JP7104875B2 - double container - Google Patents

Description

TECHNICAL FIELD The present invention relates to a double container in which the inner layer shrinks as the contents are discharged, and more particularly to a new double container designed to prevent the unintentional separation of the outer layer and the inner layer at the mouth. be.

Conventionally, there is an air gap between a container body having an outer layer container and an inner bag, the inner bag shrinking as the contents decrease, and an intermediate space between the outer layer container and the inner bag and the outer space of the container body. A double container (so-called delamination container) provided with a check valve for adjusting inflow and outflow is known (see, for example, Patent Documents 1 and 2).

In the delamination container disclosed in Patent Literature 1, a valve is incorporated in a cap attached to the mouth of the container body. In the delaminating container disclosed in Patent Document 2, a valve is provided inside the body of the outer shell.

JP 2013-35557 A JP-A-4-267727

By the way, this type of double container is manufactured by extruding a laminated parison in a melted state and blow-molding it. Cutting of this unnecessary portion is generally performed using a knife.

In this case, the cut end face of the outer layer and the cut end face of the inner layer are exposed at the tip of the opening of the double container cut by the knife. At the tip of the opening where the end faces of the laminated outer layer and inner layer are exposed, the inner layer may be unintentionally peeled off from the outer layer, which is a factor that impairs the quality and reliability of the double container. . In particular, in pump-type double containers, the inner layer of the mouth part may turn up or fall off due to interference when inserting the filling nozzle or pump, friction with packing when tightening the pump, negative pressure inside the container when the pump is operating, etc. There is a risk of If the inner layer peels off at the mouth, the contents may enter between the outer layer and the inner layer, and if the contents do enter, problems such as leakage from the outside air introduction hole may occur.

The present invention has been made in view of such conventional circumstances, and it is an object of the present invention to provide a double-layered container of high quality and reliability in which the outer layer and the inner layer do not unintentionally separate from each other at the tip of the opening. aim.

In order to achieve the above object, the double container of the present invention has an outer layer and an inner layer, wherein the inner layer shrinks as the content stored in the inner layer decreases, and the double container has a mouth. end surfaces of the outer layer and the inner layer are exposed at the tip of the mouth, the tip of the mouth is enlarged in diameter, the outer layer and the inner layer are inclined, a protective member is attached to the tip of the mouth, and the The protective member has a rib contacting the inner peripheral surface of the inner layer at the tip of the mouth portion, and is mounted by press-fitting. characterized by being worn by Alternatively, a double container having an outer layer and an inner layer, wherein the inner layer shrinks as the content stored in the inner layer decreases, wherein the end surfaces of the outer layer and the inner layer are exposed at the tip of the mouth. a protective member is attached to the tip of the mouth portion, the protection member is an annular member, and is welded to the tip of the mouth portion; It is characterized by being mounted by screwing through .

In a state in which the end surfaces of the outer layer and the inner layer are exposed at the tip of the mouth portion, even a slight external force may cause the inner layer to separate from the outer layer. Delamination of the outer and inner layers at the mouth tip can also trigger further delamination. In the double container of the present invention, since the protective member is attached to the tip of the opening, peeling of the outer layer and the inner layer is reliably suppressed.

According to the present invention, it is possible to provide a double container with high quality and reliability without the outer layer and the inner layer peeling off at the tip of the mouth portion.

