JP6643722B2 - Delamination container - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a laminated peeling container in which an inner layer peels from an outer layer and shrinks as the content decreases.

  2. Description of the Related Art Conventionally, there has been known a laminated peeling container that suppresses air from entering the inside of the container by peeling and shrinking of an inner layer from an outer layer as the content decreases (for example, Patent Document 1). Such a laminated peeling container includes an inner bag constituted by an inner layer and an outer shell constituted by an outer layer.

Japanese Patent No. 3563172

  It is said that it is preferable to use a polyethylene resin as the outer layer of the laminated peeling container of Patent Document 1 in order to maintain the external shape of the container.

  However, the present inventor studied that, depending on the method of use and the environment of the delamination container, the shape resilience of the outer shell is not sufficient. In a peeling container, it is desired to improve the shape resilience of the outer shell. Further, such a laminated peeling container is desired to have excellent transparency and heat resistance. However, the laminated peeling container of Patent Document 1 has insufficient transparency and heat resistance depending on the method of use and environment. It turns out that there may be times.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a laminate peeling container excellent in outer shell shape resilience, transparency, and heat resistance.

  According to the present invention, a laminated peeling container comprising an outer layer and an inner layer, wherein the inner layer peels from the outer layer and shrinks as the content decreases, wherein the outer layer is formed between propylene and another monomer. There is provided a laminate release container provided with a propylene copolymer layer composed of a random copolymer.

  The present inventor should improve the shape resilience, transparency and heat resistance of the outer shell, and examined various materials constituting the outer shell, and found that propylene comprising a random copolymer between propylene and another monomer was used. When the outer shell was composed of a copolymer layer, it was discovered that shape resilience, transparency and heat resistance of the outer shell could be improved, and the present invention was completed.

Hereinafter, various embodiments of the present invention will be exemplified. The embodiments described below can be combined with each other.
Preferably, the inner layer includes an EVOH layer made of EVOH, and a melting point of the EVOH is higher than that of the random copolymer.
Preferably, the melting point of the EVOH is at least 15 ° C. higher than the melting point of the random copolymer.
Preferably, the inner layer includes a polyethylene layer on the inner surface side of the container with respect to the EVOH layer via an adhesive layer.

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows the structure of the lamination peeling container 1 of one Embodiment of this invention, (a) is an overall view, (b) shows a bottom part. 1A is a front view, FIG. 1B is a rear view, FIG. 1C is a plan view, and FIG. 1D is a bottom view. It is AA sectional drawing in FIG.2 (d). 1 and 2 show a state before the bottom seal protrusion 27 is bent, and FIG. 3 shows a state after the bottom seal protrusion 27 is bent. FIG. 4 is an enlarged view of a region including a mouth 9 in FIG. 3. 5 shows a state in which the peeling of the inner layer 13 has progressed from the state of FIG. FIG. 4 is an enlarged view of a region including a bottom surface 29 in FIG. 3, (a) illustrates a state before the bottom seal protrusion 27 is bent, and (b) illustrates a state after the bottom seal protrusion 27 is bent. Show. FIG. 3 is a cross-sectional view illustrating a layer configuration of an inner layer 13. FIG. 4 is a perspective view showing various configurations of a valve member 5. 2 shows a manufacturing process of the lamination release container 1 of FIG. 1. 9 shows a step following that of FIG. 9 of the lamination release container 1 of FIG. 1. Another example of the inner layer preliminary peeling / outside air introduction hole forming step is shown. 2 shows a method of using the laminate peeling container 1 of FIG.

  Hereinafter, embodiments of the present invention will be described. Various features shown in the embodiments described below can be combined with each other. Further, the invention is independently realized for each feature.

  As shown in FIG. 1 and FIG. 2, a laminated peeling container 1 according to one embodiment of the present invention includes a container body 3 and a valve member 5. The container body 3 includes a storage section 7 for storing the contents, and an opening 9 for discharging the contents from the storage section 7.

  As shown in FIG. 3, the container body 3 includes an outer layer 11 and an inner layer 13 in the housing portion 7 and the mouth portion 9, and the outer layer 11 forms an outer shell 12, and the inner layer 13 forms an inner bag 14. You. When the inner layer 13 is separated from the outer layer 11 as the content decreases, the inner bag 14 is separated from the outer shell 12 and contracts.

