JP5275299B2 - Gas permeable laminated plastic film and manufacturing apparatus thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated plastic film having an enough strength, excellent in gas permeability and easily unsealing properties, and having good appearance, and an apparatus for manufacturing it. <P>SOLUTION: The gas permeable laminated plastic film 1 consists of a base film layer 1a and a sealant layer 1b, and in this gas permeable laminated plastic film 1, a first micro-porous hole group 2 formed in the sealant layer 1b side covers the whole face of the sealant layer 1b and has a depth comparable as that of the sealant layer 1b, and a second micro-porous hole group 3 formed on the base film layer 1a side partly and covers the base film layer 1a in a strip from and has a depth comparable as that of the base film layer 1a, and in regions where the first and second micro-porous hole groups 2, 3 overlap, the micro-porous holes penetrate through the laminated plastic film 1, and thereby, the gas permeability is provided. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a laminated plastic film suitable for use in a lid of a container for fermented foods and the like, and an apparatus for producing the same, because it has sufficient strength, is excellent in gas permeability and easy opening, and has a good appearance.

  Fermented foods such as kimchi and natto are allowed to proceed with fermentation during storage and release carbon dioxide, so that the container lid is not completely sealed and is required to have gas permeability. In addition, since easy opening is indispensable, it is necessary to have a sealant layer having easy opening. Since the sealant layer cannot function as a lid unless the sealant layer is thick to some extent, for example, a layer in which a sealant layer having a thickness of about 45 μm is laminated on the base film layer is used.

As a technology for imparting gas permeability to a plastic film, Japanese Patent Publication No. 7-90568 (Patent Document 1) has a first roll and a surface on which a large number of particles having a Mohs hardness of 5 or more having sharp corners are attached. By passing the long film between the smooth rolls and adjusting the pressing force to the long film uniformly throughout the film, 500 through holes having a diameter of 50 μm or less are formed in the long film. A method of forming at a density of cm ² or more is disclosed. Japanese Patent Laid-Open No. 2002-59487 (Patent Document 2) discloses a first roll in which a large number of particles having a Mohs hardness of 5 or more having sharp corners are attached to the surface, and a plurality of rolls provided at intervals in the axial direction. A second roll having a large-diameter portion is disposed opposite to one another, one roll is fixed, and the other roll is movable so as to press against one roll with a desired pressure. The apparatus which forms a some strip | belt-shaped fine hole row | line | column in one surface of a long film is disclosed by allowing a long film to pass between both rolls.

  The apparatus of Patent Document 1 forms micropores on one entire surface of a long film, and the apparatus of Patent Document 2 forms a plurality of strip-shaped microhole arrays on one surface of a long film. When it becomes meat, the through-holes must be enlarged, so that there is a problem that sufficient film strength cannot be secured. In addition, when the through-hole is enlarged, the appearance of the film is deteriorated and becomes unsuitable for use as a container lid for printing.

Japanese Patent Publication No. 7-90568 JP 2002-59487 A

  Accordingly, an object of the present invention is to provide a laminated plastic film suitable for use in a lid of a container such as a fermented food because it has sufficient strength, has excellent gas permeability and easy opening, and has a good appearance, and its production Is to provide a device.

  As a result of earnest research in view of the above object, the present inventors, in the laminated plastic film consisting of the base film layer and the sealant layer, formed a micropore substantially penetrating only the sealant layer on the entire sealant layer side, It is excellent when a micropore penetrating only the base film layer on the base film layer side is formed in a strip shape at a predetermined interval, and the micropores on both sides are communicated with each other in the strip region. It was discovered that a gas-permeable easy-open laminated plastic film having sufficient strength and good appearance while having gas permeability was obtained, and the present invention was conceived.

That is, the gas permeable laminated plastic film of the present invention comprises a laminated plastic film of a base film layer having a thickness of 12 to 25 μm and a sealant layer having a thickness of 30 to 50 μm, and the sealant layer and the base film The sealant layer formed from both sides of the laminated plastic film by a perforating roll having a thickness ratio with the layer in a range of 1.5 / 1 to 5/1 and having a number of hard particles having sharp corners attached to the surface A first microhole group on the side and a second microhole group on the base film layer side, and the first microhole group covers the entire surface of the sealant layer and has the same depth as the sealant layer. has the second fine Anagun has the base film layer and the same degree of depth covers a strip of the base film layer partially, said first and second fine hole groups overlap In this region, both micropores communicate with each other to penetrate the laminated plastic film, thereby imparting gas permeability.

