JP3871114B2 - Blow molding container - Google Patents

Description

[0001]
[Industrial application fields]
The present invention enables the inner layer forming a deformable inner bag to be peeled and laminated within the outer layer forming a fixed outer shell, and allows the content liquid to be poured out without changing the external shape. The present invention relates to a blow molded container made of a laminated release synthetic resin.
[0002]
[Prior art]
Known as a delaminated synthetic resin container, which is a blow-molded housing generally called a delamination bottle, which consists of an outer layer that forms a regular outer shell and an inner layer that forms a deformable inner bag. It has been.
[0003]
This blow-molded laminated exfoliated synthetic resin container is obtained by co-extrusion of an outer layer parison and an inner layer parison, which are almost incompatible, by extrusion molding into a laminated parison, and blow molding this laminated parison. The bottom seal part that is crushed and molded at the pinch-off part of this product is basically a laminated structure of an outer layer part and an inner layer part that have little compatibility, and there is a complaint that bottom cracks easily occur in the outer layer part. It was.
[0004]
As a conventional technology to eliminate this dissatisfaction, the bottom seal part, which is flattened by the pinch-off part of the blow mold, is molded into a ridge shape along the parting line by superposing and crimping a pair of rib pieces. However, there is a technique (see Japanese Patent Application Laid-Open No. 8-216238) in which a plurality of biting portions that bite from one of the pair of rib pieces to the other are provided on the protrusion.
[0005]
In this prior art, the bottom seal portion has a protrusion shape having a height and width, thereby increasing the pressure-bonding area between the outer layer and the inner layer in the bottom seal portion, and by providing a plurality of biting portions, the outer layer and the inner layer. In addition to further increasing the crimping area, the resistance against the shearing force parallel to the crimping surface is dramatically increased, thereby making it possible to obtain a bottom seal part with high mechanical strength that is less likely to cause bottom cracks. Yes.
[0006]
[Problems to be solved by the invention]
However, in the above-described prior art, bottom cracks may occur in the bottom seal part due to the effect of shrinkage of the bottom part after completion of the blow molding of the container. There is a problem that bottom cracks often occur when dropped in a state filled with or when an impact is applied.
[0007]
Therefore, this type of blow molded container needs to complete shrinkage in the mold, that is, cooling shrinkage, but the bottom seal portion has a large height width and thickness, so its volume becomes large, For this reason, there is a problem that it takes a long time for cooling, and the production efficiency of the container is extremely low.
[0008]
Therefore, the present invention was devised to solve the above-described problems in the prior art, and achieves a strong bond between the inner layer and the outer layer in the bottom seal portion without increasing the volume of the bottom seal portion. An object of the present invention is to provide a blow-molded container made of a laminated release synthetic resin, which is a technical problem, has high production efficiency, and is excellent in strength and economy.
[0009]
[Means for Solving the Problems]
Among the means of the present invention for solving the above technical problem, the means of the invention according to claim 1 is an outer layer made of a synthetic resin that forms a fixed outer shell by blow molding,
An inner layer made of a flexible synthetic resin that is peelably laminated with an outer layer to form an inner bag;
The outer layer and the inner layer are bonded and fixed over the entire height range, and are positioned almost symmetrically with respect to the central axis of the container and avoiding the air intake holes formed in the outer layer between the outer layer and the inner layer. Composed of two pairs of vertical strips, a total of four adhesive strips,
Each of the two adhesive bands is positioned opposite to each other with the parting line as a boundary, and each adhesive band in the bottom seal portion of the bottom portion formed by being flattened and molded by the pinch-off portion of the blow split mold The bottom width of the entire width of the bottom edge is opposed to the bottom edge of the opposite adhesive band in a one-to-one manner,
It is in.
[0010]
Since the container is blow-molded with a blow mold having a normal pinch-off part structure, that is, a blow molding split mold, the bottom seal part, which is a biting part formed at the bottom, is the same as a normal blow-molded product. It becomes a ridge shape with a low protrusion height.
[0011]
As described above, the volume of the bottom seal portion is sufficiently small, like the bottom seal portion of ordinary blow molded products, so that the cooling of the bottom seal portion can be achieved quickly and sufficiently when releasing the container. It will be possible.
[0012]
Two adhesive strips are positioned on opposite sides of the parting line, and the bottom width of each adhesive strip at the bottom seal part is one-to-one with the bottom edge of the opposite adhesive strip. At the two butted parts, the outer layer on both sides of the parting line and the inner layer sandwiched between the two outer layers are firmly bonded via the adhesive band within the range of the width of the lower edge of the adhesive band. It becomes a fixed state.