  As shown in FIG. 4, the mouth portion 9 is provided with a male screw portion 9d. A cap or a pump having a female screw is attached to the male screw part 9d. FIG. 4 illustrates a part of the cap 23 having the inner ring 25. The outer diameter of the inner ring 25 is substantially the same as the inner diameter of the mouth portion 9, and leakage of the contents is prevented by the outer surface of the inner ring 25 abutting on the contact surface 9 a of the mouth portion 9. In the present embodiment, the enlarged diameter portion 9b is provided at the tip of the mouth portion 9 and the inner diameter at the enlarged diameter portion 9b is larger than the inner diameter at the contact portion 9e. The outer surface does not contact the enlarged diameter portion 9b. In the case where the enlarged diameter portion 9b is not provided in the mouth portion 9, there is a problem that the inner ring 25 enters between the outer layer 11 and the inner layer 13 when the inner diameter of the mouth portion 9 is slightly reduced due to variation in manufacturing. In some cases, however, such a problem does not occur even when the inside diameter of the mouth 9 slightly varies when the mouth 9 has the enlarged diameter portion 9b.

  In addition, the mouth 9 is provided with an inner layer support 9c at a position closer to the accommodating portion 7 than the abutment 9e to suppress the inner layer 13 from slipping off. The inner layer support portion 9c is formed by providing a constriction in the mouth portion 9. Even when the enlarged diameter portion 9 b is provided in the mouth 9, the inner layer 13 may be separated from the outer layer 11 due to friction between the inner ring 25 and the inner layer 13. In the present embodiment, even in such a case, since the inner layer 13 prevents the inner layer 13 from slipping off, the inner bag 14 can be prevented from falling into the outer shell 12.

  As shown in FIGS. 3 to 5, the housing portion 7 includes a body portion 19 having a substantially constant cross-sectional shape in the longitudinal direction of the housing portion, and a shoulder portion 17 connecting the body portion 19 and the mouth portion 9. Is provided. The shoulder portion 17 is provided with a bent portion 21. The bent portion 21 is a portion where the bending angle α shown in FIG. 3 is 140 degrees or less and the radius of curvature on the inner surface side of the container is 4 mm or less. In the case where the bent portion 21 is not provided, the separation between the inner layer 13 and the outer layer 11 spreads from the trunk portion 19 to the mouth 9, and the inner layer 13 and the outer layer 11 may be peeled at the mouth 9. However, peeling of the inner layer 13 and the outer layer 11 at the mouth 9 causes the inner bag 14 to fall into the outer shell 12, so that peeling of the inner layer 13 and the outer layer 11 at the mouth 9 is not desirable. In the present embodiment, since the bent portion 21 is provided, when the separation between the inner layer 13 and the outer layer 11 spreads from the body portion 19 to the bent portion 21, the inner layer 13 is bent at the bent portion 21 as shown in FIG. As a result, the force for separating the inner layer 13 from the outer layer 11 is not transmitted to the upper portion of the bent portion 21. As a result, the separation between the inner layer 13 and the outer layer 11 in the portion above the bent portion 21 is suppressed. You. In addition, although the bent part 21 is provided in the shoulder part 17 in FIGS. 3-5, the bent part 21 may be provided in the boundary of the shoulder part 17 and the trunk | drum 19. FIG.

The lower limit of the bending angle α is not particularly limited, but is preferably 90 degrees or more in consideration of ease of manufacture. The lower limit of the radius of curvature is not particularly limited, but is preferably 0.2 mm or more in view of ease of production. Further, in order to more reliably prevent separation of the inner layer 13 and the outer layer 11 at the opening 9, the bending angle α is preferably 120 degrees or less, and the radius of curvature is preferably 2 mm or less. The bending angle α is, for example, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140 degrees, and is within a range between any two of the numerical values exemplified here. It may be. The radius of curvature is specifically, for example, 0.2, 0.4, 0.6, 0.8, 1, 1.2, 1.4, 1.6, 1.8, 2 mm, where It may be in the range between any two of the exemplified values.