  The apparatus of the present invention for producing the gas permeable laminated plastic film has first and second punching devices arranged along the moving direction of the laminated plastic film, and (a) the first punching device. Is a first perforated roll disposed on the sealant layer side, and a first perforated roll disposed at a position facing the first perforated roll, with a number of hard particles having sharp corners attached to the surface. (B) the second perforating apparatus has a second surface smoothing roll rotating at a fixed position on the sealant layer side, and a large number of hard particles having sharp corners on the surface. A plurality of second perforating rolls that are attached and arranged along the axial direction so as to face the second surface smoothing roll, and the laminated plastic film comprises the first perforating roll When passing through the gap between the first surface smoothing roll and the gap between the second perforating roll and the second surface smoothing roll, the first micropore group is formed on the entire surface of the sealant layer. A plurality of second fine hole groups are partially formed in a band shape in the base film layer.

  In the above apparatus, the second perforating roll is movable with respect to the second smooth surface roll, so that the width and number of the second microhole group, and the micropores in the second microhole group, It is preferable that the area ratio and depth can be adjusted.

  In the above apparatus, the apparatus for driving the second perforated roll includes a table movable in the axial direction of the second surface smoothing roll and a direction of the second surface smoothing roll along the guide of the table. A movable carrier, and a holder that is supported by the carrier and rotatably supports the second piercing roll, the holder having means for detecting a load applied to the second piercing roll; It is preferable to adjust the area ratio and depth of the fine holes in the second fine hole group by controlling the distance between the second perforated roll and the second smooth surface roll in accordance with the load. .

  The gas permeable laminated plastic film of the present invention has micropores having the same depth as the whole on the sealant layer side, and is partially band-like with micropores having the same depth as the base film layer side. Therefore, a through hole is formed in a region where the fine holes on both sides communicate with each other. Therefore, (a) even if it is thick, through-holes can be obtained without enlarging the micropores on the base film layer side, so that sufficient gas permeability can be imparted to the laminated plastic film without reducing the strength. (B) It is possible to adjust the gas permeability of the laminated plastic film by adjusting the area ratio and depth of the fine holes formed in a band shape on the base film layer side, and the width and number of the fine band holes. (C) Since the micropores provided in the base film layer on the outside when used as a container lid are relatively small, the appearance of the base film layer does not deteriorate (it is finer than the printing provided in the base film layer). Hole is not noticeable). Thus, the gas-permeable laminated plastic film of the present invention capable of controlling gas permeability is suitable for use in lids such as containers for fermented foods such as kimchi, which constantly generates carbon dioxide gas.

  The apparatus for producing a gas permeable laminated plastic film of the present invention comprises a first perforation device for forming micropores on the sealant layer side, and a second perforation device for forming micropores on the base film layer side, By adjusting the characteristics of the perforating roll in the second perforating apparatus (area ratio and size of hard particles, width, interval and number of perforating rolls, pressing force of the perforating roll, etc.), fine holes on the base film layer side Therefore, various laminated plastic films having desired gas permeability can be formed.

It is a fragmentary sectional side view which shows the manufacturing apparatus of a gas-permeable laminated plastic film. It is a fragmentary top view which shows the manufacturing apparatus of the gas-permeable laminated plastic film of FIG. It is a partial front view which shows the manufacturing apparatus of the gas-permeable laminated plastic film of FIG. It is a top view which shows the detail of each 2nd punching apparatus. It is a front view which shows the detail of each 2nd punching apparatus. It is a top view which shows the detail of the holder in a 2nd punching apparatus. It is a fragmentary sectional side view which shows the operating state of the apparatus of this invention. It is a top view which shows the several belt-shaped 2nd micropore group formed in the base film layer side of a elongate laminated plastic film. It is AA sectional drawing of FIG. It is a top view which shows the gas-permeable laminated plastic film ribbon formed by slitting the gas-permeable long laminated plastic film of FIG. 8 at equal intervals for each second microhole group. FIG. 11 is an enlarged plan view showing a state in which a container lid is produced from the gas-permeable laminated plastic film ribbon of FIG. An example of the airtight container formed by heat-sealing the cover body which consists of a gas-permeable laminated plastic film of this invention to the flange of a container is shown, (a) is a top view, (b) is a side view.

