JP6806986B2 - Molded products and their manufacturing methods and equipment - Google Patents

Description

The present invention relates to a molded product, a method for producing the same, and a manufacturing apparatus thereof.

Conventionally, various mold assemblies and molding methods are known for molding a molded product (for example, Patent Document 1).

Patent Document 1 is composed of a first mold portion and a second mold portion, and at the time of mold clamping, a cavity for molding a molded product based on a thermoplastic resin is formed inside, and molding of the molded product is performed. At the time, a mold having a structure capable of making the volume of the cavity variable, a die arranged in the first and / or second mold portion and forming a part of the cavity, and a mold in which the nest is arranged. A mold for injection compression molding, which is attached to a portion, forms a part of a cavity, and includes a holding plate for holding the end of the nest, and a protruding pin slidably arranged in the first mold portion. The assembly is disclosed. The molded product is configured so that both ends of the molded product are projected by two protruding pins to be demolded, but both ends of the molded product and thus the parting surface of the corresponding cavity are substantially parallel to the demolding direction. It is a straight line (see FIG. 3 and others in Patent Document 1).

However, in the configuration of Patent Document 1, when the periphery of both ends of the molded product protrudes from the center, that is, the parting surface of the corresponding cavity is in the demolding direction from the front surface side of the mold to the bottom surface side. In the case of deep digging in the intersecting direction, if both ends of the molded product are to be demolded by two protruding pins, both ends of the molded product will collide with the parting surface and be damaged. There was a problem.

Japanese Unexamined Patent Publication No. 9-207176

The present invention has been made based on such circumstances, and an object of the present invention is a molded product whose bottom surface is not damaged even if the molded product has a bottom surface whose periphery protrudes from the center, and a molded product thereof. The purpose is to provide a manufacturing method and a manufacturing apparatus.

The present invention is grasped by the following configuration.
(1) The first aspect of the present invention is a pair of laminated stripping containers as an intermediate molded product, which are positioned so that the first laminated stripping container and the first laminated stripping container face each other. The pair of laminated stripping containers are provided with a second laminated stripping container and a central burr portion that connects the mouth of the first laminated stripping container and the mouth of the second laminated stripping container. When the mold formed from the inner layer that is not adhered to the outer layer and composed of the first mold plate and the second mold plate facing the first mold plate is opened, the first mold plate is opened. The central burr portion of the pair of laminated peeling containers left in the first mold plate is formed so as to be projected and bent toward the second mold plate by a protruding pin provided on the back plate of the first mold plate. It is characterized by being.

(2) In the configuration of the above (1), the central burr portion comprises a thick portion near the center, a mouth portion of the first laminated peeling container, and a thin portion near the mouth of the second laminated peeling container. Have.

(3) In the configuration of (2) above, the thick portion and the thin portion have a wall thickness ratio in the range of 2: 1 to 4: 3.

(4) In the configuration of (2) or (3) above, the thick portion is shaped so as to be easily bent.

(5) In any one of the above (1) to (4), the outer layer is made of low density polyethylene (LDPE) or linear low density polyethylene (LLDPE).

(6) In any one of the above (1) to (4), the outer layer has a flexural modulus in the range of 160 to 340 MPa.

(7) A second aspect of the present invention is a method for manufacturing a pair of laminated stripping containers as an intermediate molded product connected by a central burr portion, wherein the first mold plate and the first mold plate face each other. A step of mold-fastening a mold composed of a second mold plate, a step of opening the mold, and the central burr portion of the pair of laminated peeling containers left on the first mold plate. It is characterized by comprising a step of projecting and bending toward the side of the second mold plate by a protruding pin provided on the back plate of the first mold plate.

(8) In the configuration of (7) above, a take-out pin is further attached to an end burr portion attached to a pinch portion provided at the bottom of the first laminated peeling container or the second laminated peeling container of the pair of laminated peeling containers. It is provided with a step of inserting and taking out the pair of laminated peeling containers from the first mold plate in a state where the central burr portion of the pair of laminated peeling containers is extruded by the protruding pins.