  As shown in FIG. 4, in the bent portion 21, the distance L2 from the container center axis C to the inner surface of the container at the bent portion 21 is 1.3 times the distance L1 from the container center axis C to the inner surface of the container at the mouth 9. It is provided at a position that is twice or more. The laminate peeling container 1 of the present embodiment is formed by blow molding. As the ratio L2 / L1 increases, the blow ratio at the bent portion 21 increases and the wall thickness decreases, so that L2 / L1 ≧ 1. By setting 3, the thickness of the inner layer 13 at the bent portion 21 becomes sufficiently thin, the inner layer 13 is more easily bent at the bent portion 21, and the separation of the inner layer 13 and the outer layer 11 at the mouth 9 is more reliably performed. Is prevented. L2 / L1 is, for example, 1.3 to 3, and preferably 1.4 to 2. L2 / L1 is specifically, for example, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.5, 3, and here. May be in the range between any two of the numerical values exemplified in the above.

  In one example, the thickness at the mouth 9 is 0.45 to 0.50 mm, the thickness at the bent portion 21 is 0.25 to 0.30 mm, and the thickness at the trunk 19 is 0 to 0.50 mm. .15 to 0.20 mm. As described above, since the thickness of the bent portion 21 is sufficiently smaller than the thickness of the mouth portion 9, the bent portion 21 effectively exerts its function.

  By the way, as shown in FIG. 4, the housing member 7 has a valve member 5 for adjusting the air flow between the intermediate space 21 between the outer shell 12 and the inner bag 14 and the outer space S of the container body 3. Is provided. The outer shell 12 is provided with an outside air introduction hole 15 that communicates the intermediate space 21 and the external space S in the housing 7. The outside air introduction hole 15 is a through hole provided only in the outer shell 12 and does not reach the inner bag 14. The valve member 5 is provided in the intermediate space 21 side of the shaft portion 5a which is inserted into the outside air introduction hole 15 and is slidable with respect to the outside air introduction hole 15, and has a larger sectional area than the shaft portion 5a. A lid 5c and a locking portion 5b provided on the outer space S side of the shaft 5a and preventing the valve member 5 from entering the intermediate space 21 are provided.

  The lid 5c is configured to substantially close the outside air introduction hole 15 when the outer shell 12 is compressed, and has a shape whose cross-sectional area decreases as approaching the shaft 5a. The locking portion 5b is configured such that air can be introduced into the intermediate space 21 when the outer shell 12 is restored after being compressed. When the outer shell 12 is compressed, the pressure in the intermediate space 21 becomes higher than the external pressure, and the air in the intermediate space 21 leaks from the outside air introduction hole 15 to the outside. The lid portion 5c moves toward the outside air introduction hole 15 due to the pressure difference and the flow of air, and the lid portion 5c closes the outside air introduction hole 15. Since the lid 5c has a shape in which the cross-sectional area becomes smaller as approaching the shaft 5a, the lid 5c easily fits into the outside air introduction hole 15 and closes the outside air introduction hole 15.

  When the outer shell 12 is further compressed in this state, the pressure in the intermediate space 21 increases, and as a result, the inner bag 14 is compressed, and the contents in the inner bag 14 are discharged. When the compressive force on the outer shell 12 is released, the outer shell 12 tries to restore its own elasticity. At this time, the lid 5c is separated from the outside air introduction hole 15, the blockage of the outside air introduction hole 15 is released, and outside air is introduced into the intermediate space 21. In order to prevent the locking portion 5b from blocking the outside air introduction hole 15, the locking portion 5b is provided with a projection 5d at a portion which comes into contact with the outer shell 12, and the projection 5d comes into contact with the outer shell 12. Thereby, a gap is provided between the outer shell 12 and the locking portion 5b. Instead of providing the protrusion 5d, a groove may be provided in the locking portion 5b to prevent the locking portion 5b from closing the outside air introduction hole 15. FIG. 8 shows a specific example of the configuration of the valve member 5.

  The valve member 5 can be mounted on the container body 3 by being inserted into the intermediate space 21 into the lid 5c while the lid 5c pushes and widens the outside air introduction hole 15. For this reason, it is preferable that the tip of the lid 5c be tapered. Since such a valve member 5 can be mounted simply by pushing the lid 5c into the intermediate space 21 from the outside of the container main body 3, the productivity is excellent.

  The housing 7 is covered with a shrink film after the valve member 5 is attached. At this time, the valve member 5 is mounted in the valve member mounting recessed portion 7a provided in the housing portion 7 so that the valve member 5 does not interfere with the shrink film. Further, an air flow groove 7b extending from the valve member mounting recess 7a toward the opening 9 is provided so that the valve member mounting recess 7a is not sealed by the shrink film.

