JP2002347821A - Gas-permeable packing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas-permeable packing that is effective to prevent a liquid or solid, in which a chemical change takes place so that a gas is produced, from rupturing its container, that prevents degradation of the liquid impermeability and gas-permeability of a porous film even if the container turns over and its porous film gets wet, and that prevents a leakage of the contents. SOLUTION: The water-impermeable, gas permeable, and porous film 2 formed from polyolefin having a limiting viscosity of 3 dl/g or larger is affixed to at least one side of packing base material 4 formed from polyolefin having a passage 3 defined therein. Thus, the permeable packing can allow passage of gases through it but can prevent a leakage of liquid or solid contents.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a breathable packing suitable for a container cap. In particular, the present invention preferably relates to a breathable packing suitable for a cap of a container filled with contents in which gas is easily generated.

[0002]

2. Description of the Related Art Conventionally, this kind of breathable packing includes:
A liquid-permeable, air-permeable film-shaped material is used. As such a film-like material, a porous film made of tetrafluoroethylene or a polyolefin film-like material of a woven or non-woven sheet whose molecular weight is not as high as the left has been used.

[0003]

However, the gas-permeable packing using the above-mentioned tetrafluoroethylene or a polyolefin film having a molecular weight not so high as the left is not suitable for a gas-generating liquid container. Although the container escapes, there is a problem that the contents (liquid) leak after a lapse of time after the container has fallen or turned over and the entire surface of the gas permeable packing has been covered (wetted) with liquid.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to effectively prevent the rupture of a container containing a liquid or a solid which generates gas, and furthermore, the container may be overturned. It is an object of the present invention to provide a gas-permeable packing in which the liquid-permeability and the gas permeability are not impaired for a long period of time even when wet with liquid contents, and the contents do not leak.

[0005]

In order to achieve the above-mentioned object, the breathable packing according to the present invention has an intrinsic viscosity [η].
Is characterized in that a polyolefin packing substrate having a gas passage is laminated on at least one surface of a microporous polyolefin film of 3 dl / g or more. When used for packing, the gas generated was allowed to escape, but the liquid or solid was not leaked.

[0006] In the breathable packing according to the second aspect of the present invention, the microporous polyolefin film may be:
Porosity 25-90%, Air permeability 50-2000 sec / 100
cc and a thickness in the range of 10 to 200 μm, in the breathable packing according to the invention of claim 3, wherein the polyolefin microporous film has an average pore size of 0.001 to 0.001.
The range of 2.0 μm is for keeping the air permeability and the liquid impermeability (liquid blocking property) higher.
Furthermore, the reason why the breathable packing according to the invention of claim 4 is that the polyolefin microporous film is biaxially oriented is to increase mechanical strength such as piercing strength. .

[0007] Furthermore, in the breathable packing according to the invention of claim 5, the polyolefin packing base material is laminated at least on a portion in contact with a peripheral portion of a container mouth. The polyolefin packing base material of the breathable packing according to the invention is a foam, and the polyolefin packing base material of the breathable packing according to the invention of claim 7, wherein the expansion ratio is 1.1 to 5 times, The closed cell foam having a thickness in the range of 0.5 to 3 mm is used so that a more suitable packing effect (sealing effect) can be obtained. In the breathable packing according to the invention of claim 8, the gas passage of the polyolefin packing substrate has 1 to 20 holes / c having an average hole diameter of 0.1 to 2 mm.
The reason why the gas is retained in the range of m2 is to be able to cope with the amount of gas generated from the contents when the cap is closed in the container.

Further, in the breathable packing according to the invention of claim 9, the polyolefin as a material of the polyolefin microporous film and the polyolefin packing substrate is an ethylene polymer, a propylene polymer or a mixture thereof. The reason is that heat resistance, mechanical strength, water resistance, chemical resistance and the like are excellently balanced, and a fine-grained seal composed of fine and uniform closed cells can be obtained.