It is a perspective view showing an example of a double container. It is a schematic perspective view of a container main body. It is a principal part schematic sectional drawing of a container main body. It is a schematic sectional drawing which shows the layer structure of an outer layer and an inner layer. It is a figure which shows the usage method of a double container. FIG. 10 is a view showing the vicinity of the mouth of the double container, where (A) is a schematic perspective view showing a state before attachment of the ring-shaped protective member, and (B) is a schematic perspective view showing a welded state of the ring-shaped protective member. and (C) are schematic cross-sectional views showing the welded state of the ring-shaped protective member. FIG. 4 is a schematic cross-sectional view of a main part showing a state in which a cap is attached to the double container; FIG. 4 is an exploded perspective view showing how the pump is attached to the double container; FIG. 4 is a schematic cross-sectional view of a main part showing how the pump is attached to the double container; FIG. 4 is a view showing the vicinity of the mouth of the double container, where (A) is a schematic perspective view showing the state before the disk-shaped protective member is attached, and (B) is a schematic showing the welding state of the disk-shaped protective member. FIG. 2C is a perspective view, and FIG. 4C is a schematic cross-sectional view showing a welded state of a disk-shaped protective member; FIG. 4 is a view showing the vicinity of the mouth of the double container, (A) is a schematic perspective view showing a state before mounting a ring-shaped protective member having ribs (sleeves), and (B) is a ring-shaped protective member having ribs. FIG. 3C is a schematic perspective view showing a mounting state of the member, and (C) is a schematic cross-sectional view showing a mounting state of a ring-shaped protective member having ribs. FIG. 2 is a schematic cross-sectional view of a main part showing a configuration in which a ring-shaped protective member having ribs (sleeves) is applied to a pump-type double container. FIG. 4 is an exploded perspective view showing a state where a ring-shaped protective member is attached to a double container having an enlarged tip end. FIG. 10 is a view showing the vicinity of the mouth of the double container, where (A) is a schematic perspective view showing a state before attachment of the ring-shaped protective member, and (B) is a schematic perspective view showing a welded state of the ring-shaped protective member. is.

EMBODIMENT OF THE INVENTION Hereafter, embodiment of the double container to which this invention is applied is described with reference to drawings.

As shown in FIGS. 1 to 3, the double container 1 of the present embodiment is mainly composed of a container body 2, and the container body 2 includes a storage portion 3 for storing contents, and a container from the storage portion 3. It has an opening 4 for discharging the contents. A cap 30 is attached to the mouth portion 4 of the container body 2 .

The double container 1 of the present embodiment is a so-called delamination container, and as shown in FIG. 12, the inner layer 12 shrinks as the contents decrease.

The outer layer 11 and the inner layer 12 are subjected to blow molding as a multi-layer parison and molded in an integrally bonded state. is peeled off, and the contents are filled until the inner layer 12 is in contact with the outer layer 11 . By pushing out the contents, the inner layer 12 shrinks smoothly. Alternatively, the inner layer 12 may remain bonded to the outer layer 11, and the inner layer 12 may be peeled off from the outer layer 11 and contracted as the contents are discharged.

The layer structure of the container body 2 will be further described. there is

The outer layer 11 is made of, for example, low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymer and mixtures thereof. The outer layer 11 has a single-layer or multi-layer structure, and preferably contains a lubricant in at least one of the innermost layer and the outermost layer. When the outer layer 11 has a single-layer structure, the single layer is the innermost layer and the outermost layer, so that layer may contain a lubricant. When the outer layer 11 has a two-layer structure, the layer on the inner surface side of the container is the innermost layer and the layer on the outer surface side of the container is the outermost layer, so at least one of them may contain a lubricant. When the outer layer 11 is composed of three or more layers, the layer closest to the inner surface of the container is the innermost layer, and the layer closest to the outer surface of the container is the outermost layer.

As shown in FIG. 4, the outer layer 11 preferably has a repro layer 11c between the innermost layer 11b and the outermost layer 11a. The repro layer is a layer made by recycling burrs generated during the molding of the container. When the outer layer 11 has a multilayer structure, it is preferable that both the innermost layer and the outermost layer contain a lubricant.

As the lubricant, those generally available on the market can be used, and any of hydrocarbon, fatty acid, aliphatic amide, and metal soap may be used. good. Hydrocarbon-based lubricants include liquid paraffin, paraffin wax, synthetic polyethylene wax, and the like. Fatty acid-based lubricants include stearic acid and stearyl alcohol. Fatty acid amides such as stearic acid amide, oleic acid amide and erucic acid amide, and alkylene fatty acid amides such as methylenebisstearic acid amide and ethylenebisstearic acid amide can be used as the aliphatic amide lubricant. Examples of metal soap-based lubricants include metal stearates.