[1] Production apparatus As shown in FIGS. 1 to 3, the production apparatus for a gas-permeable laminated plastic film of the present invention comprises: (a) the first from the upstream side along the moving direction of the long laminated plastic film 1; A first perforating apparatus 10 comprising one perforating roll 11 and a first surface smoothing roll 12 disposed at a position facing the first perforating roll 11, and (b) a second surface smoothing roll 22 A second perforating apparatus 20 comprising a plurality of second perforating rolls 21 arranged along the axial direction so as to face the second surface smoothing roll 22, and a long laminated plastic film 1 And a plurality of guide rails 30 (only one is shown).

  In the first perforating apparatus 10, a large number of hard particles having a Mohs hardness of 5 or more having sharp corners adhere to the entire surface of the first perforating roll 11. Such hard particles are preferably diamond fine particles. Diamond fine particles are adhered to the surface of the metal roll body by nickel plating or the like. The average particle size of the hard particles is appropriately determined according to the thickness of the sealant layer that forms the fine pores. For example, in order to form micropores having a depth similar to that of a sealant layer having a thickness of 45 μm, the average particle size of the hard particles is preferably 50 to 200 μm. The ratio (area ratio) of the hard particles on the surface of the first perforating roll 11 can be appropriately set according to the degree of gas permeability imparted to the laminated plastic film, but is generally 10 to 50%, preferably Is 15-30%. On the other hand, as the first surface smooth roll 12, a metal roll having a smooth surface can be used. In order to form sufficient fine holes, it is preferable that both the first perforating roll 11 and the first surface smoothing roll 12 are driven.

  In the second punching device 20, the second surface smoothing roll 22 is rotatably supported by a vertical frame 41 of the device downstream of the first punching device 10. In the illustrated example, five second perforating rolls 21 are arranged along the axial direction so as to face the second surface smoothing roll 22, but of course the number of second perforating rolls 21 is limited. Instead, it can be selected as needed. An apparatus 50 for driving the second perforating rolls 21 so that each second perforating roll 21 is movable in the axial direction and the radial direction of the second surface smoothing roll 22 (the gap direction between both rolls), The table 60 is movable in the axial direction of the second surface smoothing roll 22, the carrier 70 is movable along the guide rail 62 of the table 60 toward the second surface smoothing roll 22, and is supported by the carrier 70. And a holder 80 for rotatably supporting the second perforating roll 21 and measuring a load received by the second surface smoothing roll 22.

  As is apparent from FIGS. 1 to 4, a pair of guides 63 and 64 that engage with a pair of guide rails 43 and 44 provided on the upper surface of the horizontal frame 42 of the apparatus are provided on the lower surface of the table 60. Yes. As the guides 63 and 64, it is preferable to use linear motion (LM) guides. The table 60 is also provided with a linear clamp 55 that engages with the guide rail 44 to fix the position of the table 60 in the axial direction, and the linear clamp 55 is provided with a clamp arm 55a. After the guides 63 and 64 are moved to the desired position along the guide rails 43 and 44, when the clamp arm 55a is rotated, the linear clamp 55 is firmly engaged with the guide rail 44. The drive device 50 can be accurately positioned. Further, a driving motor 65 for the carrier 70 is fixed to the lower surface of the table 60 via a frame. In order to adjust the vertical position of the table 60, the horizontal frame 42 may be provided with a vertical movement mechanism.

  A carrier 70 that can move along the guide rail 62 of the table 60 includes a screw shaft 71 that is rotatably supported by the vertical frame 66 of the table 60, and a screw shaft 71 that is screwed into the screw shaft 71 to linearly rotate the rotation of the screw shaft 71. It has a nut member 72 that converts into motion, a carrier body 73 fixed to the nut member 72, and a guide 74 provided on the lower surface of the carrier body 73 so as to engage with the guide rail 62 of the table 60. The screw shaft 71 and the nut member 72 form a so-called ball screw. A pulley 76 connected to the motor 65 via a drive belt is provided at the rear end portion of the screw shaft 71. The guide 74 is also preferably an LM guide.

