JP6536878B2 - Multiple bag - Google Patents

Description

  The present invention relates to multiple bags. More specifically, the present invention relates to a multiple bag which is used for a so-called back-in box or the like, and which can pack, carry, etc. predetermined contents such as materials, foods and the like.

  Conventionally, materials such as liquids, semi-liquids, powders, solids, pastes and the like used for commercial use have been filled in metal containers and used for transportation, storage, sales and the like. On the other hand, metal containers have problems such as bulky containers after use, difficulty in taking out contents, difficulty of container processing after use, heavy weight of containers, and the like.

  In recent years, a so-called bag-in-box packaging method has been widely put to practical use, in which such contents are filled in a bag made of a synthetic resin film and stored in a cardboard box or pallet and circulated. In such a bag-in-box, it is required that the mechanical strength of the film for the bag be high, and a film in which a layer having heat fusion property is laminated on a high strength film such as nylon or polyester is used. In addition, although attempts have been made to laminate films other than the above or to increase the thickness in order to further increase the mechanical strength, in reality it has not been possible to solve the problem by increasing the thickness of the film alone.

  Therefore, a multiple bag has been proposed in which two films forming the bag are not completely laminated, and there is a degree of freedom in which they can move relative to each other (see, for example, Patent Document 1). This multiple bag (also called a double bag) consists of an outer film that appears on the outside and an inner film that contacts the contents, and can prevent other films from being damaged if pinholes occur in one film. . Also, even with respect to bending stress, a certain degree of slippage can be generated between the inner film supporting the contents and the outer film supporting the multiple bag in contact with the cardboard box etc. Is absorbed to suppress the application of extreme bending stress and to prevent the occurrence of pinholes or rupture of the bag in the film forming the bag.

Patent No. 4490045

  When taking out the contents filled, the multiple bag is often torn open from the back seal part and opened, for example, in the case where the back seal part is formed on such a palm part as a bond at the palm part. There is a problem that the openability is not good, including the need to tear the four seals collected in the palm part, and the freedom to allow the outer film and the inner film to move relative to each other. It was rare.

  The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide, for example, a multiple bag which can be used as a back-in box or the like and which is excellent in easy opening property.

In order to solve the above-mentioned problems, a multiple bag according to the first invention of the present invention is a multiple bag composed of a multiple film consisting of an outer film and an inner film, wherein both ends of the multiple film are the inner films And a back seal portion integrally formed by welding all the outer films and the inner film to be overlapped with each other at a predetermined width. A lateral seal is formed by welding with a predetermined width around both end edges on the side orthogonal to the back seal, thereby forming a multi-layered bag in which the contents are filled and sealed. And a tear start portion formed substantially parallel to the transverse seal portion for tearing open substantially parallel, and the tear start portion is at least the back seal portion from the outer edge of the combined palm portion. Until Characterized in that it is formed so as to.

  In the multiple bag according to the first aspect of the present invention, in the first aspect described above, the back seal portion is formed in a plurality of narrow lines with respect to the combined palm portion, and the tear start portion is the plurality of back seal portions It is characterized in that it is formed to reach at least the back seal portion formed on the outer edge side of the combined palm portion.

  In the multi-layer bag according to the first aspect of the present invention, in the above-mentioned first aspect, the multi-layer film is a flat sheet of a tube-shaped film, and two stacked sheets. It is characterized by comprising a film.

  In the multiple bag according to the first invention of the present invention, in the above-mentioned first invention, the outer film is composed of a layer consisting of linear low density polyethylene, an easily tearable resin layer, and a polyolefin resin sequentially from the outer side of the multiple bag. The inner film is composed of a resin layer, and the inner film is composed of a layer composed of a polyolefin resin / a tearable resin layer / a layer composed of linear low density polyethylene in order from the outside of the multiple bag.

  In the multiple bag according to the first invention of the present invention, in the first invention described above, the easily tearable resin layer is made of a mixed resin containing 3 to 99% by mass of cyclic polyolefin with respect to the entire easy tear resin layer. I assume.

The multiple bag according to the second invention of the present invention is a multiple bag composed of a multiple film consisting of an outer film and an inner film, and the two ends of the multiple film are superposed so that the inner films face each other. A back seal portion is formed by welding all integral outer and inner films with a predetermined width to the combined palm portion to form a back seal portion, and both ends on the side orthogonal to the back seal portion A multi-layer bag in which the contents are filled and sealed is formed by forming a transverse seal portion having a predetermined width welded to the vicinity of the edge, and the joint palm portion tears substantially parallel to the transverse seal portion. for opening, has a tear initiation portion which is substantially formed parallel to the lateral sealing portion, at least said outer film is made of a mixed resin of a cyclic polyolefin resin and a polyolefin resin Characterized in that it is a multi-layer structure having between layers.

  In the multi-layer bag according to the second aspect of the present invention, in the above-mentioned second aspect, the multi-layer film is a flat sheet of a tube-shaped film, and two stacked sheets. The film is characterized in that the outer film and the inner film have the intermediate layer.

  In the multiple bag according to the second invention of the present invention, in the above-mentioned second invention, the multiple film is formed by blocking adhesion between the surface of the inner film in contact with the outer film and the surface of the outer film in contact with the inner film. And a blocking adhesive film.

  The multiple bag according to the second invention of the present invention is characterized in that, in the above-mentioned second invention, the mixed resin contains 3 to 99% by mass of the cyclic polyolefin resin with respect to the whole of the mixed resin.

  In the multiple bag according to the first aspect of the present invention, the tear start portion formed on the palm of the multiple bag formed of the multiple film consisting of the outer film and the inner film extends from the outer edge of the double palm to at least the back seal. As a result, the multi-layer bag can be easily opened and the multi-layer bag can be easily opened.

  Further, in the multiple bag according to the second invention of the present invention, at least the outer film of the multiple bag composed of the multiple film consisting of the outer film and the inner film is an intermediate layer composed of a mixed resin of cyclic olefin resin and polyolefin resin. As a result, the multi-layer bag can be easily teared and has an easy-to-open property.

1 is a perspective view of a multiple bag according to the present invention. It is a front view showing a multiple bag according to the present invention. It is the schematic which showed the state which curved the multiple film (tube-like film) in the shape of a cylinder, and piled up, and formed the convoluted part. It is an enlarged view of a back seal part at the time of using a tube-like film. It is the schematic which showed the state which curved the multiple film (blocking adhesive film) in the shape of a cylinder, and piled up, and formed the convoluted part. It is an enlarged view of a back seal part at the time of using a blocking adhesive film. It is the front view which showed the other aspect of the multiple bag which concerns on this invention. In a tubular film, it is sectional drawing which showed the layer structure at the time of using an inner film and an outer film as three layers. In a blocking adhesive film, it is sectional drawing which showed the layer structure at the time of making an outer side film into three layers.

  Hereinafter, one aspect of the multiple bag 1 according to the present invention will be described.