The polyolefin microporous film (hereinafter sometimes referred to as "microporous film") has an intrinsic viscosity [η] of 3 dl / g or more because of its excellent mechanical strength such as piercing strength. That's why. Further, in order to exhibit the performance of releasing gas generated from the contents by laminating with a polyolefin packing base material described below (hereinafter sometimes referred to as “packing base material”), liquid or solid is not leaked. is there. The upper limit of the intrinsic viscosity [η] is
Although not particularly limited, if it is too high, the melt viscosity becomes high, and it becomes difficult to form a film, so that a microporous film having a good appearance may not be obtained. Therefore, usually, 25 dl / g or less is preferable. On the other hand, a microporous film having an intrinsic viscosity [η] of less than 3 dl / g tends to have poor mechanical strength, and there is a possibility that a packing having good performance cannot be obtained. Practically, 4 dl / g or more is preferable.

The microporous film has a porosity of 25 to 90.
% (Preferably 30 to 80%), air permeability 50 to 200
0 sec / 100 cc (preferably 70 to 1500 sec / 1
00 cc) and a thickness of 10 to 200 μm (preferably 15
１００100 μm). Further, the average pore size is 0.001 to 2.0 μm (preferably 0.01 to 1.
5 μm) is preferable.

The microporous film has a porosity of 25.
%, An air permeability of more than 2000 sec / 100 cc, and an air hole having an average pore diameter of less than 0.001 μm may have poor air permeability. On the other hand, those having a porosity of more than 90%, those having an air permeability of less than 50 seconds / 100 cc, and those having an average pore diameter of more than 2.0 μm may be inferior in liquid impermeability. Of course, when the porosity, air permeability, and average pore diameter satisfy the above, packing excellent in balance between air permeability and liquid impermeability can be obtained. When a biaxially oriented film is used as the microporous film, mechanical strength such as piercing strength becomes more excellent.

The intrinsic viscosity [η] is a value measured at 135 ° C. in a decalin solvent. The measurement method is ASTM D
4020. The thickness of the microporous film was measured using a film thickness meter (Miniax DH-150 type, manufactured by Tokyo Seimitsu Co., Ltd.). The average pore size is
The maximum value of the pore diameter measured by a mercury porosimeter (Autoscan 33 <manufactured by Yuasa Ionics>) was used.

The porosity is determined by measuring the weight of the film, setting the density to 0.95 g / cm 3, and calculating the thickness of the dense film by calculation. I asked. Porosity (volume%) = [(T0
−TW) / T0] × 100 where T0 is the actual film thickness obtained by a film thickness measuring instrument, and TW is the film thickness assuming a porosity of 0% calculated from the weight.

The air permeability can be measured by AS using a standard Gurley densometer (manufactured by Toyo Seiki Seisaku-sho, Ltd.).
It was measured according to TM D726.

The polyolefin as a raw material of the microporous film includes ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene,
A homo- or copolymer of an α-olefin having 2 to 10 carbon atoms such as decene. This raw material may be a single polyolefin or a mixture of two or more polyolefins having different intrinsic viscosities [η]. In the case of the mixture, a polyolefin having an intrinsic viscosity [η] of less than 3 dl / g may be contained, but it is necessary to satisfy 3 dl / g or more as a whole.

Among the above-mentioned polyolefins, a propylene homopolymer or propylene and 5% by weight or less of α-
A propylene polymer which is a copolymer with an olefin and a homopolymer of ethylene or an ethylene polymer which is a copolymer of ethylene and 5% by weight or less of α-olefin are preferred. Above all, when an ethylene polymer is used for laminating a microporous film and a polyolefin packing substrate, it is particularly preferable because it is easy to heat seal and can be used for heat sterilization.