  As shown in FIG. 6, the holder 80 of the second perforating roll 21 includes a support 81 slidably provided in the holder main body 82 so as to rotatably support the second perforating roll 21, and a holder A load cell 83 provided in the main body 82 and a rod 85 fixed to the vertical frame 77 of the carrier 70 via a coil spring 84 are provided. The holder body 82 may be provided with a locking member (not shown) that prevents the support 81 from rotating. The front end portion of the support 81 is bifurcated, and the shaft 21a of the second perforating roll 21 is received and fixed with screws or pins. The rear end of the support 81 abuts on the load cell 83, and the load cell 83 measures the load received by the second punching roll 21. When the load received by the second perforating roll 21 exceeds a predetermined level, the coil spring 84 is compressed, the pressing force of the second perforating roll 21 against the second surface smoothing roll 22 is reduced, and the long laminated plastic film 1 or Damage to the device can be prevented.

  When processing fine holes in the long laminated plastic film 1 using this device, first, the sealant layer is turned up (the sealant layer is on the first punching roll 11 side), and the long laminated plastic film 1 is first punched. It is hung on the apparatus 10, the second surface smoothing roll 22 and the guide rail 30. The gap between the first perforating roll 11 and the first smooth surface roll 12 is adjusted so that the hard particles of the first perforating roll 11 sufficiently penetrate the sealant layer but hardly perforate the base film layer. .

  Next, after moving the guides 63 and 64 of the table 60 along the guide rails 43 and 44 on the frame 42 to a desired position in the axial direction of the second surface smoothing roll 22, the position of the table 60 is adjusted by the linear clamp 55. Fix it. Further, by operating the motor 65 and rotating the screw shaft 71 via the belt 75, each second punching roll 21 has a desired gap with respect to the second surface smoothing roll 22, as shown in FIG. Advance until you get it. Since the desired gap can be determined by the load applied to the second perforating roll 21, the advance position of the second perforating roll 21 is determined according to the signal obtained from the load cell 83. As shown in FIG. 7, the straight line connecting the center of the second perforating roll 21 and the center of the second surface smoothing roll 22 is preferably horizontal. When the long laminated plastic film 1 passes through the first and second perforating apparatuses 10 and 20 in this state, a first group of micropores is formed on the entire surface of the sealant layer, and a strip-shaped second film is formed on the base film layer. A group of fine holes is formed.

[2] Gas-permeable laminated plastic film FIGS. 8 and 9 show an example of the long gas-permeable laminated plastic film thus obtained. The laminated plastic film 1 is composed of a relatively thin base film layer 1a and a relatively thick sealant layer 1b, and on the side of the sealant layer 1b, deep micropores 2a, 2b formed by the first perforating device 10 ... The first micropore group 2 is formed, and on the base film layer 1a side, the second micropore group 3 consisting of shallow micropores 3a, 3b,. It is in.

(a) Base film layer The base film layer 1a is a layer that comes to the surface of the lid when it is used for a container lid, and since it is usually subjected to various printing, it needs to maintain a clean appearance. is there. Therefore, even if it is thin, it is formed of a resin having high strength and good printability. As such a resin, a polyester film such as polyethylene terephthalate (PET) is suitable. The PET film is a saturated polyester film composed of ethylene glycol and terephthalic acid. The thickness of the base film layer 1a is preferably 10 to 30 μm, more preferably 12 to 25 μm, and most preferably 12 to 20 μm.

  The fine holes 3a, 3b,... Provided in the base film layer 1a must have the same depth as the base film layer 1a. Here, “similar depth” means that the average depth of the fine holes 3a, 3b... Is 1 to 1.3 times the thickness of the base film layer 1a. Preferably it is 1-1.2 times, More preferably, it is 1-1.1 times. Area ratio of micropores 3a, 3b ... in second micropore group (band-like region) 3 (ratio of total opening area of micropores 3a, 3b ... to area of second micropore group 3) Is preferably 10 to 50%, more preferably 15 to 30%. The width of the second fine hole group (a band-like region formed by a large number of fine holes) 3 is determined by the roll width of the second perforated roll 21. Therefore, the area ratio of the second fine hole group (band-like region) 3 with respect to the entire laminated plastic film 1 can be adjusted in a wide range, for example, 5 to 30%, preferably 5 to 20%.