(A) Configuration of Multiple Bag 1 (First Embodiment (First Invention), Second Embodiment (Second Invention)):
Hereinafter, the multiple bag 1 according to the present invention will be described. 1 is a perspective view showing a multiple bag 1 according to the present invention, FIG. 2 is a front view showing a multiple bag 1 according to the present invention, and FIG. 3 is a tubular film of a multiple film 2 (tube-like film 21). , And FIG. 4 shows an enlarged view of the back seal portion 6 when the tubular film 21 is used. In the figure, 1 is a multiple bag, 2 is a multiple film, 3 is an outer film, 4 is an inner film, 5 is a chasing portion, 51 is a tear initiation portion, 52 is an outer edge of the chasing portion, 6 is a back seal portion, 61 is a chasing arm The back seal part formed at the outer edge 52 side of the part, 7 shows a horizontal seal part, respectively.

  The multiple bag 1 shown in FIGS. 1 and 2 is constituted by a multiple film 2 consisting of an outer film 3 and an inner film 4. The outer film 3 and the inner film 4 appear on the outer side of the multiple bag 1 (in contact with a cardboard box (not shown) or the like) when the multiple bag 1 is formed as a bag, and the inner film 3 and the inner side of the multiple bag 1 The film (contacting the content not shown) appearing in FIG.

  As shown in FIG. 3, the palm portion 5 constituting the multi-layer bag 1 is formed by curving the multi-layer film 2 in a cylindrical shape and superposing the both ends of the multi-layer film 2 such that the inner films 4 face each other. .

  The multiple bag 1 is filled with predetermined contents at the time of use, and the back seal portion 6 and the lateral seal portion 7 are formed, whereby the contents are filled and sealed. As shown in FIG. 1 and FIG. 2, the back seal portion 6 is welded (heat seal, heat seal) in a band shape with a predetermined width (approximately 2 to 20 mm, the same applies hereinafter) with respect to the combined palm portion 5. The same shall apply hereinafter. In addition, the lateral seal portion 7 is formed by welding in the form of a band having a predetermined width (approximately 2 to 20 mm or so, hereinafter the same) in the vicinity of both end edges on the side orthogonal to the back seal portion 6. The lateral seal portion 7 may be formed of a plurality of narrow linear linear seal portions.

  Both the back seal portion 6 and the horizontal seal portion 7 are formed by bringing the inner films 4 of the multiple film 2 into contact with each other in a flat state and sandwiching them from outside with a seal bar or the like having a predetermined width not shown. Although FIG. 4 shows an enlarged view of the back seal portion 6, all the films (two outer films and two inner films) to be overlapped including the outer films 3 in addition to the inner films 4 in contact with each other. 4 pieces are welded and integrated. This is also true for the lateral seal portion 7.

  In addition, FIG.3 and FIG.4 has shown the aspect using the tube-shaped film 21 demonstrated by (B) (1) and (C) (1) later mentioned as a structure of the multiplex film 2. As shown in FIG. In the tubular film 21, the outer film 3 and the inner film 4 are integrated, and both side edges of the outer film 3 and the inner film 4 are continuous with each other.

  On the other hand, in the case of using the blocking adhesive film 22 described in (B), (2) and (C), (2) described later as the configuration of the multiplex film 2, the following occurs. FIG. 5 is a schematic view showing a state in which the multiple film 2 (blocking adhesive film 22) is curved in a cylindrical shape and stacked to form the combined palm portion 5, and FIG. 6 is a case where the blocking adhesive film 22 is used. It is an enlarged view of back seal part 6 in a. Thus, the blocking adhesive film 22 differs from the tubular film 21 in that the outer film 3 and the inner film 4 are not integrated, and both side edges of the outer film 3 and the inner film 4 are not continuous with each other.

(B) Multiple bag 1 according to the first embodiment:
Hereinafter, the configuration of the multiple bag 1 according to the first embodiment will be described. As shown in FIGS. 1 and 2, the multiple bag 1 according to the first embodiment of the present invention is a tear-off with respect to the palmar part 5 in which both ends of the multiple film 2 are overlapped such that the inner films 4 face each other. The start part 51 is formed. The tear start portion 51 is formed to be opened substantially parallel to the lateral seal portion 7, and for example, if formed so as to be substantially parallel to the lateral seal portion 7, the user can open the lateral seal portion 7. In contrast, it becomes easy to open almost parallel.

  The tear start part 51 formed in the joint part 5 weakens the initial tear strength and improves the easy opening property. The tear start part 51 can be made into arbitrary shapes, such as a slit (break), a V notch, an I notch, a perforation, a microporous aggregate, and the like.

  The tear start portion 51 is formed to reach at least the back seal portion 6 from the outer edge 52 of the combined palm portion, as shown in FIGS. 1 and 2. Since the tear start portion 51 has reached the back seal portion 6, the tearing can be smoothly taken out at the time of opening, and the back seal portion 6 in which four films (two multiplexed films 2) are gathered is easy It becomes the multiple bag 1 excellent in easy openability which can be torn. The length of the tear start portion 51 is not particularly limited as long as it reaches the back seal portion 6 as described above, but it may be approximately 5 to 20 mm.

  FIG. 7 is a front view showing another aspect of the multiple bag 1. FIG. 7 shows an aspect in which two back seal parts 6 are formed in a narrow line shape with respect to the aikomo part 5. Thus, in the case where a plurality of narrow linear back seal portions 6 are formed, the tear start portion 51 is formed at least on the outer edge 52 side of the combined palm portion among the plurality of narrow linear back seal portions 6 It is formed to reach the back seal portion 61. In the present invention, the narrow linear back seal parts 6 and 61 indicate the substantially straight back seal parts 6 each having a width of about 2 to 10 mm by heat sealing (welding). . In addition, the number of the plurality of back seal parts 6, 61 may be approximately 2 to 5.

(1) Configuration of Multiplexed Film 2 (Tube-like Film 21):
Next, the multiple film 2 constituting the multiple bag 1 will be described. With regard to the multiple film 2, although the outer film 3 and the inner film 4 are two-ply laminated, for example, two opposing two-ply cylindrical films are closed facing each other in a bag shape. A sheet of film (tube-like film 21) can be used. The tube-like film 21 which is the multiple film 2 is a film in which both side edges of the outer film 3 and the inner film 4 are continuous with each other as shown in FIGS. 3 and 4. Are integrated. Thus, the outer film 3 and the inner film 4 are made of a common resin.

  The tube-shaped film 21 preferably has a multilayer structure. Hereinafter, a tube-shaped film 21 in which the outer film 3 and the inner film 4 have a common three-layer structure will be described as an example.

  FIG. 8 is a cross-sectional view showing the layer structure in the case where the outer film 3 and the inner film 4 are three layers in the tube-like film 21. As shown in FIG. In FIG. 8, 3 indicates an outer film, 4 indicates an inner film, 31 and 41 indicate inner layers, 32 and 42 indicate intermediate layers, 33 and 43 indicate outer layers, and C indicates a gap.

  As shown in an example in FIG. 8, in the case of forming the outer film 3 and the inner film 4 in multiple layers, the outer film 3 and the inner film 4 can be seen from the clearance C formed between the outer film 3 and the inner film 4. From the outside of the multiple bag 1 to the inside of the multiple bag 1 in a symmetrical relationship, the outer / outer layer 33 / intermediate layer 32 / inner layer 31 (the above is a layer of the outer film 3) / gap C / inner layer 41 of the multiple bag 1 / Intermediate layer 42 / outer layer 43 (the above is the layer of the inner film 4) / inside of the multiple bag 1. And when forming the back seal part 6 and the horizontal seal part 7, the layer applicable to the outer layers 33 and 43 will be piled up, will be directly contacted and welded.

