JP2012116516A - Delamination container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a delamination container which, even when bottom breakage occurs, can maintain the influence to the minimum range in a relative simple structure and can maintain a function as a lamination container.SOLUTION: In the delamination container 1 in which a container body is blow-molded by an outer layer 2 and an inner layer 3 having low compatibility with the outer layer, a bottom part 7 under the container body is formed by inverting a bottom wall 9A molded in a state of being swollen to the outer side around an annular bottom end wall 8 located between the barrel part 4 of the container body and a bottom wall 9B, and such a non-delamination part 20 that a part of the bottom wall 9B is press-fixed to the inner wall of a barrel part lower end side by the inversion is disposed.

Description

  The present invention relates to a delamination container in which an inner layer is detachably laminated on an outer layer. More specifically, the present invention relates to a delamination container obtained by blow molding in a so-called delami bottle, which is formed by laminating a flexible bag-like inner layer on an outer layer having a self-shape retaining ability.

  In addition to laminating the inner layer in close contact with the inner surface of the outer layer, and providing air intake holes on the outer layer side to introduce air between the inner and outer layers, air is introduced between the inner and outer layers, thereby adding to the contents in the inner layer. A delamination container designed to prevent direct contact with air is known. Such a delamination container is generally called a delami bottle.

The delamination container can be obtained by blow molding using a mold. Specifically, an outer layer parison and an inner layer parison having low compatibility are coextruded to form a laminated parison, and the laminated parison is blow-molded to obtain a laminated peeling container. However, the bottom seal part of the container that is crushed and formed by the pinch-off part of the mold for blow molding (sometimes referred to as the pinch-off or pinch-off part of the container) is an outer layer having low compatibility with each other as described above. Since it has a laminated structure (also referred to as a polymerization pressure-bonding structure) consisting of a portion and an inner layer portion, it is easy to peel off, and there is a concern that it will easily crack when receiving an unexpected impact.
If a bottom crack occurs, outside air flows from the cracked portion, and if moisture is contained in the outside air, inconveniences such as moisture remaining at the bottom of the container are caused. In addition, when the laminated peeling container is adopted as a squeeze specification, the air that has flowed from the peeling part once flows out when the container is gripped, so the squeeze function of the container does not work sufficiently, and the contents The inconvenience that it becomes difficult to discharge the object occurs, and the reliability of the container is lowered.

  Therefore, various proposals have conventionally been made regarding the prevention of bottom cracks caused by the peeling of the inner and outer layers in the laminate peeling container. For example, Patent Document 1 discloses a laminated peeling container in which a peeling restricting portion in which both inner and outer layers are bent outward is provided at the lower portion of the container body to prevent damage to the bottom seal portion.

JP 2009-12786 A

The peeling restricting portion according to the cited document 1 has a structure in which an upward force is applied to the body portion at the bottom of the container body after normal molding to bend and bulge outward, and the bent portion of the inner layer is sandwiched between the bent portions of the outer layer. Yes.
However, in order to provide the bent peeling regulating portion, a crushing process for further crushing the molded container is necessary. In addition, it is necessary to prepare equipment for performing this crushing process, and to give sufficient consideration to the crushing conditions and device control.

  The object of the present invention is a relatively simple structure, and even if a bottom crack occurs, the effect is kept to the minimum range and the function as a laminated container is maintained, and it is durable that can be used continuously. A delamination container is proposed.

An object of the present invention is a delamination container in which a container body is blow-molded with an outer layer and an inner layer having low compatibility with the outer layer,
A bottom wall formed so that a bottom portion of the container body bulges outward is formed by inverting an annular bottom end wall positioned between the body portion of the container body and the bottom wall. And a non-peeling portion in which a part of the bottom wall is pressure-bonded to the inner wall on the lower end side of the body portion by the reversal.

  Further, a constricted portion having a reduced diameter is formed on the lower end side of the body portion, and the lower side of the constricted portion is a skirt-shaped inclined surface that increases in diameter toward the outside. The lower end may be continuous with the annular bottom end wall, and the inverted bottom wall may be pressed against the inner wall inside the inclined surface to form the non-peeling portion.