The innermost layer of the outer layer 11 is in contact with the inner layer 12, and the release property between the outer layer 11 and the inner layer 12 can be improved by incorporating a lubricant into the innermost layer of the outer layer 11. On the other hand, the outermost layer of the outer layer 11 is a layer that comes into contact with the mold during blow molding, and the releasability can be improved by incorporating a lubricant into the outermost layer of the outer layer 11 .

One or both of the innermost layer and the outermost layer of the outer layer 11 can be formed of a random copolymer between propylene and another monomer. As a result, the shape restorability, transparency, and heat resistance of the outer layer 11, which is the outer shell, can be improved.

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

Further, the tensile elastic modulus of the random copolymer is preferably 400-1600 MPa, more preferably 1000-1600 MPa. This is because, when the tensile modulus is within 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, 1600Mpa, between any two of the numerical values illustrated here may be within the range of

If the container is excessively hard, the feeling of use of the container is poor. Therefore, the outer layer 11 may be formed by mixing a flexible material such as linear low-density polyethylene into the random copolymer. However, the material to be mixed with the random copolymer is preferably mixed in an amount of less than 50% by weight based on the entire mixture so as not to significantly impair the effective properties of the random copolymer. For example, the outer layer 11 can be made of a material in which a random copolymer and linear low-density polyethylene are mixed at a weight ratio of 85:15.

As shown in FIG. 4, the inner layer 12 includes an EVOH layer 12a provided on the outer surface side of the container, an inner layer 12b provided on the inner surface side of the container of the EVOH layer 12a, and provided between the EVOH layer 12a and the inner surface layer 12b. and an adhesive layer 12c. By providing the EVOH layer 12a, the gas barrier properties and the peelability from the outer layer 11 can be improved.

The EVOH layer 12a is a layer made of ethylene-vinyl alcohol copolymer (EVOH) resin and obtained by hydrolysis of ethylene and vinyl acetate copolymer. The ethylene content of the EVOH resin is, for example, 25 to 50 mol %, preferably 32 mol % or less from the viewpoint of oxygen barrier properties. Although the lower limit of the ethylene content is not specified, it is preferably 25 mol % or more because the flexibility of the EVOH layer 12a tends to decrease as the ethylene content decreases. Also, the EVOH layer 12a preferably contains an oxygen absorber. By including an oxygen absorber in the EVOH layer 12a, the oxygen barrier properties of the EVOH layer 12a can be further improved.

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 holes 15 are preferably formed in the outer layer 11 using a heating type punching device. It prevents the hole from reaching the inner bag 13 during formation. From this point of view, the difference (melting point of EVOH)-(melting point of random copolymer layer) should be large, preferably 15° C. or higher, and particularly preferably 30° C. or higher. The difference in melting point is, for example, 5 to 50°C, specifically, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50°C. or within a range between the two.

The inner surface layer 12b is a layer that contacts the contents of the double container 1, and is made of polyolefin such as low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymer, and mixtures thereof. It is preferably composed of low density polyethylene or linear low density polyethylene. The tensile modulus of the resin forming the inner layer 12b is preferably 50 to 300 MPa, more preferably 70 to 200 MPa. This is because the inner surface layer 13b is particularly flexible when the tensile modulus is within such a range. Specifically, the tensile modulus is, specifically, for example, 50, 100, 150, 200, 250, 300 MPa, and may be within a range between any two of the numerical values exemplified here. .

The adhesive layer 12c is a layer having a function of adhering the EVOH layer 12a and the inner surface layer 12b. , ethylene vinyl acetate copolymer (EVA). An example of the adhesive layer 12c is a mixture of low density polyethylene or linear low density polyethylene and acid-modified polyethylene.