(9) A third aspect of the present invention is an apparatus for manufacturing a pair of laminated stripping containers as an intermediate molded product connected by a central burr portion, in which the first mold plate and the first mold plate face each other. A mold composed of a second mold plate and a protruding pin provided on the back plate of the first mold plate are provided, and when the mold is opened, the protruding pin is the first mold. The central burr portion of the pair of laminated stripping containers left on the plate is projected toward the side of the second mold and bent.

(10) In the configuration of (9) above, the pair is further inserted into an end burr portion attached to a pinch portion provided at the bottom of the first laminated peeling container or the second laminated peeling container. The pair of laminated strips is provided with a take-out pin for taking out the pair of laminated stripped containers from the first mold plate, and the take-out pin is in a state where the central burr portion of the pair of laminated stripped containers is extruded by the protruding pin. Take out the peeling container.

According to the present invention, it is possible to provide a molded product whose bottom surface is not damaged even if the molded product has a bottom surface such that its periphery protrudes from the center, and a manufacturing method and manufacturing apparatus thereof.

It is a figure which shows the laminated peeling container as a final molded article which concerns on embodiment of this invention, (a) is a front view, (b) is a rear view, (c) is a side view, (d) is a plan view. (E) is a bottom view. Similarly, it is a side sectional view of the laminated peeling container. Similarly, it is an enlarged view of the bottom surface of the laminated peeling container. It is a figure which shows a pair of laminated peeling containers as an intermediate molded article which concerns on embodiment of this invention in the process, (a) is a figure before inserting a multi-layered parison into a split die, (b) is a figure. The figure which closed the split mold, (c) is the figure which opened the split mold. It is a figure explaining the mode of taking out a pair of conventional laminated stripping containers from a split die. It is a figure explaining the mode to take out a pair of laminated peeling containers which concerns on embodiment of this invention. Similarly, it is a figure explaining that a pair of laminated peeling containers is bent in a dogleg shape. Similarly, it is sectional drawing of a pair of laminated peeling containers. It is a figure which shows the outline of the structure of the split mold which concerns on embodiment of this invention. Similarly, it is a figure which shows the outline of the structure of the protrusion pin provided in the 1st mold among the split molds. Similarly, it is a figure which shows the outline of the structure of the 2nd mold among the split molds. Similarly, it is a figure which shows the outline of the structure of the blow nozzle provided in the 2nd mold among the split molds.

Hereinafter, embodiments for carrying out the present invention (hereinafter, embodiments) will be described in detail with reference to the accompanying drawings.

In the present embodiment, the finally molded final molded product is described as a laminated peeling container 1, and a pair of intermediate molded products intermediately molded in a state of being connected by a split mold 80 having two pieces on one side. It will be described as a laminated peeling container 10, 10'. Matters common to both are given the same terms and symbols.

(Laminate peeling container 1)
First, the laminated peeling container 1 as a final molded product will be described with reference to FIGS. 1 to 3. As shown in FIG. 1, the laminated peeling container 1 includes a container body 2 and a valve member 9. The contents of the laminated peeling container 1 are, for example, eye drops, fluid foods, and the like.

((Container body 2))
The container body 2 is composed of an accommodating portion 3 for accommodating the contents and a mouth portion 4 for discharging the contents. The accommodating portion 3 includes a shoulder portion 5 extending downward from the mouth portion 4 and a body portion 6 extending vertically downward from the shoulder portion 5. In applying this embodiment, the container body 2 is not limited to the shape shown here, and can be set in consideration of the contents, the size of the container, and the like.

A bottomed hole 61 for arranging the valve member 9 and a recess 62 for facilitating the user to put a finger when pushing out the contents are provided on the front surface of the body portion 6. A parting line 21 is formed on the side surface of the container body 2 when molding using a mold, and a pinch portion 22 is formed on the bottom surface 31 of the container body 2 at a position extending from the parting line 21. It is provided.