[0013]
In addition, there is no adhesive band in the region between the butted portions of the two adhesive bands, but since the outer layer and the inner layer are firmly bonded via the adhesive band on both sides, the outer layer and the inner layer are integrated. As a result, it is possible to obtain an adhesive fixing portion in which the outer layer and the inner layer are firmly bonded in a wide region in which the width of both adhesive bands and the width of the portion between the adhesive bands are combined.
[0014]
The three points of the adhesive fixing part and the right and left end parts of the bottom seal part as described above serve as knot points against deformation in the bottom seal part of the laminate composed of the outer layer and the inner layer, Even in a portion other than the adhesive fixing portion, deformation of the outer layer and the inner layer alone is suppressed, and as a result, even when a force is applied to the bottom seal portion, this force can be counteracted and the bottom seal portion is cracked. However, it is possible to make a wide range including the width of the part between the adhesive bands as an adhesive fixing part, so that the function as a knot is surely demonstrated, and the outer layer and the inner layer alone Since deformation is effectively suppressed, a sufficient crack prevention effect can be obtained.
[0015]
As described above, since the outer layer and the inner layer are integrated in a wide area that combines the width of both adhesive bands and the width between the adhesive bands, the width of the adhesive band itself can be set narrowly. It is possible to reduce the amount of costly adhesive material used.
[0016]
The adhesive band positioned over the entire height range functions to regulate the inner layer's wrinkle deformation, and the contents can be smoothly poured out.
[0017]
The invention described in claim 2 is obtained by adding the configuration of the invention described in claim 1 to two outer layer portions in the vicinity of the parting line so as to be substantially axisymmetric with respect to the central axis of the container.
[0018]
According to the configuration of the second aspect, since the outside air does not enter in the region between the two adhesive bands located in the same direction with the parting line as a boundary, the separation between the outer layer and the inner layer does not proceed. It becomes possible to hold the integration of the outer layer and the inner layer in the region between the butted portions of the two adhesive bands of the seal portion more reliably.
[0019]
Moreover, since the area | region which added the width | variety between two adhesive bands and the width | variety between adhesive bands fulfill | performs the function which regulates the wrinkle deformation of an inner layer, it is possible to narrow the width | variety itself of an adhesive band.
[0020]
The invention according to claim 3 is the configuration of the invention according to claim 2, wherein the inner layer portion that can be deformed by deflating the width between two adhesive bands located in the same direction with the parting line as a boundary, When the contents are used up, the flat cross section of the body of the container is set so as to be closed.
[0021]
According to the configuration of the third aspect, it is possible to prevent complete collapse of the trunk flat section when the contents still remain, and the trunk flat section is completely collapsed when the contents are almost used up. Therefore, it becomes possible to use up almost all of the contents while securing the flow passage of the contents and maintaining good pouring properties.
[0022]
The invention according to claim 4 is obtained by adding the intake hole to the outer layer portion of the mouth tube portion in addition to the configuration of the invention according to claim 1, 2 or 3.
[0023]
In the invention according to claim 4, since the intake hole is opened in the mouth tube portion covered with the cap, the intake hole does not deteriorate the appearance of the container, and the intake hole is cut and formed by post-processing. In doing so, since the thickness of the inner layer portion in the mouth tube portion is large, the intake hole can be easily cut and formed without making a hole in the inner layer portion.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIGS. 1 to 7 show an embodiment of a container 1 according to the present invention. This container 1 is an outer shell made of a synthetic resin material such as polyethylene and polypropylene and having a necessary self-shape retaining ability. A synthetic resin material having low compatibility with the outer layer 2 such as nylon, ethylene vinyl alcohol copolymer, polyethylene terephthalate, etc., and an inner layer 3 formed into a bag shape that can be flexibly deformed. Two pairs of vertical strips formed in an adhesive resin exhibiting sufficient adhesion to the outer layer 2 and the inner layer 3 and provided over the entire height range of the container 1, a total of four adhesive strips 4 This is a laminated blow molded container.
[0025]
The barrel portion 6 of the container 1 has a cylindrical shape, and is provided in an upright position at the upper end of the barrel portion 6 and is an outer layer at the position of the left and right parting lines 5 of the mouth tube portion 7 in which a thread is engraved on the outer peripheral surface. The two portions are provided with intake holes 9 for introducing outside air between the outer layer 2 and the inner layer 3.
