the decrease in the internal pressure.

  On the other hand, when hot-packing the contents, the container becomes positive pressure due to the weight and heat of the contents, and furthermore, the pressure accompanying the filling (small filling pressure), so that the container is deformed so as to expand outward. The load acts on the vacuum absorption panel. Then, when the contents are hot-packed, if the decompression absorption panel is fixed in a shape that is swelled outside the container, not only can the pressure decrease in the container due to cooling not be sufficiently absorbed, There is a problem that the appearance becomes poor.

  As described above, it is considered that the decompression absorption panel is deformed inward so as to absorb a decrease in internal pressure due to cooling, but is also deformed so as to expand outward when the contents are filled. Therefore, a panel shape that allows these reversible deformations is required, and the present applicant has proposed such a panel shape in Patent Document 1.

Japanese Patent No. 4217890

  However, in the case of this type of synthetic resin container, attempts have been made to form the container as thin as possible in order to reduce its weight and cost by reducing the amount of resin used. However, in recent years, the demand for such thinning has become increasingly severe. And, as the thickness of the container becomes thinner, it becomes more difficult to uniformly deform each of the plurality of decompression absorption panels disposed on the container body. Although it is deformed in the other direction, some other decompression absorption panels can not be inverted inside the container while expanding to the outside of the container, and the tendency that the appearance becomes poor, so that it can be seen more strongly It has become to.

  In view of this, the present inventors have recently been demanding lighter and thinner containers, which have become increasingly strict, while allowing the expansion of the decompression absorption panel to the outside of the container when hot-packing, while reducing the pressure. After extensive studies on the shape of the panel in which the reduced-pressure absorbing panel can be smoothly inverted to exhibit a sufficient reduced-pressure absorbing function, the present invention was completed.

  That is, the present invention makes it possible to uniformly deform each of the plurality of decompression absorption panels provided on the container body, while preventing the reversible deformation of the decompression absorption panel while reducing the weight and thickness of the container. Accordingly, an object of the present invention is to provide a synthetic resin container provided with a reduced-pressure absorbing panel capable of exhibiting sufficient reduced-pressure absorbing performance without causing appearance defects.

  The synthetic resin container according to the present invention is a synthetic resin container including a mouth, a shoulder, a trunk, and a bottom, and the trunk includes a plurality of decompression absorption panels disposed along a circumferential direction. There, the decompression absorption panel, a central portion extending along the height direction in the circumferential central portion, two located on both sides of the central portion, curved along the circumferential direction from the central portion side A panel body having a panel dividing portion, and each of the panel dividing portions has a plurality of transverse grooves extending in a circumferential direction from one end of the panel dividing portion on the central portion side to the other end, in a height direction. Are arranged along the line.

  Advantageous Effects of Invention According to the present invention, it is possible to uniformly deform each of a plurality of decompression absorption panels disposed along a circumferential direction on a container body, and to exhibit sufficient decompression absorption performance without causing appearance defects. it can.

It is a front view showing the outline of the container made of a synthetic resin concerning the embodiment of the present invention. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. It is CC sectional drawing of FIG. It is explanatory drawing which shows the change of the circumferential direction of the decompression absorption panel before and behind a hot pack typically, (a) shows the state before a hot pack, (b) expands outside a container at the time of a hot pack. It shows the state of the error. It is explanatory drawing which shows the outline of the modification of the synthetic resin container which concerns on embodiment of this invention.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  In the present embodiment, the container 1 is formed into a cylindrical preform having a bottom by, for example, injection molding or compression molding using a thermoplastic resin. It 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 as shown.

  In manufacturing such a container 1, as the 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, and those blended with these resins or other resins are preferable. It is. In particular, an ethylene terephthalate-based thermoplastic polyester such as polyethylene terephthalate is preferably used. Further, acrylonitrile resin, polypropylene, propylene-ethylene copolymer, polyethylene and the like can also be used.

The mouth 2 is a cylindrical portion having an annular fitting projection 21 to which a lid (not shown) is attached. In the present embodiment, an example is shown in which the lid is attached to the mouth 2 by fitting of the concave and convex shapes to each other, but the lid may be attached to the mouth 2 by screwing. The mouth portion 2 includes a portion having substantially the same diameter immediately below a support ring 22 generally formed in a container of this type, and has a frustoconical shoulder portion expanding in diameter toward the body portion 4. It is connected to 3.
FIG. 2 shows a cross section taken along the line AA in FIG. 1, but the thickness of a portion of the mouth portion 2 below the support ring 22 is omitted. Also, in FIG. 3 showing a cross section taken along the line BB in FIG. 1, and in FIG. 4 showing a cross section taken along the line CC in FIG. 1, the thickness is similarly omitted.