Here, as will be described in detail later, in the laminated peeling container 1 according to the present embodiment, the inner layer 1b (inner bag) filled with the contents becomes the outer layer 1a (outer shell) as the contents are consumed and reduced. ) Is a "Hakuri Bottle (registered trademark)", and the inner layer 1b and the outer layer 1a are not adhered to each other. Further, in the pinch portion 22, the crimping portion 22b located below the base portion 22a closest to the bottom surface 31 of the container body 2 is crimped and sealed, but the tip portion 22c is not crimped. Since the pinch portion 22 is easily cracked when strongly pressed, the pinch portion 22 can be set longer by setting the bottom surface 31 of the container body 2 toward the center as a raised bottom.

FIG. 2 shows the cross-sectional structure of the container body 2. As shown in FIG. 2, the container body 2 has a multilayer structure of an outer layer 1a and an inner layer 1b in the accommodating portion 3 and the mouth portion 4, and the outer layer 1a is the outer shell of the laminated peeling container 1 and the inner layer 1b is the content. It constitutes an inner bag for filling things.

As described above, in the laminated peeling container 1, the inner layer 1b (inner bag) filled with the contents is peeled from the outer layer 1a (outer shell) as the contents are consumed or reduced. Trademark) ". The inner layer 1b and the outer layer 1a are not adhered to each other, and air is introduced between the outer layer 1a and the inner layer 1b by the action of the valve member 9, so that the inner layer 1b becomes the outer layer 1a as the contents are consumed and reduced. It will be peeled off from.

Here, the inner layer 1b is provided with an oxygen barrier property, and the laminated peeling container 1 reduces the contact between the contents and the air by such a double peeling structure, and enhances the holding power of the freshness of the contents. There is. That is, in a container having a single-layer structure, air invades the space formed in the container after the contents are discharged and comes into direct contact with the contents, and air also invades from the outer shell even during storage. Oxidation of the contents progresses quickly, and deterioration is accelerated. On the other hand, in the laminated peeling container 1, as the contents are consumed and reduced, air is introduced between the inner layer 1b and the outer layer 1a by the valve member 9, so that the mouth portion 4 after the contents are discharged. In addition to preventing air from entering the inner layer 1b, the air that has entered from the outer layer 1a is blocked by the inner layer 1b even during storage, so oxidation of the contents is significantly suppressed and deterioration is suppressed. It works.

Further, since the inner layer 1b is flexible, the contents can be squeezed out by a desired amount, while the outer layer 1a has a predetermined hardness and therefore returns to the original shape even if the contents are reduced. The laminated peeling container 1 can be placed upright at any time regardless of the remaining amount of the contents.

A locking portion 4d is provided on the mouth portion 4, and a cap having a female screw, a pump, or the like (both not shown) is attached to the locking portion 4d. Further, the mouth portion 4 is provided with an inner layer support portion 4c that suppresses the displacement of the inner layer 1b at a position close to the shoulder portion 5 of the accommodating portion 3. The inner layer support portion 4c is formed by providing a constriction in the mouth portion 4. Since the inner layer support portion 4c suppresses the inner layer 1b from slipping off, it is possible to prevent the inner layer 1b constituting the inner bag from falling into the outer layer 1a constituting the outer shell.

As described above, the accommodating portion 3 includes a shoulder portion 5 extending from the mouth portion 4 in an expansive manner and a body portion 6 extending downward from the shoulder portion 5. A bent portion 5a is formed at the boundary between the mouth portion 4 and the shoulder portion 5. When there is no bent portion 5a, the peeling between the inner layer 1b and the outer layer 1a spreads from the body portion 6 to the mouth portion 4 via the shoulder portion 5, and the inner layer 1b and the outer layer 1a are also peeled off at the mouth portion 4. There is a possibility that it will end up. If this happens, the inner bag composed of the inner layer 1b will fall off into the outer shell composed of the outer layer 1a at the mouth portion 4, and the contents will be discharged from the mouth portion 4 according to the application. It will be difficult.