The method for producing the microporous film is not particularly limited. For example, a previously obtained biaxially oriented polyolefin film having an intrinsic viscosity [η] of 3 dl / g or more is heat-treated under specific conditions. A polyolefin having an intrinsic viscosity [η] of 3 dl / g or more, for example, n-alkane such as n-decane, n-dodecane, docosane, trichosane, tetracosane, etc., liquid paraffin, kerosene,
Aliphatic or cyclic hydrocarbon compounds such as paraffin wax, naphthalene, tetralin, diethylbenzene,
Aromatic hydrocarbon compounds such as decalin or hydrogenated derivatives thereof, higher fatty acids such as stearic acid, higher aliphatic alcohols such as stearyl alcohol, higher fatty acid amides such as stearamide, dioctyl phthalate, di-n-phthalate Non-volatile organic low-molecular-weight compounds such as phthalic acid esters such as butyl, or finely divided silica, calcium silicate, calcium carbonate, and finely divided inorganic powder such as talc are added to obtain a sheet. A method is conceivable in which any of the steps before, during, or after the biaxial stretching or a combination of several steps is used to remove the organic low-molecular-weight compound or the inorganic fine powder. Of course, it does not limit the gain in other ways.

More specific methods for producing the microporous film are described in JP-A-10-258462 and JP-A-10-258462.
No. 306168, Japanese Patent No. 271633, Japanese Patent Laid-Open No. 5-234578, Japanese Patent Laid-Open No. 6-212006
And JP-A-60-255107.

As the packing substrate, any film or sheet having cushioning properties can be used, but preferably a foam comprising an open-cell foam or a closed-cell foam is selected. In the case of an open-cell foam, a gas passage is provided by itself, but since a closed-cell foam has no air permeability, it is necessary to positively form a gas passage.

The gas passage may have any hole diameter as long as the gas can pass through the passage. For example, when the amount of gas generated from the contents is small, that is, for packing of a container in which the internal pressure does not increase to the left, at least a portion contacting the peripheral portion of the container mouth portion is laminated with a polyolefin packing base material, and the center portion is It is only necessary to form a gas passage of 2 to 10 mm. Further, for packing a container that generates a large amount of gas and has a high internal pressure, it is usually preferable to set the gas passage in a range of 1 to 20 holes / cm2 having an average hole diameter of 0.1 to 2 mm. The method of forming the hole for the gas passage is not particularly limited, but includes, for example, a needle punch method.

The foam used as the packing substrate has an expansion ratio of 1.1 to 5 times (preferably 2 to 3 times),
A closed-cell foam having a thickness in the range of 0.5 to 3 mm (preferably, 1 to 2 mm) is preferable because it is excellent in restorability, sealability, and the like.

The polyolefin as a raw material of the packing base material is ethylene, propylene, 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene,
A homo- or copolymer of an α-olefin having 2 to 10 carbon atoms such as decene, usually a high-pressure low-density polyethylene, a linear low-density polyethylene, a medium-density polyethylene, a high-density polyethylene, a polypropylene, poly 1-butene ,
It is a low-crystalline or amorphous polyolefin such as a crystalline polyolefin known as poly-4-methyl-1-pentene or the like, an ethylene / α-olefin random copolymer, and a propylene / α-olefin random copolymer. These polyolefins may be used alone or as a mixture of two or more polyolefins. Among them, ethylene polymers such as high-pressure low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, and high-density polyethylene; homopolymers of propylene; A propylene polymer, which is a so-called polypropylene, is preferred because a fine-grained foam having fine and uniform closed cells can be obtained.

The molecular weight of the polyolefin as a raw material of the packing base material is not particularly limited as long as it has a molecular weight that can be molded into a foam, but generally, if it is an ethylene polymer, ASTM D1238 (190 ° C.) C,
The melt flow rate (MFR) measured according to a load of 2,160 g) is 0.1 to 50 g / min (preferably 2 to 50 g / min).
10 g / min). In the case of a propylene polymer, ASTM D1238 (230 ° C, load 2,
160g) and the melt flow rate (MF
R) is 0.1 to 50 g / min (preferably 0.1 to 10 g / min).
g / min) are advantageously used.