  Among the layers described above, the outer layers 33 and 43 that are welded in direct contact when forming the back seal portion 6 and the lateral seal portion 7 preferably have heat sealability in the layer itself, for example, a polyolefin resin Specifically, high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE), linear (linear) low density polyethylene (LLDPE), linear ultra low density Polyethylene (VLDPE), copolymers of vinyl compounds copolymerizable with ethylene, such as ethylene-vinyl acetate copolymer (EVA), ionomers, ethylene-acrylic acid or ethylene-acrylic acid ester copolymers, Polyethylene such as ethylene methacrylic acid or methacrylic acid ester copolymer, ethylene-propylene copolymer, etc. Polyolefin resins such as acid-modified polyolefin resins such as acrylic resins, polypropylene resins, and polyolefin resins such as polyethylene and polypropylene modified with acrylic acid, methacrylic acid, maleic anhydride, fumaric acid, and other unsaturated carboxylic acids Can be mentioned. One of these resins may be used alone, or two or more thereof may be used in combination.

  Among these resins, it is preferable to use low density polyethylene (LDPE) which is excellent in heat sealability etc. Among low density polyethylenes, it has pinhole resistance and is tough and strong, so it has mechanical strength etc. It is particularly preferred to use linear low density polyethylene (LLDPE) which is also excellent.

  Physical properties, mechanical strength, heat seal strength and the like when using linear low density polyethylene (LLDPE) are adjusted by the number of carbons of the α-olefin to be copolymerized. Generally, α-olefins having 3 to 13 carbon atoms, preferably 4 to 8 carbon atoms, such as butene-1, octene-1, hexene-1, 4-methylpentene-1, hexene-1 and the like are preferably used. Be

The density of the low density polyethylene (including linear low density polyethylene) is preferably 0.870 to 0.935 g / cm ³ . Various properties such as heat sealability are maintained by using the low density polyethylene in the density range. The density of the low density polyethylene is particularly preferably 0.880 to 0.920 g / cm ³ . The melt flow rate (MFR) at 190 ° C. is preferably 0.1 to 30.0 g / 10 min, and particularly preferably 0.5 to 4.0 g / 10 min.

  The inner layers 31 and 41 and the intermediate layers 32 and 42 constituting the outer film 3 and the inner film 4 in FIG. 8 have the above-mentioned polyethylene resin and polypropylene resin in order to impart pinhole resistance and mechanical properties to the multilayer film 2. In addition to polyolefin resins such as resins, polyamide resins (nylon), polyester resins (PET, PBT), ethylene-vinyl alcohol copolymers and the like can be used.

  The intermediate layers 32 and 42 may be made of an easily tearable resin layer made of an easily tearable resin. By interposing the easily tearable resin as the intermediate layers 32 and 42, the multiple film 2 can be further provided with easy openability. When the outer film 3 and the inner film 4 have the three-layer structure shown in FIG. 8, the outer film 3 is a layer made of linear low density polyethylene (linear low density) in order from the outer side of the multiple bag 1. Density polyethylene layer) / easy tear resin layer / layer (polyolefin resin layer) composed of polyolefin resin, inner film 4 is polyolefin resin layer / easy tear resin in order from the outside (the above described gap C) of the multiple bag 1 It is preferable to use a layer / linear low density polyethylene layer. By making the outer film 3 and the inner film 4 in such a configuration, easy openability (easy tearability) can be imparted while maintaining heat sealability, pinhole resistance, and the like.

  As resin which comprises an easily tear resin layer, you may make it use mixed resin containing cyclic polyolefin resin, for example. By interposing the layer containing the cyclic polyolefin resin as the intermediate layers 32 and 42, the easy opening property (easy tearability) of the multiple film 2 is improved.

  The cyclic polyolefin resin is a generic name of a resin which is generally polymerized by using cyclic olefin as a polymerization unit, and described, for example, in JP-A-1-240517, JP-A-3-14882 and JP-A-3-122137. It is done. In the present invention, a ring-opening metathesis polymer (also referred to as a cyclo-olefin polymer (COP: Cyclo-Olefin Polymer)) obtained by polymerizing a cyclic olefin by a metathesis ring-opening polymerization reaction, as well as cyclic olefins and α-olefins. So-called cyclic olefin copolymers (also referred to as cyclo-olefin copolymers (COC: Cyclo-Olefin Copolymer)) which are copolymers with (chain olefins) etc., and graft weights obtained by modifying these with unsaturated carboxylic acids and their derivatives It is intended to include coalescence, hydrides thereof and the like.

  As the cyclic olefin, any cyclic hydrocarbon having an ethylenically unsaturated bond and a bicyclo ring can be used, and norbornene monomers and the like are widely known, and bicyclo [2.2.1] hepta-2- Those having an ene (norbornene) skeleton are preferred.

Specifically, bicyclo [2.2.1] hept-2-ene and derivatives thereof, tricyclo ^[4.3.0.1 2.5]-3-decene and derivatives thereof, tricyclo [4.4.0 .1 ^2.5 ] -3-undecene and its derivatives, tetracyclo [4.4.0.1 ^2.5 . 1 ^7.10 ] -3-dodecene and its derivatives, pentacyclo [6.5.1.1 ^3.6 . 0 ^2.7 . 0 ^9.13] -4-pentadecene and its derivatives, pentacyclo ^{[7.4.0.1 2.5 .1 9.12 .0 8.13]} -3- pentadecene and derivatives thereof, pentacyclo [6.5. 1.1 ^3.6 . 0 ^2.7 . 0 ^9.13] 4,10 penta decadiene and its derivatives, pentacyclo [8.4.0.1 ^2.5 .1 ^{9.12. 8.13} ] -3-hexadecene and its derivatives, etc., but not limited thereto.

  In addition, cyclic olefin includes, as a substituent, for example, carboxyl group, acid anhydride group such as carboxylic acid anhydride, epoxy group, amino group, amido group, ester group, hydroxyl group, sulfo group, phosphono group, phosphino group, etc. It may have a polar group of In addition, (meth) acrylic acid, maleic acid, maleic anhydride, itaconic anhydride, glycidyl (meth) acrylate, alkyl (meth) acrylate (for example, having 1 to 10 carbon atoms) ester, alkyl maleate (for example, carbon number) 1-10) Ester, (meth) acrylamide, (meth) acrylic acid 2-hydroxyethyl etc. can be mentioned, Preferably, a carboxyl group, an acid anhydride group, an epoxy group, an amino group, an amide group, ester group is preferable. It may have an unsaturated compound having a polar group such as a hydroxyl group, a sulfo group, a phosphono group or a phosphino group.

  For example, as the cyclic olefin copolymer, as α-olefin copolymerized with cyclic olefin, for example, ethylene, α-olefin having 3 to 20 carbon atoms can be used, and specifically, ethylene, propylene, 1- A butene, 1-pentene, 3-methyl- 1-butene, 1-hexene, 4-methyl- 1-pentene etc. are mentioned, Ethylene etc. are used widely.