The body 4 is a portion that occupies most of the height direction of the container 1, and the upper end is connected to the shoulder 3, and the lower end is connected to the bottom 5. On the peripheral surface of the body 4, six decompression absorption panels 6 are disposed at predetermined intervals along the circumferential direction, and are orthogonal to the height direction of the portion where the decompression absorption panel 6 is disposed. The cross-sectional shape is hexagonal (see FIG. 3).
The container 1 having such a body 4 has a so-called round bottle-like container shape in which the cross-sectional shape is rounded as a whole.

  In the present embodiment, by providing a horizontal bead 43 extending in an annular shape along the circumferential direction on the upper end side and the lower end side of the body 4, the horizontal direction (the direction orthogonal to the height direction) is provided. ), The lateral bead 43 can be omitted as appropriate.

  Here, the height direction refers to a direction perpendicular to the horizontal plane when the container 1 is erected on a horizontal plane with the mouth 2 up, and in this state, the vertical, horizontal, and vertical directions of the container 1 Shall be stipulated.

In the present embodiment, the decompression absorption panel 6 has a vertically long rectangular shape, and has a frame portion 60 that is depressed inward from the periphery thereof to form a step, and a panel main body 61 that is connected to the frame portion 60. are doing.
The panel main body 61 has a central portion 62 extending in the height direction at a central portion in the circumferential direction, and two panel divisions located on both sides of the central portion 62 and curved along the circumferential direction from the central portion 62 side. And a portion 63. In each of the panel divisions 63, a plurality of transverse grooves 65 extending in the circumferential direction from one end of the panel division 63 on the central part 62 side to the other end are arranged in a row in the height direction. .

Since the decompression absorption panel 6 has the panel main body 61 having such a panel shape, when the contents are hot-packed, the panel main body 61 is moved to the upper and lower edge sides as shown by a chain line in FIG. The starting groove is curved so as to bulge outward from the container, and at this time, the transverse groove 65 is expanded. As a result, the panel dividing portion 63 is deformed such that its length in the height direction is extended, and a sufficient amount of deformation can be secured. Then, with such deformation in the height direction, as shown in FIG. 5B, the panel main body 61 is also deformed so as to be entirely curved in the circumferential direction, so that the container 1 expands outward. It is possible to easily absorb the load that is going to be deformed.
Then, at the time of decompression, the panel body 61 can be smoothly inverted from a state swelling outwardly of the container due to the elastic restoring force of the expanded transverse groove 65, and the reversible deformation of the decompression absorption panel 6 Can be unimpeded.

  In FIG. 4, the solid line is a state before the hot pack, and how the reduced-pressure absorption panel 6 is deformed in the height direction when the hot pack is performed is schematically shown by a chain line. Is shown. FIG. 5 is an enlarged view of a portion surrounded by a chain line in FIG. 3 to schematically show how the reduced-pressure absorption panel 6 is deformed in the circumferential direction. FIG. FIG. 5 (b) shows a state before packing, and FIG. 5 (b) shows a state where the container swells outward when hot-packed.

  As described above, according to the present embodiment, while allowing the expansion of the decompression absorption panel 6 to the outside of the container at the time of hot-packing the contents, the container is cooled to room temperature and the pressure in the container is reduced. Occasionally, the reduced-pressure absorption panel 6 bulging outward from the container can be smoothly inverted. For this reason, while reducing the weight and thickness of the container 1, the plurality of decompression absorption panels 6 arranged along the circumferential direction on the body 4 without hindering the reversible deformation of the decompression absorption panel 6. By deforming each of them evenly, it is possible to exhibit sufficient reduced pressure absorption performance without causing appearance defects.

It is preferable that the transverse groove portions 65 be arranged in rows at an interval I of 5 to 20 mm along the height direction so that such an effect is favorably exhibited.
If the thickness is less than the above range, the shape of the panel dividing portion 63 between the transverse groove portions 65 tends to be inferior. On the other hand, if it exceeds the above range, there is a tendency that when the panel dividing portion 63 is deformed inwardly of the container with cooling, it is deformed non-uniformly.