Further, the bottom wall formed in the bulging state is a dome shape that bulges downward from the container main body, and includes an annular groove portion in the middle position of the dome shape,
The container may be formed by inverting a region between the annular groove and the annular bottom end wall.
The bottom end wall is preferably formed to be thinner than other portions of the container body.

  The delamination container of the present invention is the bottom of the completed form by reversing the bottom wall that has been formed to bulge outward. Thereby, at the time of inversion, the non-peeling part by which a part of said bottom wall was crimped | bonded to the inner wall of the trunk | drum lower end side can be formed comparatively easily. Since the non-peeled portion has a strong structure in which the inner and outer layers that are easily peeled are integrated and pressure-bonded by reversal, the spread of peeling can be suppressed at the non-peeled portion. Therefore, according to the present invention, it is possible to provide a delaminated peel container excellent in durability capable of preventing the spread of the peel with a relatively simple non-peel portion and maintaining the function of the laminated container.

It is shown about the lamination peeling container which concerns on this invention, and is the front view which showed the mode when it is a semi-finished product form in the state which the bottom wall which comprises a bottom part bulges after blow molding. It is the front view which showed the mode when the bulging part was reversed about the container shown in FIG. 1, and it was made the form of the finished product. It is shown about the lamination peeling container of the other form which concerns on this invention, and is the front view which showed the mode when it is a semi-finished product state in the state which the bottom wall which comprises a bottom part swells after blow molding. It is the front view which showed the mode when the bulging part was reversed about the container shown in FIG. 3, and it was made the form of the finished product.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a delamination container 1 according to the present invention, and is a front view showing a semi-finished product in a state where a bottom wall forming a bottom portion is bulged after being blow-molded. FIG. 2 is a front view showing a state where the bulging portion is inverted to form a finished product.
In FIG. 2, the lower right portion of the container is cut away to show a cross-sectional configuration, and the bulging portion is shown by a dotted line so that the correspondence with the semi-finished product form shown in FIG. 1 can be easily confirmed. Further, in FIG. 1, the bottom wall in the bulging state is indicated by 9A, and in FIG. 2, the bottom wall in the completed position is indicated by 9B.

  The delamination container 1 is a multi-layer synthetic resin container composed of an outer layer 2 having a shape-retaining property that forms the outer shape of the container, and an inner layer 3 that is detachably adhered to the inside thereof. For example, the delamination container 1 is bent and deformed by an outer layer 2 made of a synthetic resin material such as polyethylene or polypropylene, and a synthetic resin material made of nylon, ethylene vinyl alcohol copolymer, polyethylene terephthalate or the like that is less compatible with the outer layer 2. This is a blow molded container in which an inner layer 3 formed into a free bag shape is laminated.

  The body 4 of the container 1 has a cylindrical shape. The body 4 is erected on the upper end of the body 4, and a portion of the outer layer 2 before and after the mouth tube portion 5 in which a thread is engraved on the outer peripheral surface has an outside air. Is formed between the outer layer 2 and the inner layer 3, and a bottom portion 7 having a bottom wall 9 is connected to the lower end of the slightly enlarged diameter barrel portion 4.

The bottom portion 7 includes an annular bottom end wall 8 that serves as a ground contact portion of the container 1, a bottom wall 9 that is surrounded by the bottom end wall 8 and slightly depressed inside the container 1, and the bottom wall 9 And a bottom seal portion 12 which is located on the parting line and crosses the bottom wall 9.
As is clear from the above description, the annular bottom end wall 8 is located between the barrel 4 and the bottom wall 9 which are substantially upright cylindrical wall portions on the outside, and connects these components. It has become. In addition, the bottom wall 9 is in a state of being depressed inside the container 1 in the form of a finished product, but the bottom center portion CP on the center side is conversely convex downward. There is a bottom seal portion 12 in the bottom center portion CP. The bottom center portion CP will be described later.