  When a polyethylene-based resin is used as the resin (described later) to be combined with the cyclic polyolefin resin, it is preferable to use a cyclic olefin copolymer (COC), for example, because the dispersibility in polyethylene becomes good. It is particularly preferable to use an ethylene-cyclic olefin copolymer where ethylene is ethylene.

  In the present invention, production of the ring-opening metathesis polymer is not particularly limited as long as it is a known ring-opening metathesis polymerization reaction, and can be produced by ring-opening polymerization of the cyclic olefin described above using a polymerization catalyst. .

  The production of the cyclic olefin copolymer is carried out, for example, by randomly polymerizing α-olefin and cyclic olefin at a predetermined molar ratio using a single site catalyst such as a metallocene catalyst or a multisite catalyst.

  Further, a hydrogenated product such as a ring-opening polymer of a cyclic olefin monomer can be obtained by hydrogenating the ring-opening polymer with a known hydrogenation catalyst.

As the cyclic polyolefin resin, it is preferable to use one having a glass transition temperature (T _g ) (for example, JIS K 7121 or the like) of 60 ° C. or more. Excellent heat resistance can be maintained by using a cyclic polyolefin resin in a range in which the glass transition temperature is in such a range. The cyclic polyolefin resin particularly preferably has a glass transition temperature (T _g ) of 70 ° C. or higher.

  The melt flow rate (MFR) of the cyclic polyolefin resin is preferably 3.0 to 30.0 g / 10 min. Excellent heat resistance can be maintained by using the cyclic polyolefin resin in such a range as MFR. The MFR of the cyclic polyolefin resin may be a value measured in accordance with ISO 1133 or ASTM D-1238 (for example, 280 ° C., 21.18 N). The MFR of the cyclic polyolefin resin is particularly preferably 5.0 to 20.0 g / 10 min.

  In the case where the intermediate layers 32 and 42 are made to be the above-mentioned mixed resin, as the resin which can be used in combination with the cyclic polyolefin resin, it is possible to use the above-mentioned polyethylene resin or polyolefin resin such as polypropylene resin. Among these, polyethylene resins are preferable, low density polyethylene (LDPE) is more preferable, and linear low density polyethylene (LLDPE) is particularly preferable.

  The content of the cyclic polyolefin resin in the mixed resin constituting the easily tearable resin layer is 3 to 99 mass based on the entire mixed resin (refers to the total of the cyclic polyolefin resin and the resin used in combination with the cyclic polyolefin resin). It is preferable to use%. By setting the content of the cyclic polyolefin resin in such a range, the easy tearability is favorably implemented. The content of the cyclic polyolefin resin is more preferably 60 to 90% by mass, particularly preferably 60 to 80% by mass, with respect to the entire mixed resin.

  In addition, although it is preferable to set it as the intermediate | middle layers 32 and 42 in the outer side film 3 and the inner side film 4 of a multilayer which are comprised with the mixed resin mentioned above in the outer side film 3 and the inner side film 4 of a multilayer, When the film 4 is a multilayer, there is no problem as a layer other than the intermediate layers 32 and 42.

  In order to produce the tube-shaped film 21 which is the multiple film 2, for example, it is preferable to obtain it by the inflation film method. The inflation film has a tubular shape (tubular shape) in advance, can be used as manufactured, and has the merit that the film does not have to be cylindrical in a later step and no seam is generated. In addition, the inflation film can easily produce a relatively thick film as well as a thin film.

  As a general inflation film method, for example, a molten resin extruded in the form of a tube from an extruder through a die is vertically pulled up, and the molten resin is expanded by air supplied in the process of being pulled up vertically, and the tube is expanded. By rolling the film into a flat film while air cooling it and winding it around a winding device, it is possible to obtain a roll in which the tubular film 21 is wound flat.

  In the case where the multiple film 2 is a tube-like film 21, the layers (inner layers 31 and 41 in FIG. 8 described above) which do not appear on the outer side of the outer film 3 and the inner film 4 but contact each other mutually block. It is preferable to adhere. Here, "blocking and adhering to each other" means that the films in contact with each other are not completely integrated by bonding them with other media such as an adhesive or by heat fusion, but are in contact with each other. These films are pseudo-bonded to each other in a flexible state. Blocking adhesion may occur over the entire surface of the film or may partially occur on a part of the film. By blocking adhesion, the outer film 3 and the inner film 4 are integrated at the time of bag making or the like, and the handleability is improved.

  In order to block and bond the tubular film 21, for example, the tubular film made of a polyolefin based film formed by the above-mentioned inflation film method is pressed by a folding nip roll or the like to push out air between the superposed films. It can manufacture simply by winding up as a flat two-layer film.

(2) Configuration of Multiple Film 2 (Blocking Adhesive Film 22):
Next, another configuration of the multiplex film 2 will be described. As the multi-layer film 2, it is possible to use one (blocking adhesive film 22) in which the separately independent outer film 3 and the inner film 4 are bonded by blocking.

  Here, the “blocking adhesion” is as described above, and the films in contact with each other are not completely integrated by bonding them with another medium such as an adhesive or heat fusion, and are not films. It indicates that the films in contact with each other are in a pseudo-adhesive state and in a flexible state. Blocking adhesion may occur over the entire surface of the film or may partially occur on a part of the film. By blocking adhesion, the outer film 3 and the inner film 4 are integrated at the time of bag making or the like, and the handleability is improved.

  The blocking adhesive film 22 to be the multi-layer film 2 is a film consisting of a layer consisting of the outer film 3 and the inner film 4 (hereinafter, may be referred to as a "blocking adhesive layer") which is blocking bonded. The film which laminated | stacked the further layer as the outer side film 3 in a layer is also included.

  FIG. 9 is a cross-sectional view showing the layer configuration in the case of forming three layers of the outer film 3 in the blocking adhesive film 22. In FIG. 9, 3 is an outer film, 4 is an inner film, 31 is an inner layer, 32 is an intermediate layer, 33 is an outer layer, and B is a surface on which blocking adhesion is performed. As shown in FIG. 9, in the blocking adhesive film 22, the surface of the inner film 4 in contact with the outer film 3 and the surface of the layer constituting the outer film 3 in contact with the inner film 4 (the surface of the inner layer 31) are blocked It will adhere. Moreover, in the blocking adhesive film 22, when the back | inner seal | sticker part 6 and the horizontal seal | sticker part 7 are comprised, the inner film 4 will be piled up and will be directly contacted and welded.

  The resin (the inner film 4 and the inner layer 31 of the outer film 3) constituting the blocking adhesive layer in the blocking adhesive film 22 preferably has heat sealability, and, for example, the polyethylene resin mentioned in (1) above And polyolefin resins such as polypropylene resins can be used. Further, among such polyolefin resins, it is preferable to use a polyethylene resin, and among these, it is more preferable to use low density polyethylene (LDPE) which is excellent in heat sealability etc., and linear low density polyethylene (LLDPE). It is particularly preferred to use

  Moreover, as a resin which comprises the outer layer 33 in the outer side film 3, and the intermediate | middle layer 32, in order to provide pinhole resistance and mechanical characteristics to the multiple film 2, for example, the polyethylene-type resin mentioned above by (1) or In addition to polyolefin resins such as polypropylene resins, for example, polyamide resins (nylon), polyester resins (PET, PBT), ethylene-vinyl alcohol copolymers and the like can be used.