As shown in FIGS. 2 and 3, a recess 7a is formed in the outer layer 11 at the shoulder portion of the accommodating portion 3, and an air introduction hole 15 is formed in the recess 7a. The air introduction hole 15 is a through hole provided only in the outer layer 11 and does not reach the inner layer 12 . An intermediate space 21 is formed between the outer layer 11 and the inner layer 12, which are outer shells, by introducing air from the atmosphere introduction hole 15. As shown in FIG. That is, the intermediate space 21 and the external space are communicated with each other through the atmosphere introduction hole 15 .

A valve member 5 is provided in the atmosphere introduction hole 15. The valve member 5 is inserted through the outside air introduction hole 15 and is slidably movable relative to the outside air introduction hole 15, and an intermediate portion of the shaft portion 5a. The cover portion 5c is provided on the space 21 side and has a larger cross-sectional area than the shaft portion 5a, and the locking portion 5b is provided on the outer space S side of the shaft portion 5a and prevents the valve member 5 from entering the intermediate space 21. Prepare.

The lid portion 5c is configured to substantially close the outside air introduction hole 15 when the outer layer 11 is compressed, and has a cross-sectional area that decreases as it approaches the shaft portion 5a. Further, the engaging portion 5b is configured so that air can be introduced into the intermediate space 21 when the outer layer 11 is restored after being compressed. When the outer layer 11 is compressed, the pressure inside the intermediate space 21 becomes higher than the external pressure, and the air inside the intermediate space 21 leaks out from the outside air introduction hole 15 . Due to this pressure difference and the flow of air, the lid portion 5c moves toward the outside air introduction hole 15, and the lid portion 5c closes the outside air introduction hole 15. As shown in FIG. Since the lid portion 5c has a shape in which the cross-sectional area decreases as it approaches the shaft portion 5a, the lid portion 5c easily fits into the outside air introduction hole 15 and closes the outside air introduction hole 15. As shown in FIG.

When the outer layer 11 is further compressed in this state, the pressure in the intermediate space 21 increases, and as a result, the inner layer 12 is compressed and the contents in the inner layer 12 are discharged. Further, when the compressive force applied to the outer layer 11 is released, the outer layer 11 attempts to restore itself due to its own elasticity. At this time, the lid portion 5 c is separated from the outside air introduction hole 15 to release the blockage of the outside air introduction hole 15 , and the 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 that abuts on the outer layer 11. , a gap is provided between the outer layer 11 and the locking portion 5b. Instead of providing the projection 5d, a groove may be provided in the engaging portion 5b to prevent the engaging portion 5b from blocking the outside air introduction hole 15. FIG.

Next, the operation of using the double container 1 (double container) having a check valve will be described.

As shown in FIGS. 5(a) to 5(c), the side surface of the outer layer 11 is gripped and compressed while the product filled with the contents is tilted, and the contents are discharged. At the start of use, there is substantially no gap between the inner layer 12 and the outer layer 11, so the compressive force applied to the outer layer 11 becomes the compressive force of the inner layer 12 as it is, and the inner layer 12 is compressed and the contents are compressed. Dispensed.

The cap 30 incorporates a check valve so that the contents in the inner layer 12 can be discharged, but outside air does not flow back into the inner layer 12 . Therefore, when the compressive force applied to the outer layer 11 is removed after the content is discharged, the outer layer 11 attempts to return to its original shape by its own restoring force, but only the outer layer 11 expands while the inner layer 12 remains deflated. Become. Then, as shown in FIG. 5D, the inside of the intermediate space 21 between the inner layer 12 and the outer layer 11 is decompressed, and the outside air is introduced into the intermediate space 21 through the outside air introduction holes 15 formed in the outer layer 11. . When the intermediate space 21 is in a decompressed state, the valve member 5 is not pressed against the atmosphere introduction hole 15, so the introduction of outside air is not hindered.

Next, as shown in FIG. 5(e), when the side surface of the outer layer 11 is gripped and compressed again, the valve member 5 abuts against and closes the atmosphere introduction hole 15, thereby reducing the pressure in the intermediate space 21. The increased compressive force applied to the outer layer 11 is transmitted to the inner layer 12 via the intermediate space 21, and this force compresses the inner layer 12 to eject the contents. When the compressive force applied to the outer layer 11 after the contents are discharged is removed, as shown in FIG. restored to its original shape.