  As shown in FIG. 1 (b), a central concave region 29 a and a peripheral region 29 b provided around the central concave region 29 a are provided on the bottom surface 29 of the housing portion 7, and the central concave region 29 a has a bottom projecting from the bottom surface 29. A seal projection 27 is provided. As shown in FIGS. 6A and 6B, the bottom seal protrusion 27 is a seal portion of the laminated parison in blow molding using a cylindrical laminated parison having the outer layer 11 and the inner layer 13. The bottom seal protruding portion 27 includes a base portion 27d, a thin portion 27a, and a thick portion 27b having a greater thickness than the thin portion 27a in order from the bottom surface 29 side.

  Immediately after blow molding, as shown in FIG. 6A, the bottom seal protrusion 27 is in a state of standing substantially perpendicular to a plane P defined by the peripheral region 29b. When an impact is applied to the container, the inner layers 13 in the welded portion 27c are easily separated from each other, and the impact resistance is insufficient. Therefore, in the present embodiment, the thin portion 27a is softened by blowing hot air to the bottom seal protrusion 27 after blow molding, and the bottom seal protrusion 27 is bent at the thin portion 27a as shown in FIG. 6B. I have. As described above, the impact resistance of the bottom seal protrusion 27 is improved by a simple process of simply bending the bottom seal protrusion 27. Further, as shown in FIG. 6B, the bottom seal protrusion 27 does not protrude from the plane P defined by the peripheral region 29b in a bent state. This prevents the bottom seal protruding portion 27 from protruding from the surface P when the stacking and peeling container 1 is set up, and prevents the stacking and peeling container 1 from shaking.

  The base portion 27d is provided on the bottom surface 29 side of the thin portion 27a and is thicker than the thin portion 27a. The base portion 27d may be omitted, but the thin portion 27a is provided on the base portion 27d. The impact resistance of the bottom seal protruding portion 27 can be further improved.

  Further, as shown in FIG. 1B, the concave region of the bottom surface 29 is provided so as to cross the entire bottom surface 29 in the longitudinal direction of the bottom seal protrusion 27. That is, the central concave region 29a and the peripheral edge concave region 29c are connected. With such a configuration, the bottom seal protrusion 27 is easily bent.

  Next, the layer configuration of the container body 3 will be described in more detail. The container body 3 includes an outer layer 11 and an inner layer 13.

  The outer layer 11 is made of, for example, low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymer, and a mixture thereof. The outer layer 11 may have a multilayer structure. For example, a configuration in which both sides of the repro layer are sandwiched between polypropylene layers may be employed. Here, the term “repro layer” refers to a layer obtained by recycling burrs generated during molding of a container. Further, the outer layer 11 is formed thicker than the inner layer 13 so as to increase the resilience.

  In the present embodiment, the outer layer 11 includes a random copolymer layer made of a random copolymer between propylene and another monomer. The outer layer 11 may be a single layer of a random copolymer layer, or may have a multilayer structure. For example, a configuration in which both sides of the repro layer are sandwiched between random copolymer layers may be employed. By configuring the outer layer 11 with a random copolymer having a specific configuration, the shape resilience, transparency, and heat resistance of the outer shell 12 can be improved.

  The content of the monomer other than propylene in the random copolymer is smaller than 50 mol%, and preferably 5 to 35 mol%. This content is specifically, for example, 5, 10, 15, 20, 25, or 30 mol%, and may be in a range between any two of the numerical values exemplified here. As the monomer to be copolymerized with propylene, any monomer may be used as long as it improves the impact resistance of the random copolymer as compared with a homopolymer of polypropylene, and ethylene is particularly preferable. In the case of a random copolymer of propylene and ethylene, the content of ethylene is preferably 5 to 30 mol%, specifically, for example, 5, 10, 15, 20, 25, and 30 mol%. May be in the range between any two. The weight average molecular weight of the random copolymer is preferably from 100,000 to 500,000, more preferably from 100,000 to 300,000. The weight average molecular weight is specifically, for example, 10, 15, 20, 25, 30, 35, 40, 45, or 500,000, and is in a range between any two of the numerical values exemplified here. Is also good.