  Moreover, it is preferable to form the easily tearable resin layer which consists of easily tearable resin as the intermediate | middle layer 32 of the outer side film 3 similarly to the tube-like film 21 mentioned above. As the easily tearable resin layer, for example, a layer made of a mixed resin of a cyclic polyolefin resin and a polyolefin resin may be used. By interposing the layer containing the cyclic polyolefin resin as the intermediate layer 32, the easy openability (the easy tearability) of the multilayer film 2 is improved. About content of a cyclic polyolefin resin which can be used, polyolefin resin, and cyclic polyolefin resin etc., since it is in common with mixed resin etc. containing cyclic polyolefin resin explained by (1) mentioned above, explanation is omitted.

  When using the blocking adhesive film 22 as the outer film 3 having the three-layer structure shown in FIG. 9, the outer film 3 is a layer made of a polyolefin resin (polyolefin resin layer) in order from the outside of the multiple bag 1 / Layer consisting of mixed resin of cyclic polyolefin resin and polyolefin resin (mixed resin layer) / Layer consisting of linear low density polyethylene (linear low density polyethylene layer), inner film is linear low density polyethylene layer It is preferable to By making the outer film 3 and the inner film 4 in such a configuration, easy openability (easy tearability) can be imparted while maintaining heat sealability, pinhole resistance, and the like.

  The layer made of a mixed resin of a cyclic polyolefin resin and a polyolefin resin has no problem as a layer other than the intermediate layer 32 in the multilayer outer film 3 and is similar to the tube-like film 21.

  There is no particular limitation on the method for forming the blocking adhesive layer to be blocked and adhered, and conventionally known techniques can be used. For example, the tubular film extruded when the inflation film is produced by the single layer extrusion inflation method is folded The film can be manufactured by, for example, a method of laminating on a take-up nip roll or a press-fit roll newly provided after the take-up nip roll, press-contacting on-line to block the inner surfaces of the film and taking it in a roll. As another method, a film which is separately wound without blocking is extracted off-line in an off-line manner, layers to be blocked are superposed and aligned, and thermocompression bonding is carried out through blocking between heated pressure rolls, etc. However, in terms of simplicity of operation, cost and the like, it is preferable to use the above-described method of compression bonding and blockinking simultaneously with the above-described inflation molding.

  Here, the ease of blocking adhesion is appropriately changed depending on the type and density of the resin (polyolefin resin and the like) used, and the type and amount of additives such as a lubricant and an antiblocking agent. Generally, the higher the density of the resin, the more difficult the blocking the greater the amount of additive. Also, in order to adjust the blocking adhesive strength of the film formed and folded by the inflation method, the film before the folded tube-like film passes rolls such as a nip roll, a pressure roll, an embossing roll, a heating roll, etc. May be heated using a heating means such as a far infrared lamp or a nichrome wire heater.

  The adhesive strength of the two layers for blocking adhesion should be at least a level that does not cause unintended peeling of blocking in the film laminating step, slitting step, bag making or automatic filling and bag making step and does not impair the mechanical suitability. . About this, it is also the same as when blocking-adhering inner layers 31 and 41 comrades with said (1) tube-like film.

  In order to laminate the blocking adhesive layer and the other layers, for example, a dry lamination method, a solventless lamination method, a hot melt lamination method, an extrusion lamination method or the like in which adhesion is performed via a predetermined adhesive or adhesive resin is used. For example, in the case of the dry lamination method, although it is general to use a one-component or two-component polyurethane adhesive, the invention is not limited thereto, depending on the type of resin constituting the layer to be laminated, etc. The type of adhesive may be selected appropriately. As the adhesive resin, known adhesive resins such as EVA, ionomer PE, EAA, EMAA, and various modified resins may be used.

  In addition, in order to improve the bonding adhesion between the films to be laminated, corona discharge treatment is applied to the surface to be bonded to one or both of the layers to be laminated prior to (or simultaneously with) lamination. Surface treatment by ozone treatment, anchor coating agent application, etc. may be performed.

(C) Multiple bag 1 according to the second embodiment:
Next, features of the multiple bag 1 according to the second embodiment will be described. In the multiple bag 1 according to the second embodiment, at least the outer film 3 of the multiple film 2 consisting of the outer film 3 and the inner film 4 constituting the multiple bag 1 is an intermediate composed of a mixed resin of cyclic olefin resin and polyolefin resin. It is a multi-layer configuration having layers 32, 42 (see FIGS. 8 and 9). By forming the intermediate layers 32 and 42 made of such mixed resin, the intermediate layers 32 and 42 become easily tearable resin layers, and the back seal portion 6 in which four films (two multiple films 2) are gathered is easily made. It can be torn. Hereinafter, the case where the structure of the multiple film 2 is the tube-like film 21 and the case of the blocking adhesive film 22 will be separately described.

(1) Configuration of Multiplexed Film 2 (Tube-like Film 21):
The tube-shaped film 21 is a facing two film in which both ends of the tubular film flat and formed into two sheets are closed in a bag shape. The tube-like film 21 which is the multiple film 2 is a film in which both side edges of the outer film 3 and the inner film 4 are continuous with each other as shown in FIGS. 3 and 4. Are integrated, and the outer film 3 and the inner film 4 are made of a common resin.

  FIG. 8 is a cross-sectional view showing the layer structure in the case where the outer film 3 and the inner film 4 are three layers in the tube-like film 21. As shown in FIG. In FIG. 8, 3 indicates an outer film, 4 indicates an inner film, 31 and 41 indicate inner layers, 32 and 42 indicate intermediate layers, 33 and 43 indicate outer layers, and C indicates a gap.

  As shown in FIG. 8, in the present embodiment, when the multiple film 2 is a tube-like film 21, both the outer film 3 and the inner film 4 are a mixture of cyclic olefin resin and polyolefin resin. It becomes a multilayer structure which has the intermediate | middle layers 32 and 42 which consist of resin. By interposing a layer composed of a mixed resin of such cyclic polyolefin resin and polyolefin resin as the intermediate layers 32, 42, the intermediate layers 32, 42 become an easy tear resin layer, and the easy opening property (easy tearability) of the multiple film is obtained. improves.

  As shown in an example in FIG. 8, when the outer film 3 and the inner film 4 are multilayers, the outer film 3 and the inner film 4 can be seen from the clearance C formed between the outer film 3 and the inner film 4. From the outside of the multiple bag 1 to the inside of the multiple bag 1 in a symmetrical relationship, the outer / outer layer 33 / intermediate layer 32 / inner layer 31 of the multiple bag 1 (the above is a layer of the outer film 3) / gap C / inner layer 41 / The intermediate layer 42 / the outer layer 43 (the above is the layer of the inner film 4) / the inner side of the multiple bag 1. And when forming the back seal part 6 and the horizontal seal part 7, the layer applicable to the outer layers 33 and 43 will be piled up, will be directly contacted and welded.