[0024]

Next, embodiments of the present invention will be described with reference to the accompanying drawings. 1 is a schematic enlarged cross-sectional view of the packing of the present application, FIG. 2 is a schematic cross-sectional view when applied to a cap of a container (bottle), and FIG. 3 is a test piece of an example and a comparative example, and the test piece is applied. FIG. 4 shows a container with a closed cap and a gas permeation test method, and FIG.
It is a figure showing a result (table) of a liquid leak test.

As shown in FIG. 1, the packing 1 of the present application includes a gas passage 3 on one side of a liquid-permeable, air-permeable microporous film 2.
Are laminated on each other. Of course, a packing substrate 4 having gas passages 3 on both surfaces of the microporous film 2 may be laminated. Alternatively, the microporous film 2 may be laminated on both sides of the packing substrate 4 having the gas passage 3 as a center.

As shown in FIG. 2 (a), the packing 1 of the present invention is loaded so that the microporous film 2 side faces the inner top surface of a screw cap 6 which can be screwed into the mouth of a container (bottle) 5. You. The packing 1 of the present application is punched in advance in accordance with the inner diameter of the cap 6. For this punching, it is preferable to make the diameter slightly larger than the inner diameter of the cap.

The container 5 contains contents (eg, hypochlorous acid aqueous solution, hydrogen peroxide solution, fermentable contents, fragrance, etc.).
The container 5 is filled with a cap 6, and the mouth of the container 5 is covered with a cap 6 loaded with the packing 1 of the present invention, and is attached with a constant closing torque.

A gas is generated from the contents 7 with the passage of time. The gas (arrow G) passes through the microporous film 2 of the packing 1 of the present invention, passes through the air passage 3 of the packing base material 4, and caps. 6 and is released into the atmosphere from the periphery of the cap 6 through the screw portion 6 '. Therefore, it is possible to avoid a high pressure in the container 5 due to the gas generated from the contents 7, which is effective for preventing the container from bursting.

In the packing 1 of the present invention, the container 5 filled with the contents 7 which is a liquid in which gas is liable to be generated is formed as shown in FIG.
As shown in (b), when the liquid as a content is in contact with the packing 1 of the present application in the cap 6 and is completely wetted, the liquid-permeability of the microporous film 2 is long even when the liquid has fallen over (side down). It is secured over time and has the effect of not leaking liquid.

[0030]

Example 1 Intrinsic viscosity [η] is 5 dl / g and porosity is 63
%, Thickness 35 μm having air permeability of 170 s / 100 cc
Packing substrate made of polyethylene closed cell foam with a foaming ratio of 2x and a thickness of 1.5mm with a hole 3 having a diameter of 10mm formed on one side of a liquid-permeable, gas-permeable microporous film 2 made of polyethylene 4 at 110 ° C for 10 seconds
Then, as shown in FIG. 3 (a), this was punched out into a disk having a diameter of 22.7 mm with the hole 3 as a center to obtain a packing 1 of the present invention.

The size of the packing 1 of the present invention is the same as that of the polypropylene screw cap 6 having an inner diameter of 22 mm which can be screwed into the mouth of an empty 100 cc polyethylene terephthalate bottle (container) 5 shown in FIG. This is because the microporous film 2 is tightly loaded on the top surface such that the microporous film 2 faces inward. The cap 6 has a hole 3 'having a diameter of 5 mm at the center of the top surface.

100 cc of a 12% aqueous solution of sodium hypochlorite is placed in the bottle (container) 5, the cap 6 in which the packing 1 of the present invention is loaded as described above is closed, and a torque of 20 k is applied.
g · cm, and immersed in water of a transparent container 8 filled with water and fixed with a fixture 9 as shown in FIG.
The upper layer air is sucked through a suction pipe 10 by a vacuum pump (not shown), and it is determined whether or not the air bubbles K retained in the bottle (vessel) 5 come out of the hole 3 ′ at the center of the cap 6. When the gas permeation test was performed, the result of FIG. 4 was obtained.