The structure of the container body 2 is as described above, and in the container body 2 , the end surfaces of the outer layer 11 and the inner layer 12 are exposed at the mouth portion 4 . If the end face of the outer layer 11 and the end face of the inner layer 12 are exposed, the inner layer 12 may be peeled off therefrom. Therefore, in the double container 1 of the present embodiment, a protective member is attached to the tip of the mouth portion 4 to prevent the peeling of the outer layer 11 and the inner layer 12 . The structure of the mouth portion 4 of the container body 2 and its vicinity will be described in detail below.

FIG. 6 shows the vicinity of the mouth portion 4 of the container body 2. In the container body 2 in which unnecessary portions are cut off after blow molding, as shown in FIG. A cut end surface 11d of the outer layer 11 and a cut end surface 12d of the inner layer 12 are exposed. If the end face 11d of the outer layer 11 and the end face 12d of the inner layer 12 are exposed in this manner, there is a possibility that the inner layer 12 may be peeled off from the exposed end face 11d.

In the double container 1 of this embodiment, the protective member 40 is attached so as to contact the exposed end surface 11d of the outer layer 11 and the exposed end surface 12d of the inner layer 12 to prevent the inner layer 12 from peeling off. The protective member 40 is, for example, an annular (ring-shaped) aluminum foil, and as shown in FIGS. It is mounted by being brought into contact with the end face 12d) of the inner layer 12 and welded. At the time of welding, it is preferable to provide a welding margin of about 1 mm with respect to the end portion of the inner layer 12 . By welding the protective member 40 , the outer layer 11 and the inner layer 12 are fixed through the protective member 40 , so that the inner layer 12 is prevented from being unintentionally peeled off.

FIG. 7 shows how the cap 30 is attached to the container body 2 to which the protective member 40 is attached (welded). The cap 30 is attached to the mouth portion 4 of the container body 2, and as shown in FIG. It is composed of a cap body 32 screwed to a screw portion 31a provided on the outer peripheral surface.

The fixed part 31 is attached to the mouth part 4 of the container body 2 by plugging, and a screw thread 31a is formed on the outer peripheral surface thereof.

The cap body 32 is composed of a check valve 33 and a lid portion 35 that covers the spout via a hinge 34 and the like, and has an inner ring 35 that contacts the inner peripheral surface of the spout portion 4 when attached. there is The check valve 33 is fitted in the inner ring 35 so as to open and close the pouring hole 38 provided in the valve seat portion 36 in the inner ring 35, and the outer peripheral portion is pressed by the pressing member 37 to be fixed. It is

By screwing the cap main body 32 to the fixing portion 31, the inner ring 35 of the cap main body 32 enters the mouth portion 4, and the outer peripheral surface thereof contacts the inner peripheral surface of the mouth portion 4, thereby forming a sealed state.

The effect of attaching the protective member 40 is remarkable in a pump-type double container. 8 and 9 show how the pump 50 is attached to the mouth portion 4 of the container body 2 on which the protective member 40 is mounted. The pump 50 is composed of a nozzle portion 51 for pressing operation, an attachment portion 52 to the container body 2, and a suction pipe 53 inserted into the container body 2. It is attached to the portion 4 by a screwing method and is attached via a packing 60 . By interposing the packing 60, airtightness is ensured.

In the case of a pump-type double container, the inner layer of the mouth part may be damaged by interference when inserting the filling nozzle or pump, especially the friction of the packing when screwing in the pump because it is a screw-in method, and the negative pressure inside the container when the pump is operating. Although there is a possibility that the outer layer 11 and the inner layer 12 are fixed by welding the protective member 40, the inner layer 12 will not be peeled off even if these forces are applied.