  Preferably, the layers corresponding to the outer layers 33 and 43 in FIG. 8 have heat sealability as the resin constituting the tube-like film 21 and as the resin constituting the layers other than the intermediate layers 32 and 42, For example, polyolefin resins can be mentioned. Specifically, high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE), linear (linear) low density polyethylene (LLDPE), straight Linear very low density polyethylene (VLDPE), also copolymers of vinyl compounds copolymerizable with ethylene, such as ethylene-vinyl acetate copolymer (EVA), ionomers, ethylene-acrylic acid or ethylene-acrylic acid Ester copolymer, ethylene methacrylic acid or methacrylic acid ester copolymer, ethylene An acid-modified resin in which a polyethylene-based resin such as a propylene copolymer, a polypropylene-based resin, or a polyolefin-based resin such as polyethylene or polypropylene is modified with acrylic acid, methacrylic acid, maleic anhydride, fumaric acid, or other unsaturated carboxylic acids Polyolefin resin, such as polyolefin resin, is mentioned. One of these resins may be used alone, or two or more thereof may be used in combination.

  Among these resins, it is preferable to use low density polyethylene (LDPE) which is excellent in heat sealability etc. Among low density polyethylenes, it has pinhole resistance and is tough and strong, so it has mechanical strength etc. It is particularly preferred to use linear low density polyethylene (LLDPE) which is also excellent.

  Physical properties, mechanical strength, heat seal strength and the like when using linear low density polyethylene (LLDPE) are adjusted by the number of carbons of the α-olefin to be copolymerized. Generally, α-olefins having 3 to 13 carbon atoms, preferably 4 to 8 carbon atoms, such as butene-1, octene-1, hexene-1, 4-methylpentene-1, hexene-1 and the like are preferably used. Be

The density of the low density polyethylene (including linear low density polyethylene) is preferably 0.870 to 0.935 g / cm ³ . Various properties such as heat sealability are maintained by using the low density polyethylene in the density range. The density of the low density polyethylene is particularly preferably 0.880 to 0.920 g / cm ³ . The melt flow rate (MFR) at 190 ° C. is preferably 0.1 to 30.0 g / 10 min, and particularly preferably 0.5 to 4.0 g / 10 min.

  Further, in FIG. 8, as a resin constituting a layer corresponding to the inner layers 31 and 41, polyolefins such as the above-mentioned polyethylene resin, polypropylene resin and the like in order to impart pinhole resistance and mechanical characteristics to the multilayer film 2 In addition to the resin, it is possible to use polyamide resin (nylon), polyester resin (PET, PBT), ethylene-vinyl alcohol copolymer, and the like.

  Since cyclic polyolefin resin which constitutes mixed resin used as middle class 32 and 42 is in common with cyclic polyolefin resin explained by the above (B) (1) grade, explanation is omitted.

  In the mixed resin, as the resin used in combination with the cyclic polyolefin resin, it is possible to use a polyolefin resin such as the above-mentioned polyethylene resin or polypropylene resin. Among these, polyethylene resins are preferable, low density polyethylene (LDPE) is more preferable, and linear low density polyethylene (LLDPE) is particularly preferable.

  The content of the cyclic polyolefin resin in the mixed resin is preferably 3 to 99% by mass with respect to the entire mixed resin (refers to the total of the cyclic polyolefin resin and the resin used in combination with the cyclic polyolefin resin). By setting the content of the cyclic polyolefin resin in such a range, the easy tearability is favorably implemented. The content of the cyclic polyolefin resin is more preferably 60 to 90% by mass, particularly preferably 60 to 80% by mass, with respect to the entire mixed resin.

  When the outer film 3 and the inner film 4 have the three-layer structure shown in FIG. 8, the outer film 3 is a layer made of linear low density polyethylene (linear low density polyethylene) in order from the outer side of the multiple bag 1 Layer) / layer of mixed resin of cyclic polyolefin resin and polyolefin resin (mixed resin layer) / layer of polyolefin resin (polyolefin resin layer), the inner film is the outer side of the multiple bag 1 (the gap C described above) It is preferable to set it as a polyolefin resin layer / mixed resin layer / linear low density polyethylene layer in order from the above. By making the outer film and the inner film into such a structure, it is possible to impart easy openability (easy tearability) while maintaining heat sealability, pinhole resistance and the like.

  In order to produce the tube-shaped film 21 which is the multiple film 2, for example, it is preferable to obtain it by the inflation film method. The inflation film has a tubular shape (tubular shape) in advance, can be used as manufactured, and has the merit that the film does not have to be cylindrical in a later step and no seam is generated. In addition, the inflation film can easily produce a relatively thick film as well as a thin film.

  As a general inflation film method, for example, a molten resin extruded in the form of a tube from an extruder through a die is vertically pulled up, and the molten resin is expanded by air supplied in the process of being pulled up vertically, and the tube is expanded. By rolling the film into a flat film while air cooling it and winding it around a winding device, it is possible to obtain a roll in which the tubular film 21 is wound flat.

  In the case where the multiple film 2 is a tube-like film 21, the layers (inner layers 31 and 41 in FIG. 8 described above) which do not appear on the outer side of the outer film 3 and the inner film 4 but contact each other mutually block. It is preferable to adhere. Here, "blocking and adhering to each other" means that the films in contact with each other are not completely integrated by bonding them with other media such as an adhesive or by heat fusion, but are in contact with each other. These films are pseudo-bonded to each other in a flexible state. Blocking adhesion may occur over the entire surface of the film or may partially occur on a part of the film. By blocking adhesion, the outer film 3 and the inner film 4 are integrated at the time of bag making or the like, and the handleability is improved.

  In order to block and bond the tubular film 21, for example, the tubular film made of a polyolefin based film formed by the above-mentioned inflation film method is pressed by a folding nip roll or the like to push out air between the superposed films. It can manufacture simply by winding up as a flat two-layer film.

(2) Configuration of Multiple Film 2 (Blocking Adhesive Film 22):
Next, the case where the multiple film 2 is used as the blocking adhesive film 22 will be described. As the multi-layer film 2, it is possible to use a configuration (blocking adhesive film) in which the separately independent outer film 3 and the inner film 4 are bonded by blocking.

  Here, the “blocking adhesion” is as described above, and the films in contact with each other are not completely integrated by bonding them with another medium such as an adhesive or heat fusion, and are not films. It indicates that the films in contact with each other are in a pseudo-adhesive state and in a flexible state. Blocking adhesion may occur over the entire surface of the film or may partially occur on a part of the film. By blocking adhesion, the outer film 3 and the inner film 4 are integrated at the time of bag making or the like, and the handleability is improved.

  In the present embodiment, the blocking adhesive film 22 to be the multiple film 2 is a layer (hereinafter referred to as a “blocking adhesive layer”) composed of the outer film 3 (inner layer 31 in FIG. 9) and the inner film 4 that are blocking bonded. In some cases, the intermediate layer 32 and the outer layer 33, which are made of a mixed resin of a cyclic polyolefin resin and a polyolefin resin, are laminated as the outer film 3.