(b) Sealant layer The sealant layer 1b used for heat sealing the container body can be formed of, for example, low molecular weight polyethylene, unstretched polypropylene, ionomer resin, or the like. In addition, the sealant layer 1b preferably has an easy peel property so that the lid can be easily peeled off from the container body. Therefore, it is preferable that the sealant layer 1b has relatively weak thermal adhesiveness. The sealant layer 1b is a linear ethylene / α-olefin copolymer obtained by copolymerizing, for example, ethylene and an α-olefin having 3 to 18 carbon atoms [density: 0.870 to 0.910 g / cm ³ (JIS K6922 ), MFR (JIS K6921, 190 ° C., 2.16 kg load): 1 to 100 g / 10 min] and a resin composition containing polystyrene. Thereby, even if the sealing surface of a container main body is any of polyethylene or polystyrene, both the sealing performance and the easy opening performance can be achieved by the heat sealing of the lid.

  In order to ensure a sufficient heat seal, the sealant layer 1b is preferably 20-60 μm thicker than the base film layer 1a. A more preferable thickness of the sealant layer 1b is 30 to 50 μm. When the thickness ratio between the sealant layer 1b and the base film layer 1a is in the range of 1.5 / 1 to 5/1, the micropores on the sealant layer 1b side are enlarged and the micropores on the base film layer 1a side are reduced. As a result, the effect of the present invention can be sufficiently obtained to ensure gas permeability without deteriorating the appearance of the base film layer 1a. A preferred thickness ratio between the sealant layer 1b and the base film layer 1a is 2/1 to 4/1.

  The fine holes 2a, 2b,... Provided in the sealant layer 1b must have the same depth as the sealant layer 1b. Here, “similar depth” means that the average depth of the fine holes 2a, 2b... Is 0.95 to 1.1 times the thickness of the sealant layer 1b. Preferably it is 1-1.05 times, More preferably, it is 1 time. Since the sealant layer 1b is significantly more flexible than the base film layer 1a, it is relatively easy to form micropores only in the sealant layer 1b. The area ratio of the fine holes 2a, 2b... (The ratio of the total opening area of the fine holes 2a, 2b... To the total area of the film) is preferably 10 to 50%, and preferably 15 to 30%. Is more preferable.

(c) Through hole A part of the fine holes in the second fine hole group (band-like region) 3 provided in the base film layer 1a is the same as the fine holes in the first fine hole group 2 provided in the belt shape in the sealant layer 1b. It communicates and becomes a through hole. In FIG. 9, the fine holes 2a in the first fine hole group 2 and the fine holes 3a in the second fine hole group (band-like region) 3 communicate with each other. The degree to which the through holes are formed is adjusted by the area ratio and depth of the fine holes in the second fine hole group (band-like region) 3 and the width and number of the second fine hole group (band-like region) 3 Can do.

(d) for example, oxygen gas permeation amount as the gas permeability of the gas permeable gas permeable laminated plastic film 1 can be controlled in the range of 1,000~2,000,000 cc / m ^2/24 hours. The oxygen gas permeation amount was determined by forming a bag of gas permeable laminated plastic film 1, filling the interior with 100% nitrogen gas (1 atm), and leaving it in the atmosphere at 25 ° C. Measure by pouch method. The oxygen gas permeation amount is represented by the amount (cc) of oxygen gas permeating per unit area (1 m ² ) in 24 hours. The amount of carbon dioxide permeation is about 2 to 3 times the amount of oxygen gas permeation.

(e) Container lid As shown in FIG. 8, slit a long gas-permeable laminated plastic film 1 having a plurality of strip-shaped second microhole groups 3, and for example, as shown in FIG. A ribbon 4 having only the second fine hole group 3 is formed. Since this ribbon 4 has a pattern in which the design and characters for the lid are repeatedly printed in a line, as shown in FIG. 11, heat sealing and punching are simultaneously performed at a position aligned with the pattern, and the lid 5 is heated. Obtain a sealed container. In this example, each lid body 5 has one second fine hole group 3, but it goes without saying that two or more second fine hole groups 3 may be provided. As is apparent from FIG. 11, the lid 5 is formed from a part (particularly in the width direction) of the ribbon 4 formed by slitting the gas permeable laminated plastic film 1, so that the second group of micro holes in the lid 5 The area ratio of (band-like region) 3 is large, generally 10 to 50%, and preferably 15 to 40%.