In the present embodiment, in order to prevent such a situation, by providing the bent portion 5a, when the peeling between the inner layer 1b and the outer layer 1a spreads from the body portion 6 to the bent portion 5a, the inner layer 1b becomes the bent portion 5a. By hanging downward, the force for peeling the inner layer 1b from the outer layer 1a is not transmitted to the upper portion of the bent portion 5a, and as a result, between the inner layer 1b and the outer layer 1a in the portion above the bent portion 5a. Peeling is suppressed.

As described above, the bottom surface 31 of the accommodating portion 3 has a raised bottom, and is composed of a central concave region 31a having a raised bottom and a peripheral region 31b provided around the central concave region 31a. The pinch portion 22 described above protrudes from the central concave region 31a of the bottom surface 31, and the pinch portion 22 has a base portion 22a, a crimping portion 22b, and a tip portion 22c in this order from the bottom surface 31 side, as shown in FIG. Includes.

((Valve member 9))
As shown in FIG. 2, the accommodating portion 3 of the container body 2 is provided with a valve member 9 in a bottomed hole 61 provided in a body portion 6 directly below the shoulder portion 5. The valve member 9 is fitted into an air introduction hole 61a penetrating the outer layer 1a of the bottomed hole 61. An intermediate space 1c in which air is initially introduced is formed between the bottomed hole 61 and the outer layer 1a and the inner layer 1b corresponding to the periphery thereof, and the valve member 9 is located between the intermediate space 1c and the outer space S. Adjust the inflow and outflow of air. That is, when the user pushes the recess 62 of the container body 2 with a finger, the pressure inside the container body 2 rises and the valve member 9 closes, and when the finger is released from the container body 2 after discharging the contents, the valve member 9 opens. Air is introduced by opening. As a result, the intermediate space 1c gradually expands, and the inner layer 1b, which is the inner bag, is separated from the outer layer 1a, which is the outer shell.

As the valve member 9, various forms may be adopted, but in FIG. 2, the shaft portion 9a inserted into the air introduction hole 61a and the shaft portion 9a provided on the intermediate space 1c side of the shaft portion 9a are provided. An example is shown in which a lid portion 9c having a larger cross-sectional area and a locking portion 9b provided on the outer space S side of the shaft portion 9a to prevent the valve member 9 from entering the intermediate space 1c are provided.

The lid portion 9c has a tapered shape so as to expand in a direction away from the shaft portion 9a, and when the outer layer 1a is compressed, the lid portion 9c moves to the shaft portion 9a side and closes the air introduction hole 61a. The locking portion 9b is configured in a bridge shape and is configured to bend toward the air introduction hole 61a, and as shown by an arrow F1, a restoring force is generated on the outside of the container body 2, that is, in the direction away from the container body 2. As a result, an urging force in the same direction acts on the lid portion 9c, and the lid portion 9c is pressed against the air introduction hole 61a from the side of the intermediate space 1c.

In this state, the lid portion 9c is only lightly pressed against the air introduction hole 61a, but when the outer layer 1a is compressed from the outside, the pressure in the intermediate space 1c becomes higher than the external pressure, and the lid due to this pressure difference. The portion 9c is pressed more strongly against the air introduction hole 61a, and the lid portion 9c closes the air introduction hole 61a more firmly.

When the outer layer 1a is further compressed in this state, the pressure in the intermediate space 1c increases, and as a result, the inner layer 1b is compressed and the contents in the inner layer 1b are discharged. Then, when the compressive force on the outer layer 1a is released, the outer layer 1a is restored by its own elasticity. As the pressure inside the intermediate space 1c is reduced as the outer layer 1a is restored, a force F2 in the inner direction of the container body 2 is applied to the lid portion 9c. As a result, the lid portion 9c moves inside the container body 2 due to the large deflection of the bridge-shaped locking portion 9b, a gap is created in the air introduction hole 61a, and air is introduced into the intermediate space 1c.