[0026]
Four adhesive bands 4 (4a1, 4a2, 4b1, 4b2) are located across a position displaced by a substantially central angle of 90 ° with respect to the intake hole 9, and 4a1 and 4b2 and 4a2 and 4b1 are shafts. Two adhesive bands 4 (4a1 and 4b1 and 4a2 and 4b2) on the same side with the parting line 5 as a boundary in the body 6 and a portion sandwiched between the two adhesive bands 4 The width of the combined region (hereinafter referred to as the fixed band 13) is set to be (1/4) (L-2D). (L: circumference of trunk flat section, D: diameter of trunk flat section)
[0027]
A bottom portion 8 having a bottom wall recessed in a spherical arc shape is connected to the lower end of the body portion 6, and the bottom portion 8 (see FIGS. 3 and 4) is formed around the bottom wall of the leg portion of the container 1. In the center of the bottom surface of the bottom wall, a bottom seal portion 10 is formed which is located on the parting line 5 and substantially crosses the bottom wall and is crushed and cut by a pinch-off portion of a blow mold. It has a configuration.
[0028]
Blow molding of the container 1 is performed by two pairs of symmetrically arranged outer cylinders that are the outer layer 2, an inner cylinder that is the inner layer 3 located inside the outer cylinder, and the outer cylinder and the inner cylinder. The narrow strip-shaped adhesive strip 4 is co-extruded to extrude the parison, and this parison is blow molded into the container 1 with a blow molding split mold.
[0029]
When blow-molding the container 1, the parison is attached to the blow-molding mold so that two pairs, a total of four adhesive bands 4, are positioned in the vicinity of the mold-clamping direction of the blow-molding mold. The posture is set, and the adhesive band 4 reaches the bottom seal portion 10 located on the parting line 5 of the bottom portion 8 as shown in FIG.
[0030]
Further, 4a1 and 4a2 and 4b1 and 4b2 of the adhesive band 4 located on the opposite side with the parting line 5 as a boundary are provided at one bottom edge of the bottom seal portion 10 as shown in FIGS. The full width is located in a one-to-one butting manner at the opposite lower end edge. (Hereinafter, the portion where the two adhesive bodies are located in a butting manner is referred to as a butting portion 12.)
[0031]
Therefore, as shown in FIGS. 5 and 6, the outer layer 2 on both sides of the parting line 5 in the portion where the butt portion 12 is located in the bottom seal portion 10 which is a biting portion, and the inner layer 3 sandwiched between the outer layers 2. Is firmly bonded and fixed by the adhesive band 4, and the adhesive band portion 14 between both butted portions 12 is also fixed at both sides by the butted portions 12, and the inner layer or the outer layer alone is deformed. As a result, the strong bonding between the outer layer 2 and the inner layer 3 is achieved in a wide region in which the width of both the adhesive bands 4 and the width of the portion 14 between the adhesive bands are combined.
[0032]
Further, in this embodiment, since the intake hole 9 is located on the parting line 5 of the mouth tube portion 7, the deflation of the inner layer 3 due to a decrease in internal pressure, a decrease in the contents 15, etc. While the pair of fixing bands 13 formed at positions displaced by a substantially central angle of 90 ° with respect to the function of regulating deformation, between the adhesive bands 4a1 and 4a2 and between the adhesive bands 4b1 and 4b2 It progresses in the two inner-layer deformation | transformation parts 11 located in FIG.
[0033]
When the progress of the deformation of the inner layer deformed portion 11 is seen in the plane section of the body portion 6 as the contents 15 are poured out, the central portion of the left and right inner layer deformed portions 11 is first deformed into a flat shape. Progresses and contacts at approximately the center, and further, the contact portion extends to press the contents 15 in the circumferential direction and the portion where the fixing band 13 is formed. Progresses. (See Figure 7)
[0034]
When the content 15 further pours and the wrinkle deformation progresses, the content 15 almost disappears, and the plane cross section is almost completely crushed. Here, the length of the inner layer deformed portion 11 is approximated. Is set equal to the sum of the diameter D of the cross section of the body 6 and the width of the fixed band 13, that is, the width of the fixed band 13 is set equal to (1/4) (L-2D). The contents 15 can be almost used up while securing the flow passage.