The shape of the protective member 40 is not limited to the ring-shaped one described above. For example, as shown in FIGS. aluminum foil). A disk-shaped protective member 40 is brought into contact with the tip of the mouth portion 4 (the end face 11d of the outer layer 11 and the end face 12d of the inner layer 12) and welded. In this case, as shown in FIGS. 9(B) and 9(C), the opening 4 of the container body 2 is sealed by the protective member 40, so that the central portion of the protective member 40 is closed at the start of use. Cleavage and unsealing are preferred. As a means for facilitating unsealing, a cross-shaped slit 41, a half cut, or the like may be provided at the central position of the disk-shaped protective member 40. FIG.

When the ring-shaped protective member 40 is used, as shown in FIGS. The peeling of the inner layer 12 may be suppressed by contacting the upper end portion of the surface. In this case, the ring-shaped protection member 40 may be attached by welding, or may be attached by press fitting, for example.

FIG. 12 shows a configuration in which a ring-shaped protective member 40 having ribs (sleeves) 42 is applied to a pump-type double container, and the pump-type double container has ribs (sleeves) 42. The peeling prevention effect of the ring-shaped protective member 40 functions effectively.

The protective member 40 described above is attached (welded) to the end surface 11d of the outer layer 11 and the end surface 12d of the inner layer 12 at the tip of the mouth portion 4. By increasing the diameter of the tip of the mouth portion 4, the contact area is increased. By doing so, the fixed state can be made stronger. For example, as shown in FIG. 13, when the tip of the mouth portion 4 is enlarged in diameter, the outer layer 11 and the inner layer 12 become oblique at the tip of the mouth portion 4, and the respective end faces 11d and 12d are cut obliquely with respect to the thickness direction. will be As a result, the dimensions of the end surfaces 11d and 12d exposed at the tip of the mouth portion 4 are enlarged, and in the case of welding, the welding area is enlarged and the fixing is more strongly carried out.

Alternatively, as shown in FIG. 14(A), in the vicinity of the mouth portion 4, a portion where the outer layer 11 and the inner layer 12 are horizontal is provided, and the tip is cut so as to stand up slightly. As shown in B), the tip portions of the outer layer 11 and the inner layer 12 may be crushed by welding, so that the protection member 40 and the inner layer 12 may come into surface contact with each other.

Although the embodiment to which the present invention is applied has been described above, the present invention is not limited to this embodiment, and it goes without saying that various modifications are possible without departing from the gist of the present invention. . For example, it is effective to apply the present invention not only to pump-type containers, but also to containers with screw-on caps, since frictional force may be applied by rotation, and the inner layer may separate from the outer layer.

1 Double container 2 Container main body 3 Storage part 4 Mouth part 5 Valve member 11 Outer layer 11d End surface 12 Inner layer 12d End surface 15 Outside air introduction hole 30 Cap 31 Fixing part 32 Cap main body 33 Check valve 34 Lid part 35 Inner ring 38 Spout hole 40 protective member 41 slit 42 rib (sleeve)

Claims (4)

A double container having an outer layer and an inner layer, wherein the inner layer shrinks as the content stored in the inner layer decreases,
end surfaces of the outer layer and the inner layer are exposed at the tip of the mouth,
The tip of the mouth portion is enlarged in diameter, the outer layer and the inner layer are inclined,
A protective member is attached to the tip of the mouth,
The protective member has a rib that is in contact with the inner peripheral surface of the inner layer at the tip of the mouth, and is press-fitted. is worn and
A pump or a cap is attached by screwing through a packing to the opening to which the protective member is attached. A double container characterized by: A double container having an outer layer and an inner layer, wherein the inner layer shrinks as the content stored in the inner layer decreases,
end surfaces of the outer layer and the inner layer are exposed at the tip of the mouth,
A protective member is attached to the tip of the mouth,
The protective member is an annular member, and has ais welded and
A pump or a cap is attached by screwing through a packing to the opening to which the protective member is attached. A double container characterized by: 3. The double container according to claim 2, wherein the protective member has a rib contacting the inner peripheral surface of the inner layer at the tip of the mouth portion. 4. The double container according to claim 3, wherein the tip of the mouth portion is enlarged in diameter, and the outer layer and the inner layer are inclined.

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