Further, the tensile modulus of the random copolymer is preferably from 400 to 1600 MPa, more preferably from 1,000 to 1600 MPa. This is because when the tensile modulus is in such a range, the shape restoring property is particularly good. Specifically, the tensile modulus is, for example, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600 Mpa, and is between any two of the numerical values exemplified here. May be within the range.
If the container is excessively hard, the feeling of use of the container deteriorates. Therefore, the outer layer 11 may be formed by mixing a soft material such as linear low-density polyethylene with the random copolymer. However, the material to be mixed with the random copolymer is preferably mixed so as to be less than 50% by weight with respect to the whole mixture so as not to significantly impair the effective properties of the random copolymer. For example, the outer layer 11 can be composed of a material in which a random copolymer and a linear low-density polyethylene are mixed at a weight ratio of 85:15.

  As shown in FIG. 7, the inner layer 13 is provided with an EVOH layer 13a provided on the outer surface of the container, an inner layer 13b provided on the inner surface of the container of the EVOH layer 13a, and provided between the EVOH layer 13a and the inner layer 13b. The adhesive layer 13c provided. By providing the EVOH layer 13a, the gas barrier properties and the releasability from the outer layer 11 can be improved.

  The EVOH layer 13a is a layer made of an ethylene-vinyl alcohol copolymer (EVOH) resin, and is obtained by hydrolysis of an ethylene-vinyl acetate copolymer. The ethylene content of the EVOH resin is, for example, 25 to 50 mol%, and is preferably 32 mol% or less from the viewpoint of oxygen barrier properties. Although the lower limit of the ethylene content is not particularly limited, the lower the ethylene content, the more the flexibility of the EVOH layer 13a is likely to be reduced. Further, the EVOH layer 13a preferably contains an oxygen absorbent. By including the oxygen absorber in the EVOH layer 13a, the oxygen barrier property of the EVOH layer 13a can be further improved. The flexural modulus of the EVOH resin is preferably 2350 MPa or less, more preferably 2250 MPa or less. The lower limit of the flexural modulus of the EVOH resin is not particularly limited, but is, for example, 1800, 1900, or 2000 MPa. The flexural modulus can be measured by a test method based on ISO178. The test speed is 2 mm / min.

  The melting point of the EVOH resin is preferably higher than the melting point of the random copolymer forming the outer layer 11. The outside air introduction hole 15 is preferably formed in the outer layer 11 using a heating type perforation device. However, by setting the melting point of the EVOH resin higher than the melting point of the random copolymer, the outside air introduction hole 15 is formed in the outer layer 11. During formation, holes are prevented from reaching the inner layer 13. From this viewpoint, the difference between (the melting point of EVOH) and (the melting point of the random copolymer layer) is preferably large, and is preferably 15 ° C. or more, and particularly preferably 30 ° C. or more. The difference between the melting points is, for example, 5 to 50 ° C., specifically, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, and 50 ° C. Or between the two.

  The inner surface layer 13b is a layer that comes into contact with the contents of the laminated peeling container 1, and includes, for example, polyolefin such as low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymer, and a mixture thereof. And low-density polyethylene or linear low-density polyethylene. The tensile modulus of the resin constituting the inner surface layer 13b is preferably from 50 to 300 MPa, and more preferably from 70 to 200 MPa. This is because when the tensile modulus is in such a range, the inner surface layer 13b is particularly flexible. The tensile modulus is specifically, for example, specifically, for example, 50, 100, 150, 200, 250, or 300 Mpa, and may be in a range between any two of the numerical values exemplified here. .

  The adhesive layer 13c is a layer having a function of bonding the EVOH layer 13a and the inner surface layer 13b. For example, the adhesive layer 13c is obtained by adding an acid-modified polyolefin obtained by introducing a carboxyl group to the above-described polyolefin (eg, maleic anhydride-modified polyethylene). , Ethylene-vinyl acetate copolymer (EVA). One example of the adhesive layer 13c is a mixture of low-density polyethylene or linear low-density polyethylene and acid-modified polyethylene.

Next, an example of a method for manufacturing the laminated peeling container 1 of the present embodiment will be described.
First, as shown in FIG. 9A, a laminated structure corresponding to the container body 3 to be manufactured (an example is a PE layer / adhesive layer / EVOH layer in this order from the container inner surface side as shown in FIG. 9A). (Laminated structure of / PP layer) in a molten state is extruded, the laminated parison in the molten state is set in a blow mold, and the split mold is closed.
Next, as shown in FIG. 9B, a blow nozzle is inserted into the opening on the side of the opening 9 of the container body 3, and air is blown into the cavity of the split mold while the mold is clamped.