The valve member 9 is attached to the container body 2 by inserting the valve member 9 into the intermediate space 1c while the lid portion 9c expands the air introduction hole 61a. Therefore, it is preferable that the tip of the lid portion 9c has a tapered shape. Since such a valve member 9 can be mounted by simply pushing the lid portion 9c into the intermediate space 1c from the outside of the container body 2, it can be easily arranged.

(A pair of laminated stripping containers 10, 10')
Next, the pair of laminated stripping containers 10, 10'as intermediate molded products will be described with reference to FIGS. 4 to 8. The pair of laminated stripping containers 10, 10'are formed by taking two pieces on one side with a split mold 80 (described later) in order to obtain the laminated stripping container 1 described above. As shown in FIG. 4C, the pair of laminated peeling containers 10 and 10'are located so that the first laminated peeling container 10 and the first laminated peeling container 10 and their mouths 4 face each other. It includes a laminated peeling container 10'and a central burr portion 7 that connects the mouth 4 of the first laminated peeling container 10 and the mouth 4 of the second laminated peeling container 10'. The first end burr portion 71 and the second end burr portion 71'are attached to the bottom surface 31 of the first laminated peeling container 10 and the second laminated peeling container 10', respectively.

Molding of the pair of laminated stripping containers 10, 10'is performed as follows as a manufacturing method. First, as shown in FIG. 4A, the laminated parison P in the molten state is extruded from the die head DH, and the laminated parison P in the molten state is blow-molded into various shapes of the container body 2. It is set in the split mold 80 to be held, and the split mold 80 is closed. Next, as shown in FIG. 4B, air is blown into the cavity 81 of the split mold 80 from one direction of the central burr portion 7 in a state where the mold is tightened (for the blow nozzle 82 that blows air). , See FIGS. 9, 11 and 12). Then, as shown in FIG. 4C, the split mold 80 is opened and the pair of laminated stripping containers 10, 10'are taken out.

Here, the case where the split mold 80 has the following configuration will be described. The split mold 80 is composed of a first mold plate 80a and a second mold plate 80b facing the first mold plate 80a. The first mold plate 80a is a fixed mold plate and the second mold plate 80b is movable. Use as a template. When the split mold 80 opens, that is, when the second mold plate 80b moves in the direction of retracting from the first mold plate 80a, the pair of laminated peeling containers 10, 10'are left in the first mold plate 80a.

When taking out the pair of laminated stripping containers 10, 10', their bottom surfaces 31 are composed of a central concave region 31a having a raised bottom and a peripheral region 31b provided around the central concave region 31a as described above. Therefore, as shown in FIG. 5, when the pin is projected in the vicinity Y of the bottom surface 31 of the pair of laminated peeling containers 10 and 10'as in the conventional case, the bottom surface 31 surrounded by the range X is the cavity 81. The bottom surface 31 may be damaged if it is forcibly taken out because it collides with the surface of the container to reduce the take-out property. Therefore, the bottom surface 31 and / or the pinch portion 22 is taken out in the following manner so that it can be taken out from the first template 80a smoothly and without being damaged. In the pair of laminated peeling containers 10 and 10'as in the conventional case, the central burr portion 7 "has substantially the same diameter as the mouth portion 4.

That is, as shown in FIG. 6, on the side opposite to the nozzle hole 41 opened by the blow nozzle 82 inserted from the second template 80b side, the back plate 80aa side of the first template 80a and the central burr. The protruding pin 83 provided at the position Y corresponding to the portion 7 is abutted against the central burr portion 7. By projecting the pin 83 against the contact portion 7d of the central burr portion 7, the central burr portion 7 is projected from the first template 80a in the pair of laminated peeling containers 10, 10', and the central burr portion 7 is centered. It bends in a "<" shape.