Further, 100 cc of a 12% aqueous solution of sodium hypochlorite is placed in the bottle (container) 5 in the same manner as described above, and the cap 6 in which the packing 1 of the present invention is loaded as described above.
And close it down with the torque of 20 kgcm,
After leaving at 35 ° C. for one week, a liquid leakage test was performed based on whether or not the aqueous solution leaked from the hole at the center of the cap 6, and the result shown in FIG. 4 was obtained.

[0034]

Example 2 The same conditions and method as in Example 1 were used except that the polyethylene packing base material 4 had four needle holes 3 per cm 2 as shown in FIG. A gas permeation test and a liquid leakage test were performed to obtain the results shown in FIG.

[0035]

Example 3 The same conditions as in Example 1 were used except that a packing base material 4 made of polypropylene was used, and the cap 6 loaded with the packing 1 of the present invention was mounted on a container with a closing torque of 30 kg · cm. When the gas permeation test and the liquid leakage test were performed by the method, the results shown in FIG. 4 were obtained.

[0036]

Comparative Example 1 The porous film 3 was made into a tetrafluoroethylene film (Zytex A-150 <manufactured by Norton Co., Ltd.).
A gas permeation test and a liquid leakage test were performed under the same conditions and method as in Example 1 except that heat fusion was performed for 15 seconds, and the results in FIG. 4 were obtained.

[0037]

COMPARATIVE EXAMPLE 2 The porous film 3 was made into a tetrafluoroethylene film (Zytex G-110 <manufactured by Norton Co., Ltd.), and the packing substrate 2 was heated at 130 ° C.
A gas permeation test and a liquid leakage test were performed under the same conditions and method as in Example 1 except that heat fusion was performed for 15 seconds, and the results in FIG. 4 were obtained.

[0038]

Comparative Example 3 The porous film 3 was made into Tyvek <manufactured by DuPont>, a nonwoven fabric made of hot-melt-coated polyethylene.
A gas permeation test and a liquid leakage test were performed under the same conditions and method as in Example 1 except that heat fusion was performed for 15 seconds, and the results in FIG. 4 were obtained.

As a result, gas permeation is obtained in Examples 1 to 3. Further, in the liquid leakage test, there was no liquid leakage even after one week at 35 ° C. On the other hand, in Comparative Examples 1 to 3, gas permeation was recognized, but in the liquid leakage test, all liquid leakage occurred after one week at 35 ° C. From this, it was confirmed that Examples 1 to 3 using the packing of the present application were superior to those of Comparative Examples 1 to 3.

[0040]

As described above, according to the present invention, a polyolefin packing base material having a gas passage is laminated on at least one surface of a polyolefin microporous film having an intrinsic viscosity [η] of 3 dl / g or more. Gas is released when used as a packing for caps of containers containing liquids or solids that generate gas, but does not leak liquid or solid contents even if it falls down. This is an excellent effect.

According to a second aspect of the present invention, the polyolefin microporous film has a porosity of 25 to 90%, an air permeability of 50 to 2000 seconds / 100 cc, and a thickness of 10 to 20.
Since it is characterized by being in the range of 0 μm, it has an excellent effect that the performance of gas permeability and liquid-permeability (liquid blocking property) can be kept higher.

Further, the invention according to claim 3 is characterized in that the microporous polyolefin film has an average pore size of 0.001 to 0.001.
Since it is characterized by being in the range of 2.0 μm, the performance of air permeability and liquid impermeability (liquid blocking property) can be kept higher, and the hole diameter of this microporous film is
When the thickness is 0.1 μm or less, it is also used for food and has an excellent effect of preventing the invasion of bacteria.