The width W _TG of the groove bottom of the transverse groove 65 is preferably in the range of 0.5 to 2.0 mm.
If the thickness is less than the above range, when an impact (for example, a drop impact) is applied to the container 1, whitening due to cohesive failure occurs at the groove bottom of the transverse groove 65, which tends to impair the appearance. On the other hand, if the thickness exceeds the above range, the thickness of the groove bottom portion of the transverse groove 65 cannot be sufficiently reduced at the time of blow molding. There is a tendency that deformation of the portion 63 in the height direction is suppressed.

The depth D _TG of the transverse groove 65 (the difference in height between the surface of the panel dividing portion 63 and the bottom of the transverse groove 65) is preferably in the range of 0.5 to 1.5 mm.
If the thickness is less than the above range, the spread of the transverse groove 65 during hot pack becomes small, and there is a tendency that the deformation amount of the panel dividing portion 63 at that time cannot be sufficiently secured. On the other hand, if the above range is exceeded, the panel is divided from a virtual arc line formed by a radius connecting the upper end or lower end and the center of the container in a cross section at the upper end or lower end of the frame portion 60 of the decompression absorption panel 6. The part 63 tends to protrude outside the container.

  In the present embodiment, the above numerical ranges and the like are set by taking the container 1 having a capacity of 500 ml as an example, and these numerical values can be appropriately adjusted according to the capacity of the container 1.

  In the present embodiment, the transverse groove portion 65 may have a straight cross-sectional shape at the bottom of the groove, or may be gently curved so as to protrude inward or outward of the container. The transverse groove 65 is preferably provided so as to cross the panel division 63 orthogonally to the height direction from one end to the other end of the panel division 63 on the side of the central part 62, There may be.

In the present embodiment, the arrangement of the transverse grooves 65 arranged in the panel dividing portion 63 is not limited, but one of the plurality of transverse grooves 65 is most likely to be located outside the container when hot-packing the contents. It is preferable to arrange the panel body 61 at the center in the height direction of the panel body 61 which tends to swell greatly.
In addition, the transverse grooves 65 are vertically symmetrical (including substantially symmetric) about the center in the height direction of the panel main body 61 so that the panel main body 61 can be deformed in a balanced manner in the height direction. Preferably, they are arranged.

  In particular, in the present embodiment, by combining these arrangements, as shown in FIG. 1, the number of arrangement of the transverse groove portions 65 arranged in the panel division portion 63 is odd (5 in the example shown in FIG. 1). The transverse groove 65 is positioned at the center of the panel body 61 in the height direction, and the transverse groove 65 is evenly arranged in the height direction so as to be vertically symmetrical about the center of the panel body 61 in the height direction. It is preferable to arrange them in rows. Furthermore, one panel division 63 and the other panel division 63 are symmetric (left-right symmetric) with the central part 62 as the axis of symmetry so that the panel main body 61 can be deformed in a well-balanced manner even along the circumferential direction. It is preferable to arrange the transverse groove portions 65 in a row, and by arranging the transverse groove portions 65 in a more symmetrical arrangement, the panel body 61 can be deformed in a more balanced manner.

  Further, in the example shown in FIG. 1, the panel dividing portion 63 is located within the container from the virtual arc line formed by the radius connecting the lower end and the center of the container in the cross section at the lower end of the frame portion 60 of the reduced-pressure absorbing panel 6. It is curved so as to bulge outward from the container along the circumferential direction from the central portion located on the side (see FIG. 3). By doing so, the amount of deformation when the decompression absorption panel 6 is deformed inwardly of the container is increased, and the decompression absorption performance is enhanced. May be swollen. At this time, the cross-sectional shape of the panel dividing portion 63 is appropriately designed in consideration of the opening of the blow molding die.

  Further, in consideration of increasing the amount of deformation when the decompression absorption panel 6 is deformed inward of the container to enhance the decompression absorption performance, the entire panel dividing portion 63 is directed toward the center in the height direction. It is preferable that the projections gradually extend outward from the container.

  Further, in the example shown in FIG. 1, the central portion 62 extending along the height direction at the central portion in the circumferential direction of the panel main body 61 is formed in a U-shape so that its cross-sectional shape is convex outside the container. It is formed as a protruding ridge. By forming the central portion 62 as such a ridge, it can be a guiding portion when the decompression absorption panel 6 expands outside the container. Further, the central portion 62 may be formed as a ridge protruding in a U-shape so that its cross-sectional shape is convex inward of the container. Serves as a guiding part when deforming inward of the container. Whether the central portion 62 is convex toward the outside of the container or convex toward the inside of the container is appropriately determined depending on whether it is easy to swell outside the container of the reduced-pressure absorption panel 6 or easily deform inside the container. The central portion 62 is not limited to the U-shape, and may be formed in a V-groove shape, a trapezoid shape, or the like.