  Next, as shown in FIG. 9C, the split mold is opened, and the blow molded product is taken out. The split mold has a cavity shape such that various shapes of the container body 3 such as the valve member mounting recess 7a, the air flow groove 7b, and the bottom seal protrusion 27 are formed in a blow molded product. In addition, the split mold is provided with a pinch-off portion below the bottom seal protrusion 27, and a lower burr is formed below the bottom seal protrusion 27, so that this is removed.

Next, as shown in FIG. 9D, the blow-molded products taken out are aligned.
Next, as shown in FIG. 9 (e), a hole is made only in the outer layer 11 in the upper cylindrical portion 31 provided above the mouth 9, and a blower 33 is used between the outer layer 11 and the inner layer 13. By blowing air, the inner layer 13 is preliminarily peeled off from the outer layer 11 at the portion of the housing 7 where the valve member 5 is mounted (the valve member mounting recess 7a). This preliminary peeling facilitates the step of forming the outside air introduction hole 15 and the step of mounting the valve member 5. The distal end of the upper tubular portion 31 may be covered with a cover member so that the blown air does not leak from the distal end of the upper tubular portion 31. In addition, in order to easily make a hole only in the outer layer 11, the inner layer 13 may be peeled from the outer layer 11 in the upper tubular part 31 by crushing the upper tubular part 31 before making a hole. The preliminary peeling may be performed on the entirety of the storage unit 7 or on a part of the storage unit 7.
Next, as shown in FIG. 9 (f), an outside air introduction hole 15 is formed in the outer shell 12 using a drilling device. The outside air introduction hole 15 is preferably a round hole, but may have another shape.
Next, as shown in FIG. 10A, the thin portion 27a is softened by applying hot air to the bottom seal protrusion 27, and the bottom seal protrusion 27 is bent.
Next, the valve member 5 is inserted into the outside air introduction hole 15 as shown in FIG.
Next, as shown in FIG. 10C, the upper cylindrical portion 31 is cut.
Next, as shown in FIG. 10 (d), the inner bag 14 is inflated by blowing air into the inner bag 14.
Next, as shown in FIG. 10E, the inner bag 14 is filled with contents.
Next, as shown in FIG. 10F, a cap 23 is attached to the mouth 9.
Next, as shown in FIG. 10 (g), the accommodating portion 7 is covered with a shrink film, and a product is completed.

  The order of the various steps shown here can be changed as appropriate. For example, the hot air bending step may be performed before the outside air introduction hole opening step or before the inner layer preliminary peeling step. Further, the step of cutting the upper cylindrical portion 31 may be performed before the valve member 5 is inserted into the outside air introduction hole 15.

Further, the inner layer preliminary peeling and the outside air introduction hole opening step can also be performed by the following method.
First, as shown in FIG. 11A, the air in the inner bag 14 is sucked from the mouth 9 to reduce the pressure in the inner bag 14. In this state, a piercing device such as a heat pipe or a pipe cutter is slowly pressed against the outer layer 11. This perforation device has a cylindrical cutter, and air inside the cylinder is sucked. When no hole is formed in the outer layer 11, no air enters between the outer layer 11 and the inner layer 13, so that the inner layer 13 is not separated from the outer layer 11.

  When the cylindrical cutter penetrates the outer layer 11, as shown in FIG. 11 (b), the cut-out cut-out piece is removed through the inside of the cylindrical cutter, and the outside air introduction hole 15 is formed. At this moment, air enters between the outer layer 11 and the inner layer 13, and the inner layer 13 is separated from the outer layer 11.

  Next, as shown in FIG. 11 (c), the diameter of the outside air introduction hole 15 is expanded using a drilling device. In the case of forming the outside air introduction hole 15 large enough to insert the valve member 5 in the steps of FIGS. 11A and 11B, the diameter expanding step of FIG. 11C is unnecessary.

Next, the principle of operation when the manufactured product is used will be described.
As shown in FIGS. 12 (a) to 12 (c), the product filled with the content is compressed while holding the side surface of the outer shell 12 in a tilted state to discharge the content. At the start of use, since there is substantially no gap between the inner bag 14 and the outer shell 12, the compression force applied to the outer shell 12 becomes the compression force of the inner bag 14 as it is, and the inner bag 14 is compressed. Then, the contents are discharged.