Further, the invention according to claim 4 is characterized in that the polyolefin microporous film is biaxially oriented, so that the mechanical strength such as piercing strength is further improved. It is effective.

Furthermore, the invention according to claim 5 is characterized in that the polyolefin packing base material is laminated at least on a portion that comes into contact with the peripheral edge of the container mouth, so that the container and the cap are in close contact with each other. This is an excellent effect that the packing effect (sealing effect) in the portion can be obtained in a more suitable state.

Further, the invention according to claim 6 is characterized in that the polyolefin packing base material is a foam, so that the packing effect (sealing effect) at the close contact portion between the container and the cap is more favorable. It has an excellent effect of being obtained in a state.

Further, the invention according to claim 7 is characterized in that the polyolefin packing base material has an expansion ratio of 1.1 to 5.
It is characterized by being a closed cell foam having a thickness of 0.5 to 3 mm in thickness, so that when the cap is closed in the container, the necessary packing effect (sealing effect) becomes more suitable. It has an excellent effect that it can be obtained.

Further, the invention according to claim 8 is characterized in that the gas passage of the polyolefin packing substrate has:
Since holes having an average hole diameter of 0.1 to 2 mm are held in a range of 1 to 20 holes / cm 2, the amount of gas generated from the contents when the cap is closed in the container can be handled. This is an excellent effect.

Further, the invention according to claim 9 is characterized in that the polyolefin which is a material of the polyolefin microporous film and the polyolefin packing substrate is an ethylene polymer, a propylene polymer or a mixture thereof. Therefore, the present invention has an excellent effect of being excellent in the balance among heat resistance, mechanical strength, water resistance, chemical resistance and the like, and obtaining fine sealing properties including fine and uniform closed cells.

[Brief description of the drawings]

FIG. 1 is a schematic enlarged sectional view of a packing of the present application.

FIGS. 2A and 2B are schematic cross-sectional views when applied to a cap of a container (bottle), wherein FIG.

FIGS. 3A and 3B are test pieces of Examples and Comparative Examples,
(C) is a container in which the cap to which the test piece is applied is closed,
(D) is a figure which shows each gas permeation test method.

FIG. 4 is a diagram showing the results (table) of a gas permeation test and a liquid leakage test.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Packing of this application 2 Porous film 3 Gas passage 3 'Cap hole 4 Packing base material 5 Container (bottle) 6 Cap 6' Screw part 7 Contents 8 Transparent container 9 Fixture 10 Suction pipe K Air bubble

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] August 14, 2002 (2002.8.1
4)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

3. The microporous polyolefin film according to claim 1,
Porosity 25-90%, Air permeability 50-2000 sec / 100
The breathable packing according to claim 1 or 2 , wherein the cc and the thickness are in the range of 10 to 200 µm.

Wherein said microporous polyolefin film,
The breathable packing according to any one of claims 1 to 3, wherein the average pore diameter is in a range of 0.001 to 2.0 µm.

Wherein said microporous polyolefin film,
Claim 1-4, characterized in that is obtained by biaxially oriented
A breathable packing according to any one of the preceding claims.

Wherein said polyolefin packing substrate,
The air-permeable packing according to any one of claims 1 to 5 , wherein the air-permeable packing is laminated at least on a portion that comes into contact with a peripheral edge of the container mouth.

7. The polyolefin packing substrate,
The breathable packing according to any one of claims 1 to 6 , comprising an open-cell foam or a closed-cell foam .

Wherein said polyolefin packing substrate,
Claim 1-7, characterized in that the expansion ratio 1.1 to 5 times, closed cell foam in the range of thickness 0.5~3mm
A breathable packing according to any one of the preceding claims.

Passage 9. The gas with the said polyolefin packing substrate, a hole having an average diameter 0.1 to 2 mm 1 to 2
The breathable packing according to any one of claims 1 to 8 , wherein the packing is held in a range of 0 pieces / cm2.