  FIG. 12 shows an example of a sealed container obtained by heat-sealing the lid 5 on the flange of the container 6, wherein (a) is a plan view and (b) is a side view. A fine hole is formed on the entire surface of the sealant layer 1b on the back side of the lid 5, but it can be heat-sealed to the flange 6a of the plastic container 6 without any problem. 5a shows a heat seal portion of the lid 5. In this example, the second microhole group 3 passes through the tab 5b of the lid 5, but the position and number of the second microhole group 3 are not limited. A container formed by heat-sealing the lid body 5 on a plastic container 6 is suitable for fermented foods such as kimchi because the gas permeability can be adjusted by the second microhole group 3.

  The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

Example 1
Using the apparatus shown in FIG. 1, a first micropore group 2 is formed on the sealant layer side of a laminated plastic film 1 composed of a PET film layer having a thickness of 12 μm and a polyethylene sealant layer having a thickness of 50 μm. Then, the second micropore group 3 was formed on the PET film layer side. The average aperture diameter of the micropores in the first micropore group 2 was 20 μm, the depth was 50 μm, and the area ratio was 30%. The average aperture diameter of the micropores in the second microhole group (band-like region) 3 is 5 μm, the depth is 12 μm, the area ratio is 30%, and the second microhole group (band-like region) 3 The width of the film was 15 mm, and the area ratio of the second fine hole group (band-like region) 3 with respect to the total area of the film 1 was 7.5%.

On the side of the base film 1a of the obtained gas-permeable laminated plastic film 1 (the side that becomes the surface when used as a lid), fine pores were not noticeable and kept a beautiful appearance. The oxygen gas permeability of the gas permeable laminated plastic film results measured by the pouch method, was 300,000 cc / m ^2/24 hours. Moreover, when the plurality of lids made of the gas permeable laminated plastic film were each heat-sealed in a PET container and then the tabs were lifted, all of them could be peeled cleanly without breaking.

Example 2
A gas-permeable laminated plastic film 1 was produced in the same manner as in Example 1 except that the second perforating roll 21 was replaced and the width of the second microhole group (band-like region) 3 was changed to 20 mm. Second fine Anagun (band-like region) 3 area ratio of to the total area of the film 1 is 10%, the oxygen gas permeation amount measured by the pouch method was 400,000 cc / m ^2/24 hours.

Example 3
A gas-permeable laminated plastic film 1 was produced in the same manner as in Example 1 except that the second perforating roll 21 was replaced and the area ratio of the micropores in the second microhole group (band-like region) 3 was changed to 40%. did. Oxygen gas permeation amount measured by the pouch method was 400,000 cc / m ^2/24 hours.

Comparative Example 1
In the apparatus shown in FIG. 1, only the first perforating apparatus 10 was used to form fine holes penetrating the laminated plastic film 1 from the sealant layer 1b side. Despite the formation of the fine pores in the laminated plastic film 1 over the entire surface, the oxygen gas permeation amount measured by the same method as in Example 1 was less 100,000 cc / m ^2/24 hours. This is presumably because most of the fine holes do not penetrate the laminated plastic film 1. Moreover, the fine holes were conspicuous on the base film side 1a, and the beautiful appearance was not maintained. In addition, a plurality of lids made of this gas-permeable laminated plastic film were each heat sealed in a PET container, and then, when the tab was lifted, there were some which were broken.

Comparative Example 2
In the apparatus shown in FIG. 1, only the second perforation apparatus 20 was used to form a band-shaped second microhole group 3 composed of micropores penetrating the laminated plastic film 1 from the base film layer 1a side. The average aperture diameter of the micropores in the second microhole group (band-like region) 3 is 30 μm, the area ratio is 30%, and the width of the second microhole group (band-like region) 3 is 15 mm. The area ratio of the second fine hole group (band-like region) 3 to the total area of the film 1 was 7.5%. Oxygen gas permeation amount measured by the same method as in Example 1 was small and 10,000 cc / m ^2/24 hours. Moreover, the fine holes were conspicuous on the base film side 1a, and the beautiful appearance was not maintained. In addition, a plurality of lids made of the gas permeable laminated plastic film were each heat sealed in a PET container, and then the tab was lifted.