  The bottom seal portion 12 of the bottom wall 9 is formed by a pinch-off portion of a blow molding die. The bottom seal portion 12 has a flat and protruding shape formed by crushing both the parison for the outer layer 2 and the parison for the inner layer 3. When a force is applied to the bottom seal portion 12 during a drop impact or when the container is used, peeling occurs and a bottom crack occurs. The laminated peeling container according to the present invention is provided with a structure that suppresses the spread and expansion of peeling when this peeling occurs. Furthermore, it demonstrates with reference to FIG.

The bottom wall 9B of the bottom 7 shown in FIG. 2 which is a form of the finished product is located between the body 4 and the bottom wall 9 with the bottom wall 9A in the state of bulging outward immediately after molding shown in FIG. It is formed by reversing around the annular bottom end wall 8.
Therefore, a region where a part of the bottom wall 9 is crimped to the inner wall 3 on the lower end side of the body portion 4 is formed by the inversion, and this becomes the non-peeling portion 20. The non-peeling portion 20 has a structure including an outer layer 2 and an inner layer 3 that are easily peeled off, but a two-layer inner layer 3 in which a pair of outer layers 2 positioned on the outer side is folded back by inversion is crimped. It becomes a strong structure to hold. Therefore, even if peeling occurs in the bottom seal portion 12, the non-peeling portion 20 functions as a region that regulates the peeling.
Further, as a result of the non-peeling portion 20 being formed by reversing the outer layer 2 and the inner layer 3 integrally (turning over from the bulging outside to the inside of the container) around the annular bottom end wall 8. The position is in the vicinity of the bottom end wall 8. Therefore, since the non-peeling part 20 acts so as to keep the generated peeling in the bottom part 7, it is possible to reliably prevent the peeling from spreading upward from the container. Since this lamination peeling container 1 can prevent expansion of peeling even if a bottom crack occurs, the function of the lamination container can be maintained and used continuously thereafter.

  In the lower right part of FIG. Referring to this, the outer layers 2-1 and 2-2 in which the inner wall 3-1 on the lower end side of the body portion 4 and the inner wall 3-2 on the bottom wall 9 side are located on the outer sides will be described in detail. As a result, a stacked structure is formed. The outer layer 2 is a resin such as polyethylene having a shape-retaining property, and has moderate elasticity, so after inversion, the outer layers 2-1 and 2-2 sandwich the inner layers 3-1 and 3-2 therebetween. Therefore, the non-peeling portion 20 can reliably stop the propagation of peeling. In addition, by appropriately adjusting the positions and opposing distances of the opposite outer layers 2-1 and 2-2 after inversion, the inner layer 3-1 and 3-2 are sandwiched and pressure-bonded, that is, the rigidity of the non-peeling portion 20 against peeling is increased. You can change it if necessary.

By the way, the bottom wall 9A formed in the bulged state has a dome shape that bulges downward from the container body, and is provided with an annular groove portion 10 in the middle position of the dome shape. The groove 10 acts so as not to invert the bottom center portion CP, which is a region closer to the center. That is, when the operation of reversing the bottom wall 9A as described above is performed, the region 11 between the annular groove portion 10 and the annular bottom end wall 8 is actually reversed, and the inner side of the annular groove portion 10 is reversed. The bottom center portion CP is designed so as to maintain a downwardly convex posture. For example, as shown in FIG. 2, TP-A on the groove 10 when in the bulging state becomes TP-B by inversion.
The bottom center portion CP includes at least a bottom seal portion 12. As described above, the bottom seal portion 12 has a structure that is easy to peel off. Therefore, if the inside of the dome-shaped bottom wall 9A shown in FIG. 1 is inverted as a whole, in the structure after the inversion is completed, the bottom seal portion 12 becomes the apex position where the inside rises. Such a structure is not preferable because a peeling force acts on the bottom seal portion 12. Therefore, as illustrated, an annular groove portion 10 is provided so that the bottom center portion CP maintains a downward posture, and an external force is not applied to the bottom seal portion 12.
Further, the annular bottom end wall 8 is preferably formed thinner than the other structural parts of the container body. Thereby, the reversing operation can be performed easily and reliably.
In addition, it is necessary to invert the bottom wall in order to change from the semi-finished product form with the bottom wall shown in FIG. 1 to the finished product form shown in FIG. However, this reversal operation is completed by a simple operation such as, for example, pushing the region 11 between the annular groove 10 and the annular bottom end wall 8 into the container. Therefore, the bottom wall inversion process can be easily automated, and can also be performed manually.