10. Polyolefin is a material of the polyolefin microporous film and the polyolefin packing substrate, ethylene polymers, one of the claims 1-9, characterized in that a propylene polymer or a mixture thereof The described breathable packing.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction contents]

[0006] The breathable packing according to the second aspect of the present invention is characterized in that the polyolefin microporous film is
Centering on the polyolefin packing substrate,
It is characterized by being laminated on the surface, centering on the base material
Both sides are of the same nature (for example, escape gas
But not leak liquid or solid).
Was. The breathable packing according to the invention of claim 3 is :
The polyolefin microporous film has a porosity of 25 to 9;
0%, air permeability 50-2000 sec / 100cc and thickness 1
In the range of 0～200Myuemu, breathable packing according to the invention of claim 4, wherein the polyolefin microporous film, the range of the average pore diameter 0.001~2.0μm
Since it is, respectively configured as higher coercive performance of breathability and HiTorueki property (liquid barrier properties). further,
Breathable packing according to the invention of claim 5, wherein the polyolefin microporous film, a higher order of mechanical strength such as strength piercing by Rukoto using <br/> those biaxially oriented
It was configured to be.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

[0007] Furthermore, breathable packing according to the invention of claim 6, said polyolefin packing base material is laminated to the portion abutting against the peripheral portion of at least the container opening, according to claim 7 In the breathable packing according to the invention, the polyolefin packing base material is continuous.
9. The gas-permeable packing according to claim 8 , wherein the polyolefin packing base material is made of an open- cell foam or a closed-cell foam.
Times, closed cell foam in the range of thickness 0.5~3mm
By some, configured as suitable packing effect respectively (sealing effect) is obtained. Further, breathability packing according to the invention of claim 9, the passage of the gas with the said polyolefin packing base material has an average hole diameter 0.
By holding 1 to 2 mm holes in the range of 1 to 20 holes / cm 2, it is configured to be able to cope with the amount of gas generated from the contents when the cap is closed in the container.
Was .

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

[0008] Furthermore, breathable packing according to the invention of claim 10, polyolefin wherein a material of the polyolefin microporous film and the polyolefin packing base material is the ethylene polymer, propylene polymer, or a mixture thereof Thereby, the heat resistance, the mechanical strength, the water resistance, the chemical resistance, and the like are excellently balanced, and a fine-grained uniform closed cell composed of closed cells is obtained .

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0041

[Correction method] Change

[Correction contents]

Further, the invention according to claim 2, wherein the poly
The olefin microporous film is
Laminated on both sides centering on the king substrate
Feature, so that both sides of the
Properties (e.g., evolving gas, but not liquid or
(Solids do not leak). Further
The invention according to claim 3 is characterized in that the polyolefin microporous film has a porosity of 25 to 90% and an air permeability of 50 to 20.
Since it is characterized by being in the range of 00 sec / 100 cc and a thickness of 10 to 200 μm, it has an excellent effect that the performance of gas permeability and liquid impermeability (liquid blocking property) can be kept higher. is there.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0042

[Correction method] Change

[Correction contents]

Further, the invention according to claim 4 is characterized in that the microporous polyolefin film has an average pore diameter of 0.001 to 0.001.
Since it is characterized by being in the range of 2.0 μm, the performance of air permeability and liquid impermeability (liquid blocking property) can be kept higher, and the hole diameter of this microporous film is
When the thickness is 0.1 μm or less, it is also used for food and has an excellent effect of preventing the invasion of bacteria.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0043

[Correction method] Change

[Correction contents]

[0043] Furthermore, the invention according to claim 5, wherein the polyolefin microporous film, since it is characterized in that is obtained by biaxial orientation, excellent that the mechanical strength such as puncture strength is higher It has the effect that it has.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0044

[Correction method] Change

[Correction contents]

[0044] Furthermore, the invention according to claim 6, wherein the polyolefin packing substrate, because characterized in that it is laminated to the portion abutting against the peripheral portion of at least the container opening, the container and cap This is an excellent effect that the packing effect (sealing effect) in the close contact portion can be obtained in a more suitable state.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0045

[Correction method] Change

[Correction contents]

Furthermore, the invention according to claim 7 is characterized in that the polyolefin packing substrate is made of an open-cell foam.
Alternatively, since it is characterized by being a closed-cell foam, it has an excellent effect that a packing effect (sealing effect) can be obtained in a more suitable state at a close contact portion between the container and the cap.