1 ... Laminated plastic film
1a: Base film layer
1b ・ ・ ・ Sealant layer
2 ... First micropore group
2a, 2b ... micropores in the first micropore group
3 ... second micropore group
3a, 3b ... micropores in the second micropore group
5 ... Cover body
5a ・ ・ ・ Heat seal
5b ... Tab
6 ... container
6a ・ ・ ・ Flange
10 ... First drilling device
11 ... First perforating roll
12. First surface smooth roll
20 ... Second punching device
21 ... Second perforation roll
22 ... Second surface smoothing roll
30 ... Guide rail
41 ... Vertical frame
42 ... Horizontal frame
43,44 ... Horizontal frame guide rail
50 ... Drive device for second punch roll
55 ・ ・ ・ Linear clamp
60 ... Table
62 ... Table guide rail
63, 64 ... Table guide
65 ... Motor for driving the carrier
66 ・ ・ ・ Vertical frame
70 ・ ・ ・ Career
71 ・ ・ ・ Screw shaft
72 ... Nut member
73 ・ ・ ・ Carrier body
74 ... Career guide
75 ・ ・ ・ Drive belt
76 ... Pulley
77 ・ ・ ・ Vertical frame
80 ... Holder of second punch roll
81 ... Support
82 ... Holder body
83 ... Load cell
84 ・ ・ ・ Coil spring
85 ... Rod

Claims (5)

It consists of a laminated plastic film of a base film layer having a thickness of 12 to 25 μm and a sealant layer having a thickness of 30 to 50 μm, and the thickness ratio of the sealant layer and the base film layer is 1.5 / 1 to 5 / A gas permeable laminated plastic film in the range of 1, wherein the first of the sealant layer side formed from both sides of the laminated plastic film by a perforating roll having a number of hard particles having sharp corners attached to the surface And the second fine hole group on the base film layer side, the first fine hole group covers the entire surface of the sealant layer and has the same depth as the sealant layer, the second fine Anagun has the base film layer and the same degree of depth covers a strip of the base film layer partially, both in the region where the first and second fine hole groups overlap Fine A gas permeable laminated plastic film characterized in that the pores pass through the laminated plastic film by communicating to provide gas permeability. In the gas-permeable laminated plastic film according to claim 1, wherein the gas permeability, the area ratio and the depth of the micropores in said second fine Anagun, as well as the width and number of the second fine hole groups A gas permeable laminated plastic film characterized by being adjusted. An apparatus for producing a gas permeable laminated plastic film according to claim 1 or 2 , comprising first and second perforating devices arranged along the moving direction of the laminated plastic film, (a) The first perforating apparatus includes a first perforating roll disposed on the sealant layer side, and a position facing the first perforating roll, with a large number of hard particles having sharp corners attached to the surface. (B) the second perforating apparatus has a second surface smoothing roll that rotates at a fixed position on the sealant layer side, and a number of sharp corners. A plurality of second perforating rolls arranged along the axial direction so that the hard particles adhere to the surface and face the second smooth surface roll, the laminated plastic film comprises First Passing through the gap between the first perforated roll and the first surface smooth roll and the gap between the second perforated roll and the second surface smooth roll, the first micropore group is formed on the entire surface of the sealant layer. A device for producing a gas permeable laminated plastic film, characterized in that a plurality of second fine hole groups are partially formed in a band shape in the base film layer. 4. The apparatus for producing a gas permeable laminated plastic film according to claim 3 , wherein the second perforated roll is movable with respect to the second surface smooth roll, and thus the width and number of the second fine hole group. And the area ratio and depth of the micropore in said 2nd micropore group can be adjusted, The manufacturing apparatus of the gas-permeable laminated plastic film characterized by the above-mentioned. 5. The apparatus for producing a gas permeable laminated plastic film according to claim 4 , wherein the device for driving the second perforated roll includes a table movable in an axial direction of the second surface smoothing roll, and a guide for the table. A carrier that is movable in the direction of the second surface smoothing roll along the carrier, and a holder that is supported by the carrier and that rotatably supports the second perforating roll. Means for detecting the load applied to the perforating rolls, and controlling the distance between the second perforating roll and the second surface smoothing roll in accordance with the load; An apparatus for producing a gas permeable laminated plastic film, wherein the area ratio and depth of the holes are adjusted.

Images