  The cap 23 has a built-in check valve (not shown) and can discharge the contents in the inner bag 14, but cannot take outside air into the inner bag 14. Therefore, if the compressive force applied to the outer shell 12 after the discharge of the contents is removed, the outer shell 12 tries to return to its original shape by its own restoring force, but only the outer shell 12 remains with the inner bag 14 deflated. Will expand. Then, as shown in FIG. 12D, the pressure in the intermediate space 21 between the inner bag 14 and the outer shell 12 is reduced, and the outside air is introduced into the intermediate space 21 through the outer air introduction hole 15 formed in the outer shell 12. be introduced. When the intermediate space 21 is in a depressurized state, the lid 5c is not pressed against the outside air introduction hole 15 and does not hinder the introduction of outside air. Further, the engaging portion 5b is provided with an airway securing means such as a protrusion 5d or a groove so that the engaging portion 5b does not prevent the introduction of the outside air even when the engaging portion 5b is in contact with the outer shell 12.

  Next, as shown in FIG. 12 (e), when the outer shell 12 is once again gripped and compressed, the lid 5 c closes the outside air introduction hole 15, so that the pressure in the intermediate space 21 increases, The compressive force applied to the outer shell 12 is transmitted to the inner bag 14 via the intermediate space 21, and the inner bag 14 is compressed by this force to discharge the contents.

  Next, as shown in FIG. 12 (f), when the compressive force applied to the outer shell 12 after discharging the contents is removed, the outer shell 12 introduces outside air into the intermediate space 21 from the outside air introduction hole 15. Is restored to its original shape by its own restoring force.

  In the following Examples and Comparative Examples, various laminated release containers having different layer configurations were manufactured by blow molding, and the resilience, rigidity, impact resistance, heat resistance, transparency, gas barrier properties, moldability, outer layer workability, etc. Were evaluated. The outer layer workability indicates the ease of processing in which an outside air introduction hole is formed only in the outer layer using a heating type punch.

<Example 1>
In Example 1, the layer configuration was, in order from the outside of the container, a random copolymer layer / EVOH layer / adhesive layer / LLDPE layer. For the random copolymer layer, a random copolymer of propylene and ethylene (model: Novatec EG7FTB, manufactured by Nippon Polypropylene Corporation, melting point 150 ° C.) was used. For the EVOH layer, high melting point EVOH (model: Soarnol SF7503B, manufactured by Nippon Synthetic Chemical Co., Ltd., melting point: 188 ° C., flexural modulus: 2190 MPa) was used. When the above various evaluations were performed, excellent results were obtained for all the evaluation items.

<Example 2>
In Example 2, the layer configuration was, in order from the outside of the container, a random copolymer layer / repro layer / random copolymer layer / EVOH layer / adhesive layer / LLDPE layer. The repro layer is made of a material obtained by recycling burrs formed at the time of forming the container, and has a composition very close to that of the random copolymer layer. The random copolymer layer and the EVOH layer were formed of the same materials as in Example 1. When the above various evaluations were performed, excellent results were obtained for all the evaluation items.

<Example 3>
In Example 3, the layer configuration was the same as that in Example 1, but a low melting point EVOH (model: Soarnol A4412, manufactured by Nippon Synthetic Chemical Co., melting point: 164 ° C.) was used for the EVOH layer. When the above various evaluations were performed, excellent results were obtained in all the evaluation items other than the outer layer workability, but the outer layer workability was slightly inferior to Example 1. This result demonstrates that the difference of (melting point of EVOH) − (melting point of random copolymer layer) is preferably 15 ° C. or more.

<Comparative Example 1>
In Comparative Example 1, the layer configuration was, in order from the outside of the container, an LDPE layer / EVOH layer / adhesive layer / LLDPE layer. As a result of the various evaluations described above, at least rigidity and heat resistance were low.

<Comparative Example 2>
In Comparative Example 2, the layer configuration was, in order from the outside of the container, an HDPE layer / EVOH layer / adhesive layer / LLDPE layer. As a result of the various evaluations described above, at least the resilience and the transparency were low.

<Comparative Example 3>
In Comparative Example 3, the layer configuration was, in order from the outside of the container, a polypropylene layer / EVOH layer / adhesive layer / LLDPE layer. As the material of the polypropylene layer, a homopolymer of propylene having a melting point of 160 ° C. was used. The same material as in Example 1 was used for the EVOH layer. When the above various evaluations were performed, at least the impact resistance was low. Further, the outer layer workability was inferior to Example 1.