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0046

[Correction method] Change

[Correction contents]

Further, the invention according to claim 8 is characterized in that the polyolefin packing substrate has an expansion ratio of 1.1 to 5
It is characterized by being a closed cell foam having a thickness of 0.5 to 3 mm in thickness, so that when the cap is closed in the container, the necessary packing effect (sealing effect) becomes more suitable. It has an excellent effect that it can be obtained.

[Procedure amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0047

[Correction method] Change

[Correction contents]

Further, according to the ninth aspect of the present invention, the gas passage of the polyolefin packing base material may include:
Since holes having an average hole diameter of 0.1 to 2 mm are held in a range of 1 to 20 holes / cm 2, the amount of gas generated from the contents when the cap is closed in the container can be handled. This is an excellent effect.

[Procedure amendment 12]

[Document name to be amended] Statement

[Correction target item name] 0048

[Correction method] Change

[Correction contents]

Further, the invention according to claim 10 is as follows:
Since the polyolefin, which is a material of the polyolefin microporous film and the polyolefin packing substrate, is characterized by being an ethylene polymer, a propylene polymer or a mixture thereof, heat resistance, mechanical strength, water resistance, and chemical resistance It is an excellent effect that the composition is excellent in balance and the like, and a fine-grained sealing property composed of fine and uniform closed cells can be obtained.

Continued on the front page F-term (reference) 3E084 AA04 AA12 AA24 AB05 BA01 CA01 DA01 DB12 FA09 FB01 GA04 GB04 HA01 HB03 HC07 HD01 4F100 AK03A AK03B AK04A AK04B AK07A AK07B AL05A AL05B BA02 BA03 DJ06 GB10 DJB GBA JB07 JD02A JD02B JD05 JJ03 JK01 YY00A YY00B

Claims (9)

[Claims] 1. A breathable packing comprising a polyolefin microporous film having an intrinsic viscosity [η] of 3 dl / g or more laminated with a polyolefin packing substrate having a gas passage on at least one surface. 2. The polyolefin microporous film,
Porosity 25-90%, Air permeability 50-2000 sec / 100
The breathable packing according to claim 1, characterized in that it has a cc and a thickness in the range of 10 to 200 µm. 3. The polyolefin microporous film,
The gas-permeable packing according to claim 1 or 2, wherein the average pore diameter is in a range of 0.001 to 2.0 µm. 4. The polyolefin microporous film,
4. It is biaxially oriented.
A breathable packing according to any one of the preceding claims. 5. The polyolefin packing substrate,
The gas-permeable packing according to any one of claims 1 to 4, wherein the gas-permeable packing is laminated at least on a portion that comes into contact with a peripheral portion of the container mouth. 6. The polyolefin packing substrate,
A foam according to any one of claims 1 to 5,
A breathable packing as described in. 7. The polyolefin packing substrate,
7. A closed-cell foam having an expansion ratio of 1.1 to 5 times and a thickness of 0.5 to 3 mm.
A breathable packing according to any one of the preceding claims. 8. The gas passage of the polyolefin packing substrate has a hole having an average hole diameter of 0.1 to 2 mm.
The breathable packing according to any one of claims 1 to 7, wherein the packing is held in a range of 0 pieces / cm2. 9. The method according to claim 1, wherein the polyolefin as a material of the microporous polyolefin film and the polyolefin packing substrate is an ethylene polymer, a propylene polymer or a mixture thereof. The described breathable packing.