Then, a gap is formed between the slope of the central concave region 31a on the bottom surface 31 surrounded by the range X of the pair of laminated peeling containers 10, 10'and the corresponding surface of the cavity 81 of the first template 80a, and the pair The laminated peeling containers 10, 10'can be taken out from the first template 80a so that the bottom surface 31 and / or the pinch portion 22 is smoothly and not damaged. After being taken out, the first end burr portion 71 and the second end burr portion 71'are removed. At this time, it is preferable that the protruding pin 83 is maintained in a protruding state while the pair of laminated stripping containers 10, 10'are taken out from the first template 80a.

As shown in FIG. 7, the pair of laminated peeling containers 10, 10'protruded by the projecting pin 83 is bent in a dogleg shape as a whole, but the bent portion is only the central burr portion 7. The portion of the laminated peeling container 1 which is the final molded product does not bend, and the quality of the product is not affected.

The pair of laminated stripping containers 10, 10'bent in a dogleg shape in this way are taken out from the split die 80 by inserting an take-out pin (not shown) into the first end burr portion 71. The pair of laminated peeling containers 10 and 10'taken out from the split mold 80 have holes only in the outer layer 1a at the central burr portion 7 above the mouth portion 4, and the outer layer 1a and the inner layer 1b are formed. By blowing air between them using a blower, the inner layer 1b is preliminarily peeled from the outer layer 1a in the bottomed hole 61 of the accommodating portion 3 to which the valve member 9 is attached. Then, an air introduction hole 61a is formed in the outer layer 1a by using a drilling device. Then, the valve member 9 is inserted into the air introduction hole 61a. The air introduction hole 61a is preferably a round hole, but may have a different shape. After that, the central burr portion 7 is removed.

(Central burr part 7)
Here, the configuration of the central burr portion 7 will be described in more detail with reference to FIG. As shown in the figure, the central burr portion 7 includes a pair of connecting portions 7a, 7a'extending from the pair of mouth portions 4 of the pair of laminated peeling containers 10 and 10'with the same diameter as the pair of mouth portions 4. It is composed of a central portion 7b closer to the center that connects them with a diameter smaller than that of the pair of connecting portions 7a and 7a'. As a result, the central burr portion 7 is easily bent between the central portion 7b and the pair of connecting portions 7a, 7a'. The protruding pin 83 projects the contact portion 7d of the central portion 7b.

Further, as a mode in which it is easy to bend, the wall thickness of the central portion 7b to which the protruding pin 83 hits is set to the boundary between the pair of connecting portions 7a, 7a'and the central portion 7b, and the mouth portion 4 of the first laminated peeling container 10 and It is preferable that the thickness of the boundary portion 7c, which is closer to the mouth portion 4 of the second laminated stripping container 10', is larger than the wall thickness. For example, the central portion 7b can be 1.2 mm to 1.4 mm, and the boundary portion 7c can have a wall thickness of 0.7 mm to 0.9 mm. When this is expressed by the wall thickness ratio between the central portion 7b and the boundary portion 7c, it is in the range of 2: 1 to 4: 3. In the present embodiment, the portion when the wall thickness of the central portion 7b is increased is also referred to as a thick portion, and the portion when the wall thickness of the boundary portion 7c is reduced is also referred to as a thin portion.

If the difference in the wall thickness ratio is larger than the above range, there is a possibility that the boundary portion 7c will break when the central portion 7b is projected by the protruding pin 83. Further, since the resin cools at a different speed between the central portion 7b and the boundary portion 7c, warpage occurs. In that case, the outer layer 1a and the inner layer 1b are expected in the pair of laminated stripping containers 10 and 10'. It may cause peeling and affect the laminated peeling container 1 which is the final molded product. On the other hand, if the difference in wall thickness ratio is too small than the above range, the boundary portion 7c becomes difficult to bend, and depending on the depth of the central concave region 31a of the bottom surface 31, the pair of laminated stripping containers 10, 10' May be difficult to remove.

Furthermore, in addition to or instead of setting the wall thickness ratio between the central portion 7b and the boundary portion 7c, a shape that facilitates bending of the central burr portion 7, for example, a bellows shape or a constricted shape in the central portion 7b. Etc. may be applied.