<Comparative Example 4>
In Comparative Example 4, the layer configuration was, in order from the outside of the container, a block copolymer layer / EVOH layer / adhesive layer / LLDPE layer. As a result of the various evaluations described above, at least the transparency and the impact resistance were low.

<Comparative Example 5>
In Comparative Example 5, the layer configuration was PET layer / EVOH layer / adhesive layer / LLDPE layer in order from the outside of the container. When the above various evaluations were performed, at least the moldability and heat resistance were low.

<Comparative Example 6>
In Comparative Example 6, the layer configuration was, in order from the outside of the container, a polyamide layer / EVOH layer / adhesive layer / LLDPE layer. When the above various evaluations were performed, at least the moldability was low.

<Comparative Example 7>
In Comparative Example 6, the layer configuration was, in order from the outside of the container, a polypropylene layer / polyamide layer / adhesive layer / LLDPE layer. When the above various evaluations were performed, at least the gas barrier properties and the moldability were low.

<Bending resistance test>
The EVOH resin used as the EVOH layer was subjected to a bending resistance test using a gelbo flex tester (manufactured by Brugger, KFT-C-Flex Durability Tester) compliant with ASTM F392. The test environment was 23 ° C. and 50% RH.
First, a sample composed of a single-layer film of 28 cm × 19 cm × 30 μm was prepared.
Next, both ends of the sample were fixed to the pair of mandrels A and B by winding the long side of the sample around a pair of mandrels (diameter 90 mm) arranged at an interval of 180 mm.
Next, the mandrel B was gradually approached while being twisted while the mandrel A was fixed, and the twisting was stopped when the twisting angle was 440 degrees and the horizontal movement distance was 9.98 cm. Thereafter, the horizontal movement of the mandrel B was continued, and when the horizontal movement distance after stopping the twisting became 6.35 cm, the horizontal movement was stopped. Thereafter, the mandrel B was returned to the initial state by the reverse operation. After performing such an operation 100 times, the presence or absence of a pinhole was examined. Table 1 shows the results.

  SF7503B in Table 1 is an EVOH resin used as the EVOH layer in Example 1. On the other hand, D2908 in Table 1 is Soarnol D2908 (model: Soarnol SF7503B, manufactured by Nippon Synthetic Chemical Company) and is a general EVOH resin. Each EVOH resin was tested twice.

  As shown in Table 1, the above test revealed that D2908 had many pinholes, whereas SF7503B had no pinholes at all, and was superior in bending resistance to general EVOH resin. I understood that.

1: laminated peeling container, 3: container body, 5: valve member, 7: housing, 9: mouth, 11: outer layer, 12: outer shell, 13: inner layer, 14: inner bag, 15: outside air introduction hole, 23: cap, 27: bottom seal protrusion

Claims (5)

An outer layer and an inner layer, a laminate peeling container in which the inner bag formed by the inner layer shrinks with a decrease in contents,
An outer shell formed by the outer layer is provided with an outside air introduction hole,
The laminated peeling container is configured to prevent leakage of air through the outside air introduction hole when the outer shell is compressed,
The outer layer includes a random copolymer layer composed of a random copolymer between propylene and another monomer,
The inner layer, EVOH and the EVOH layer and an outermost layer Ri Tona, comprising an inner layer via an adhesive layer on the inner surface of the container side than the EVOH layer,
The inner surface layer is made of linear low-density polyethylene,
The laminated peeling container, wherein the adhesive layer contains an acid-modified polyethylene.   The laminate peeling container according to claim 1, wherein the adhesive layer comprises a mixture of the acid-modified polyethylene and a linear low-density polyethylene.   The delamination container according to claim 1 or 2, wherein the outer layer includes a repro layer that is formed by recycling burrs formed during molding of the delamination container. An outer layer and an inner layer, a laminate peeling container in which the inner bag formed by the inner layer shrinks with a decrease in contents,
An outer shell formed by the outer layer is provided with an outside air introduction hole,
The laminate peeling container is configured to prevent leakage of air through the outside air introduction hole when the outer shell is compressed,
The inner layer includes an EVOH layer made of EVOH,
The lamination release container, wherein the outer layer includes a repro layer formed by recycling burrs formed at the time of molding the lamination release container, and a polypropylene layer on both sides thereof .   The laminate peeling container according to any one of claims 1 to 4, wherein the EVOH has an ethylene content of 32 mol% or less.