[0035]
In the above-described embodiment, the container 1 has been described as a two-layer structure of the outer layer 2 and the inner layer 3. However, the inner layer 3 is not limited to a single-layer structure, and, for example, peelability from the outer layer 2 on the outer side. It goes without saying that a layer made of a synthetic resin having the above and a layer made of a synthetic resin excellent in liquid content resistance may be laminated on the inside.
[0036]
【The invention's effect】
Since the present invention has the above-described configuration, the following effects can be obtained.
In the first aspect of the invention, since the cooling of the bottom seal portion of the container can be quickly and sufficiently achieved, the production cycle of the container can be increased to the same level as that of a normal blow molded product. .
[0037]
Further, it is not necessary to use a special mold in consideration of mold cooling efficiency, and a normal mold can be used, so that a significant reduction in equipment cost can be achieved.
[0038]
In addition, the outer layer and the inner layer of the bottom seal portion can be firmly bonded to each other in a wide area including the width of the two adhesive bands and the width between the adhesive bands. A reduction in the mechanical strength of the bottom seal portion due to molding with the synthetic resin material can be surely and sufficiently prevented.
[0039]
Furthermore, although a total of four adhesive bands are arranged, it is a configuration that achieves strong bonding including the width between the adhesive bands as described above, and the width of the adhesive band itself can be set narrow, The amount of the adhesive material having a high material cost can be reduced.
[0040]
In the invention of claim 2, since there is no separation of the inner layer from the outer layer in the fixed band portion, the outer layer and the inner layer in the region between the butted portions of the two adhesive bands of the bottom seal portion are integrated. It becomes possible to hold it more reliably.
[0041]
In the invention according to the third aspect, it is possible to use up almost the entire amount of the contents while securing a flow passage for the contents and maintaining a good pouring property.
[0042]
In the invention according to claim 4, the air intake hole can be opened without adversely affecting the appearance of the container, and the air intake hole can be opened and formed safely and easily by post-processing. it can.
[Brief description of the drawings]
FIG. 1 is an overall perspective view with a part broken away, showing an embodiment of the present invention.
FIG. 2 is a plan sectional view of the embodiment shown in FIG.
3 is a bottom view of the embodiment shown in FIG. 1. FIG.
4 is an enlarged vertical sectional view of the bottom of the embodiment shown in FIG.
FIG. 5 is an enlarged view of a bottom seal part in FIG. 4;
6 is an enlarged view of a bottom seal portion in FIG. 3. FIG.
7 is an explanatory view showing the transition of deformation of the inner layer in the plan sectional view shown in FIG. 2. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1; Container 2: Outer layer 3; Inner layer 4; Adhesive band 4a1; Adhesive band 4a2; Adhesive band 4b1; Adhesive band 4b2; Adhesive band 5; Parting line 6; Body part 7; Mouth part 8; 10; bottom seal part 11; inner layer deformation part 12; butt part 13; fixing band 14; adhesive band part 15;

Claims (4)

An outer layer (2) made of a synthetic resin that forms a fixed outer shell by blow molding, and an inner layer (3) made of a flexible synthetic resin that is peelably laminated with the outer layer (2) to form an inner bag The outer layer (2) and the inner layer (3) are bonded and fixed over the entire height range, the outer layer (2) formed substantially symmetrically with respect to the central axis of the container (1) ( 2) and the inner layer (3) are composed of two pairs of vertical narrow strips, which are located avoiding the air intake holes (9) that allow the outside air to enter, and a total of four adhesive strips (4). The bottom seal of the bottom part (8) formed by crushing flatly by the pinch-off part of the blow mold, and placing the two parts 4) on opposite sides of the parting line (5). A blow-molded container in which the entire width of the lower end edge of each adhesive band (4) in the section (10) is opposed to the lower end edge of the opposite adhesive band (4) in a one-to-one manner. The blow molded container according to claim 1, wherein the intake holes (9) are provided in two outer layer (2) portions in the vicinity of the parting line (5) so as to be substantially axisymmetric with respect to the central axis of the container (1). In the body part (6), the width of the two adhesive bands (4) located in the same direction with the parting line (5) as the boundary, the part of the inner layer (3) that can be deflated and deformed is the contents ( The blow-molded container according to claim 2, wherein the blow-molded container is set so that the flat section of the body (6) of the container (1) can be just plugged when 15) is used up. The blow molded container according to claim 1, 2, or 3, wherein the intake hole (9) is provided in the outer layer (2) portion of the mouth tube portion (7).

Images