  In addition, in consideration of increasing the amount of deformation when the decompression absorption panel 6 is deformed inwardly of the container to enhance the decompression absorption performance, the central portion 62 is formed to project outward or inwardly of the container. Preferably, it is gently curved along the height direction.

  In addition, in the transfer step when hot-packing the contents, the panel main body 61 is placed at the upper end or the lower end of the frame portion 60 of the reduced-pressure absorption panel 6 so that the panel main body 61 does not rub against other containers or transfer devices. In the cross section, it is preferable that the panel main body 61 fits within a virtual arc line formed by a radius connecting the upper end or the lower end to the center of the container.

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

For example, in the above-described embodiment, an example is described in which six reduced pressure absorbing panels 6 are provided in the container body 4, but the present invention is not limited to this. When the present invention is applied to a round bottle-shaped synthetic resin container, the number of panels of the reduced-pressure absorption panel 6 can be appropriately selected from a range of four to eight.
Further, in the above-described embodiment, an example was described in which the shape of the reduced-pressure absorption panel 6 was a vertically long rectangular shape. However, the present invention is not limited to this, and may be a vertically long oval shape.

  In the above-described embodiment, an example in which the present invention is applied to a round bottle-shaped synthetic resin container has been described. However, the present invention relates to a so-called square shape having a rectangular or rectangular cross-sectional shape. The present invention can also be applied to a bottle-shaped container made of synthetic resin.

When applied to a square bottle-shaped container made of synthetic resin, the decompression absorption panel 6 may be provided with four decompression absorption panels 6 along the circumferential direction on the four body side surfaces. Is a rectangular bottle-shaped synthetic resin container, for example, as shown in FIG. 5, the decompression absorption panel 6 of the present invention is provided only on two opposing surfaces on the long sides thereof, and A decompression absorption panel having another panel shape can be provided on the two sides of the side. In any case, by arranging the decompression absorption panel 6 in the present invention on the container body 4 along the circumferential direction, the decompression absorption panel 6 is uniformly deformed, and sufficient decompression is performed without causing appearance defects. It can exhibit absorption performance.
6A and 6B are explanatory views schematically showing the above-described modification, in which FIG. 6A is a front view and FIG. 6B is a side view.

  The present invention as described above can be applied to a synthetic resin container provided with a reduced pressure absorption panel that absorbs a pressure change in the container after filling and sealing the contents.

DESCRIPTION OF SYMBOLS 1 Container 2 Mouth 3 Shoulder 4 Body 5 Bottom 6 Decompression absorption panel 61 Panel main body 62 Center 63 Panel division 65 Crossing groove

Claims (9)

A synthetic resin container having a mouth, a shoulder, a body, and a bottom, wherein the body has a plurality of reduced-pressure absorption panels disposed along a circumferential direction,
The decompression absorption panel has a central portion extending along a height direction at a circumferential central portion, and two panel dividing portions located on both sides of the central portion and curved along the circumferential direction from the central portion side. And a panel body comprising:
In each of the panel divisions, a plurality of transverse grooves extending circumferentially from one end of the panel division on the central portion side to the other end are arranged in a row along the height direction. Synthetic resin container.   The synthetic resin container according to claim 1, wherein the panel division portion swells outward of the container.   3. The synthetic resin container according to claim 1, wherein the transverse groove portions are arranged in rows at intervals of 5 to 20 mm along the height direction. 4.   The synthetic resin container according to any one of claims 1 to 3, wherein a depth of the transverse groove portion is 0.5 to 1.5 mm.   The synthetic resin container according to any one of claims 1 to 4, wherein a cross-sectional shape of the central portion is convex outside the container or inside the container.   The synthetic resin container according to any one of claims 1 to 5, wherein the transverse groove portions are arranged in an array such that one of the transverse groove portions is located at the center in the height direction of the panel body.   The synthetic resin container according to any one of claims 1 to 6, wherein the transverse groove portions are arranged so as to be vertically symmetrical with respect to a center in the height direction of the panel body.   The number of arrangement of the transverse groove portions arranged in the panel division portion is an odd number, and the middle transverse groove portion is located at the center in the height direction of the panel main body, and the transverse groove portions are evenly distributed along the height direction. The synthetic resin container according to any one of claims 1 to 7, which is arranged in a line.   The synthetic resin container according to any one of claims 1 to 8, wherein the transverse groove portions are arranged so as to be symmetrical with respect to the center portion as a symmetric axis.