3 and 4 show a delamination container 1 according to another embodiment having different outer shapes. FIG. 3 shows another delamination container 1 according to the present invention, and is a front view showing a state of a semi-finished product in a state where a bottom wall forming a bottom portion is bulged after being blow-molded. is there. FIG. 4 is a front view showing a state of the container shown in FIG. 3 when the bulging portion is inverted to form a finished product.
3 and 4 show the delamination container similar to FIGS. Therefore, about the same site | part, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted and a different point is demonstrated about the lamination peeling container shown in FIG.

In the case of the delamination container 1, a constricted portion 30 having a reduced diameter is formed on the lower end side of the body portion 4, and the bottom side of the constricted portion 30 has a skirt-shaped inclined surface 31 that increases in diameter toward the outside. In addition, the lower end of the inclined surface 31 is continuous with the annular bottom end wall 8 described above. Therefore, when the bulging bottom wall 9A is inverted to become the bottom wall 9B, the inner wall 3-2 on the bottom wall 9B side is pressed against the inner wall 3-1 on the inner side of the inclined surface 31, and the non-peeling portion 20 Is formed.
In the case of the delamination container 1 shown in FIGS. 3 and 4, the lower side of the body part 4 is a flat inclined surface 31 having a certain size. Therefore, the inner wall 3-2 of the inverted bottom wall 9B is pressed against the inner wall 3-1 on the inner side of the inclined surface 31 to form a strong structure with a relatively wide crimping area. Thereby, the non-peeling portion 20 shown in FIGS. Therefore, the durability of the delamination container 1 shown in FIGS. 3 and 4 is further improved.

  As described above, according to the present invention, even if a bottom crack occurs, it is possible to suppress the spread of peeling at the non-peeling portion and to keep it at the bottom, so that the function of the stacked container is maintained and used continuously. It is possible to provide a delamination container with excellent durability. And since the non-peeling part can be formed only by the addition of a simple process of inverting the bottom wall swelled at the time of molding, the delamination container of the present invention is manufactured by making a simple change to the conventional production line. it can.

  According to the present invention, it is possible to provide a highly reliable delamination container that can maintain its original function even if a bottom crack occurs. For example, a container or a squeeze for containing contents that require hermeticity Can be widely used for specification containers.

DESCRIPTION OF SYMBOLS 1 Lamination peeling container 2 Outer layer 3 Inner layer 4 Trunk part 7 Bottom part 8 Annular bottom end wall 9 Bottom wall 10 Annular groove part 12 Bottom seal part 20 Non-peeling part 30 Constriction part

Claims (4)

A laminated peeling container in which a container body is blow-molded with an outer layer and an inner layer having low compatibility with the outer layer,
A bottom wall formed so that a bottom portion of the container body bulges outward is formed by inverting an annular bottom end wall positioned between the body portion of the container body and the bottom wall. And a non-peeling portion in which a part of the bottom wall is pressure-bonded to the inner wall on the lower end side of the body portion by the reversal. A constricted portion having a reduced diameter is formed on the lower end side of the body portion, and the lower side of the constricted portion is a skirt-shaped inclined surface that increases in diameter toward the outside, and the lower end of the inclined surface is Continuous with the annular bottom end wall;
The laminated peeling container according to claim 1, wherein the inverted bottom wall is pressed against the inner wall on the inner side of the inclined surface to form the non-peeling portion. The bottom wall formed in the bulging state is a dome shape that bulges downwardly from the container main body, and includes an annular groove in the middle position of the dome shape.
The delamination container according to claim 1 or 2, wherein the container is formed by inverting a region between the annular groove and the annular bottom end wall.   The laminated peeling container according to any one of claims 1 to 3, wherein the bottom end wall is formed thinner than the other part of the container body.