  FIG. 9 is a cross-sectional view showing the layer configuration in the case of forming three layers of the outer film 3 in the blocking adhesive film 22. In FIG. 9, 3 is an outer film, 4 is an inner film, 31 is an inner layer, 32 is an intermediate layer, 33 is an outer layer, and B is a surface on which blocking adhesion is performed. As shown in FIG. 9, in the blocking adhesive film 22, the surface of the inner film 4 in contact with (the inner layer 31 of) the outer film 3 and the surface of the inner layer 31 of the outer film 3 in contact with the inner film 4 block It will adhere. Moreover, in the blocking adhesive film 22, when the back | inner seal | sticker part 6 and the horizontal seal | sticker part 7 are comprised, the inner film 4 will be piled up and will be directly contacted and welded.

  The content and the like of the cyclic polyolefin resin and polyolefin resin constituting the intermediate layer 32 composed of the mixed resin of the cyclic polyolefin resin and the polyolefin resin in the outer film 3 and the cyclic polyolefin resin in the mixed resin are described above (1) tube shape The content is the same as the cyclic polyolefin resin and the polyolefin resin constituting the film, the content of the cyclic polyolefin resin in the mixed resin, and the like (also described in the above (B)), and thus the description is omitted.

  As resin (The inner film 4 and the inner layer 31 in the outer film 3) which comprises the blocking adhesive layer in the blocking adhesive film 22, the polyolefin resin mentioned by above-mentioned (1) can be used, for example. Among such polyolefin resins, polyethylene resins are preferably used, low density polyethylene (LDPE) is more preferably used, and linear low density polyethylene (LLDPE) is particularly preferably used.

  Moreover, as resin which comprises the outer layer 33 in the outer side film 3, in addition to polyolefin resin, such as a polyethylene-type resin and the polypropylene-type resin which were mentioned above, in order to provide pinhole resistance and mechanical characteristics to the multilayer film 2, polyamide. It is possible to use a base resin (nylon), a polyester resin (PET, PBT), an ethylene-vinyl alcohol copolymer, and the like.

  When using the blocking adhesive film 22 as the outer film 3 having the three-layer structure shown in FIG. 9, the outer film 3 is a layer made of a polyolefin resin (polyolefin resin layer) in order from the outside of the multiple bag 1 / Layer consisting of mixed resin of cyclic polyolefin resin and polyolefin resin (mixed resin layer) / Layer consisting of linear low density polyethylene (linear low density polyethylene layer), inner film is linear low density polyethylene layer It is preferable to By making the outer film 3 and the inner film 4 in such a configuration, easy openability (easy tearability) can be imparted while maintaining heat sealability, pinhole resistance, and the like.

  The blocking adhesive layer to be adhered is, for example, folded and stacked a tubular film extruded when producing an inflation film by a single layer extrusion inflation method, and newly provided after a pulling nip roll or a pulling nip roll. It can be manufactured by, for example, a method of press-contacting on-line with a pressure bonding roll, blocking the inner surfaces of the film, and winding it in a roll shape. As another method, a film which is separately wound without blocking is extracted off-line in an off-line manner, layers to be blocked are superposed and aligned, and thermocompression bonding is carried out through blocking between heated pressure rolls, etc. However, in terms of simplicity of operation, cost and the like, it is preferable to use the above-described method of compression bonding and blockinking simultaneously with the above-described inflation molding.

  The ease of blocking adhesion of the film to be superposed is appropriately changed depending on the type and density of the resin (polyolefin resin etc.) to be used, and the type and amount of additives such as lubricant and antiblocking agent. Generally, the higher the density of the resin, the more difficult the blocking the greater the amount of additive. Also, in order to adjust the blocking adhesive strength of the film formed and folded by the inflation method, the film before the folded tube-like film passes rolls such as a nip roll, a pressure roll, an embossing roll, a heating roll, etc. May be heated using a heating means such as a far infrared lamp or a nichrome wire heater.

  The adhesive strength of the two layers for blocking adhesion should be at least a level that does not cause unintended peeling of blocking in the film laminating step, slitting step, bag making or automatic filling and bag making step and does not impair the mechanical suitability. . The same applies to the case where the inner layers 31 and 41 are adhered to each other in the above (1).

  In order to laminate the blocking adhesive layer and the other layers, for example, a dry lamination method of adhering through a predetermined adhesive, a solventless lamination method, a hot melt lamination method, an extrusion lamination method or the like is used. For example, in the case of the dry lamination method, although it is general to use a one-component or two-component polyurethane adhesive, the invention is not limited thereto, depending on the type of resin constituting the layer to be laminated, etc. The type of adhesive may be selected appropriately.

  In addition, in order to improve the bonding adhesion between the films to be laminated, corona discharge treatment is applied to the surface to be bonded to one or both of the layers to be laminated prior to (or simultaneously with) lamination. Surface treatment by ozone treatment, anchor coating agent application, etc. may be performed.

  In addition, the layer which consists of mixed resin of cyclic | annular polyolefin resin and polyolefin resin does not have a problem also as layers other than a middle layer in a multilayer outer film, It is the same as that of a tube-like film also about this.

(3) About the tear start part 51:
Next, the tear start portion 51 formed in the multiple bag according to the present embodiment will be described. The multiple bag 1 according to the second embodiment of the present invention, as shown in FIG. 1 and FIG. 2, tears against the palmar part 5 in which both ends of the multiple film 2 are overlapped such that the inner films 4 face each other. The start part 51 is formed. The tear start portion 51 is formed to be opened substantially parallel to the lateral seal portion 7, and for example, if formed so as to be substantially parallel to the lateral seal portion 7, the user can open the lateral seal portion 7. In contrast, it becomes easy to open almost parallel.

  The tear start part 51 formed in the joint part 5 weakens the initial tear strength and improves the easy opening property. The tear start part 51 can be made into arbitrary shapes, such as a slit (break), a V notch, an I notch, a perforation, a microporous aggregate, and the like.

  The tear start portion 51 is preferably formed to extend from the outer edge 52 of the combined palm portion to at least the back seal portion 6 as shown in FIGS. 1 and 2. When the tear start portion 51 reaches the back seal portion 6, the tearing-out can be smoothly performed at the time of opening, and the back seal portion 6 in which the multiple films 2 are collected can be easily torn. It becomes a multiple bag 1 with excellent sex. The length of the tear start portion 51 is not particularly limited, but may be approximately 5 to 20 mm.

  In the case where a plurality of narrow linear back seal portions 6 are formed, the tear start portion 51 may be as shown in FIG. FIG. 7 is a front view showing another aspect of the multiple bag 1. FIG. 7 shows an aspect in which two back seal parts 6 are formed in a narrow line shape with respect to the aikomo part 5. Thus, in the case where a plurality of narrow linear back seal portions 6 are formed, the tear start portion 51 is formed at least on the outer edge 52 side of the combined palm portion among the plurality of narrow linear back seal portions 6 It is formed to reach the back seal portion 61. In the present invention, the narrow linear back seal parts 6 and 61 indicate the substantially straight back seal parts 6 each having a width of about 2 to 10 mm by heat sealing (welding). . In addition, the number of the plurality of back seal parts 6, 61 may be approximately 2 to 5.