Furthermore, in addition to or in place of setting the wall thickness ratio between the central portion 7b and the boundary portion 7c and imparting the easily bent portion 40d to the central portion 7b, within a range that satisfies the performance required for the laminated peeling container 1. The outer layer 1a and the inner layer 1b may be formed of a combination of materials such that the central burr portion 7 is easily bent. The laminated structure will be described again in the section.

The split mold 80 for forming the pair of laminated stripping containers 10, 10'has a configuration as shown in FIGS. 9 to 12. That is, as shown in FIG. 9, the split mold 80 includes a first mold plate 80a as a fixed side and a second mold plate 80b on the movable side, and a pair of laminated peeling containers 10 and are provided on the inner surface thereof. A cavity 81 for forming the 10'is dug. As shown in FIG. 10, the first mold plate 80a of the split mold 80 is provided with a protruding pin 83. FIG. 11 shows the configuration of the second mold plate 80b of the split mold 80, and as shown in FIG. 12, the second mold plate 80b is provided with a blow nozzle 82.

(Laminated structure)
The laminated structure of the laminated stripping container 1 and the pair of laminated stripping containers 10, 10'will be described. The container body 2 is composed of an outer layer 1a and an inner layer 1b, as described sequentially.

First, the inner layer 1b will be described. The inner layer 1b is provided between the oxygen barrier layer 1b1 provided on the outer surface side of the container body 2, the inner surface layer 1b2 provided on the inner surface side of the container of the oxygen barrier layer 1b1, and the oxygen barrier layer 1b1 and the inner surface layer 1b2. The adhesive layer 1b3 is provided. By providing the oxygen barrier layer 1b1, the gas barrier property and the peelability from the outer layer 1a can be improved.

The oxygen barrier layer 1b1 is preferably a layer made of an ethylene-vinyl alcohol copolymer (EVOH) resin, and the EVOH resin is obtained by hydrolysis of an ethylene-vinyl acetate copolymer. The ethylene content of the EVOH resin can be, for example, 25 to 50 mol%, but is preferably 32 mol% or less from the viewpoint of oxygen barrier property, and is preferably 25 mol% or more from the viewpoint of flexibility. Further, the EVOH resin preferably contains an oxygen absorber. Thereby, the oxygen barrier property of the oxygen barrier layer 1b1 made of EVOH resin can be further improved.

The inner surface layer 1b2 is a layer that comes into contact with the contents, and depending on the compatibility with the contents and the outer layer 1a, for example, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), high density polyethylene (HDPE). ), Polypropylene (PP), ethylene-propylene copolymer (EPR) and the like.

The adhesive layer 1b3 is a layer having a function of adhering the oxygen barrier layer 1b1 (EVOH layer) and the inner surface layer 1b2. For example, an acid-modified polyolefin in which a carboxyl group is introduced into a polyolefin (eg, maleic anhydride-modified polyethylene) is added. Or ethylene-vinyl acetate copolymer (EVA). An example of the adhesive layer 1b3 is a mixture of low density polyethylene or linear low density polyethylene and acid modified polyethylene.

For the outer layer 1a, a random copolymer can be preferably adopted in consideration of shape restoration, transparency, and heat resistance as an outer shell, depending on the contents, the size of the laminated stripping container 1, and the like. In the present embodiment, the pair of laminated peeling containers 10 and 10'are divided into the split mold 80 when the contents are relatively small such as eye drops and it is not always strongly required to stand upright when not in use. From the viewpoint of ease of removal from the container, it is desired to select a flexible one in which the central burr portion 7 is easily bent.

When the rigidity of the outer layer 1a is high, the central burr portion 7 is not bent by the protruding pin 83, and when the protruding pin 83 is strongly projected, the mouth of the pair of laminated peeling containers 10 and 10'is not the central burr portion 7. The container body 2 such as the portion 4 bends.

Therefore, the present inventors make the inner layer 1b an oxygen barrier layer 1b1 (EVOH layer) / adhesive layer 1b3 / inner surface layer 1b2 (LDPE layer), and then make the outer layer 1a a low-density polyethylene (LDPE), straight chain. By changing to low density polyethylene (LLDPE), high density polyethylene (HDPE), polypropylene (PP), the pair of laminated peeling containers 10 and 10'can be taken out from the split mold 80, and the central burr portion 7 is bent. I investigated the sex. The results are shown in Table 1.

In the investigation, assuming that the laminated peeling container 1 is used as a container for eye drops, the outer layer 1a has an LDPE (here, a flexural modulus of 160 MPa is used) and an LLDPE (also having a flexural modulus of 340 MPa). Four types of materials were selected: HDPE (also used one with a flexural modulus of 1000 MPa), PP (also used one with a flexural modulus of 630 MPa), and the inner layer 1b was used under the same conditions. The take-out property and flexibility were confirmed.

As shown in Table 1, for the laminated structure of the laminated stripping container 1 and the pair of laminated stripping containers 10, 10', at least the outer layer 1a uses a flexible material such as LDPE or LLDPE, that is, a material having a low flexural modulus. It is desirable to do.

Although the present invention has been described above using the embodiments, it goes without saying that the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications or merits can be made to the above embodiments. It is also clear from the description of the claims that the form with such modifications or improvements may be included in the technical scope of the present invention. Further, the present embodiment is particularly preferably used for blow molding, but can also be used for injection molding.

1 ... Laminated peeling container (final molded product)
1a ... Outer layer (outer shell)
1b ... Inner layer (inner bag)
10, 10'... A pair of laminated stripping containers (intermediate molded product)
2 ... Container body 21 ... Parting line 22 ... Pinch portion 22a ... Base portion 22b ... Crimping portion 22c ... Tip portion 3 ... Accommodating portion 31 ... Bottom surface 31a ... Central concave region 31b ... Peripheral region 4 ... Mouth portion 5 ... Shoulder portion 6 ... Body portion 61 ... Bottomed hole 61a ... Air introduction hole 62 ... Recessed portion 7 ... Central burr portions 7a, 7a'... Pair of connecting portions 7b ... Central portion 7c ... Boundary portion 7d ... Contact portion 80 ... Split mold 80a ... 1st template 80b ... 2nd template 81 ... Cavity 82 ... Blow nozzle 83 ... Protruding pin 9 ... Valve member

Claims (2)

A method for manufacturing a pair of laminated stripping containers as an intermediate molded product connected by a central burr portion.
The pair of laminated peeling containers include a first laminated peeling container and a second laminated peeling container located so that the mouths of the first laminated peeling container face each other.
The central burr portion is configured to connect between the mouth portion of the first laminated peeling container and the mouth portion of the second laminated peeling container.
The bottom surface of each of the pair of laminated peeling containers has a central concave region having a raised bottom.
The central burr portion has a thick portion near the center, a mouth portion of the first laminated peeling container, and a thin wall portion near the mouth of the second laminated peeling container, and the wall thickness of the thick portion is The thickness of the thin portion is 1.2 mm to 1.4 mm, and the thickness of the thin portion is 0.7 mm to 0.9 mm.
A step of molding a mold composed of a first mold plate and a second mold plate facing the first mold plate, and
The step of opening the mold and
The central burr portion of the pair of laminated stripping containers left on the first template is projected toward the second template by a protruding pin provided on the back plate of the first template, and the thin wall is formed. A step of bending the central burr portion in the portion is provided.
A manufacturing method characterized in that, in the step of bending the central burr portion, a gap is created between the slope of the central concave region and the corresponding surface of the cavity of the first template. Further, a take-out pin is inserted into an end burr portion attached to a pinch portion provided on the bottom surface of the first laminated peeling container or the second laminated peeling container of the pair of laminated peeling containers, and the pair of laminated strips are used by the protruding pins. The manufacturing method according to claim 1, further comprising a step of taking out the pair of laminated peeling containers from the first mold plate in a state where the central burr portion of the peeling container is projected.

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