(D) Manufacturing method of multiple bag 1 (first embodiment (first invention), second embodiment (common to second invention)):
The multiple bag 1 according to the present invention having the configuration shown in FIG. 1 using the multiple film 2 can be manufactured using, for example, a vertical pillow type bag making machine or the like. To illustrate an example, the multiple film 2 is supplied from a roll wound with the multiple film 2, and the supplied multiple film 2 is formed into a tubular shape by a former after passing through the guide roll group, and a back seal bar After the back seal portion 6 is formed and filled with the filling material, the multiple seal bag 1 shown in FIG. 1 and the like can be easily obtained by simultaneously forming the cross seal portion 7 with the horizontal seal bar and cutting it. .

(E) Thickness of Multiplexed Film Constituting Multiplexed Bag (First Embodiment (First Invention), Second Embodiment (Second Invention))
In the multiple bag 1 according to the present invention, the thickness of the outer film 3 and the inner film 4 in the multiple film 2 is preferably 30 to 150 μm. Further, in the case of the three-layer configuration as shown in FIGS. 8 and 9, the inner layers 31, 41 and the outer layers 33, 43 preferably have a thickness of approximately 10 to 70 μm. It is preferable to set it as 7-30 micrometers in general.

(F) Effects of the present invention:
In the multiple bag 1 according to the first embodiment of the present invention described above, the tear start part 51 formed in the double palm portion 5 of the multiple bag 1 composed of the multiple film 2 including the outer film 3 and the inner film 4 Since it is formed to reach at least the back seal part 6 from the outer edge 52 of the part, it is possible to smoothly carry out the tearing at the time of opening, and including the back seal part 6 in which the four films are gathered It becomes the multiple bag 1 excellent in easy openability which can tear 2 easily.

  In the multiple bag 1 according to the second embodiment of the present invention described above, at least the outer film 3 of the multiple bag 1 formed of the multiple film 2 including the outer film 3 and the inner film 4 is a cyclic olefin resin and polyolefin. Since the intermediate layers 32 and 42 made of a mixed resin with a base resin are included, the intermediate layers 32 and 42 become easy-to-tear resin layers to facilitate tearing from the tear start portion 51 formed on the palm 5. It becomes the multiple bag 1 excellent in easy-open property which can tear the multiple film 2 easily including the back seal part 6 which the sheet film gathered.

  The above-mentioned multiple bag 1 can be used, for example, for transportation, storage, sale, etc. of materials such as liquids, semi-fluids, powders, solids, and pastes used for business use and industrial use, food etc. Especially, bags used for transporting liquid foods such as juice, mineral water, soft drinks, coffee, black tea, green tea, seasonings, vegetable oil, mayonnaise, sauce, ketchup, juice, etc. It is useful as a multiple bag 1 for back-in-box. In addition, although the example made into a bag was shown in the state which filled the contents in the above-mentioned manufacturing method, it is a problem even if it is used in the state where the filling is not filled yet, and the seal part etc. are not formed. There is no.

  Also, when used in a back-in box, the multiple bag 1 filled with contents is transferred from the cardboard box housed in to the predetermined container (bucket etc.) as the multiple bag 1 and placed in the predetermined container There is also a case where the contents are taken out and used by opening it. When opening the multiple bag 1, it is unnecessary in the case where the entire area including the opposite face as well as the side on which the combined palm 5 is formed is torn and the unnecessary part torn from the multiple bag 1 is removed. Department becomes garbage and processing becomes troublesome. Therefore, it is preferable that the entire circumference is not torn and removed but only the surface on which the palm 5 is formed to be torn open so that the contents can be removed without removing the torn portion from the multiple bag 1 .

(G) Modification of Embodiment:
In addition, the aspect demonstrated above shows one aspect of this invention, Comprising: This invention is not limited to above-described embodiment, It comprises the structure of this invention and can achieve the objective and the effect. It goes without saying that modifications and improvements within the scope are included in the contents of the present invention. In addition, the specific structure, shape, and the like in practicing the present invention have no problem as other structures, shapes, and the like as long as the objects and effects of the present invention can be achieved. The present invention is not limited to the above-described embodiments, and modifications and improvements as long as the object of the present invention can be achieved are included in the present invention.

  For example, in the embodiment described above, the tube-like film 21 and the blocking adhesive film 22 have been described as an example of the configuration of the multiple film 2, but the multiple film is not limited thereto. Multiple films of any configuration consisting of 4 can be used.

  In addition, although the structure which made the outer film 3 and the inner film 4 into 3 layers is shown in FIG. 8 when using a tube-like film, it is not restrict | limited to this structure, The outer film 3 and the inner film 4 are shown. For example, another layer may be formed between the intermediate layers 32 and 42 and the outer layers 33 and 43 and between the intermediate layers 32 and 42 and the inner layers 31 and 41. As resin which comprises this other layer, resin etc. which comprise the above-mentioned inner layers 31 and 41 and middle layers 32 and 42 in tube-like film ((B) (1), (C) (1)) are used. can do.

  Moreover, although the structure which made the outer film 3 3 layers in the case where the blocking adhesive film 22 is used is shown in FIG. 9, it is not restrict | limited to this structure, 4 layers or more of outer film 3 layer structures are shown. For example, another layer may be formed between the intermediate layer 32 and the outer layer 33 and between the intermediate layer 32 and the inner layer 31. As resin which comprises this other layer, resin etc. which comprise the above-mentioned outer layer 33 in the blocking adhesive film ((B) (2), (C) (2)), and the intermediate layer 32 can be used.

  The outer film 3 and the inner film 4 in the tubular film 21 may be a single layer or two layers. In the case of using a single layer, the resin constituting the outer layers 33 and 43 in the tube-shaped film 21 ((B) (1), (C) (1)) of the three-layer structure shown in FIG. Good. In the case of two layers, the resin or the like constituting the outer layers 33 and 43 may be used for the layer appearing on the outer side, and the inner layer described above for the layer appearing on the inner side (layer facing the gap C). The resin etc. which comprise 31,41 and the intermediate | middle layers 32 and 42 can be used.

  The outer film 3 in the blocking adhesive film 22 may be a single layer or two layers. In the case of using a single layer, the resin or the like constituting the above-mentioned inner layer 31 in the blocking adhesive film 22 ((B) (2), (C) (2)) of the three-layer structure shown in FIG. . Moreover, when it is set as 2 layers, resin etc. which comprise the above-mentioned outer layer 33 and the intermediate | middle layer 32 can be used about the layer which appears on the outer side, resin etc. which comprise the above-mentioned inner layer 31 about the layer to block-adhere Can be used.

  In the present invention, for example, the “intermediate layer” such as an intermediate layer comprising a mixed resin of a cyclic polyolefin resin and a polyolefin resin refers to the outer layer and the inner layer of the film (in the case of three layers, see FIG. 8 and FIG. Layers other than the middle layer in the case of a three-layer structure, layers other than the outermost layer and the innermost layer in the four or more layer structure are also included in the “middle layer”.

  In the present invention, the “tearing start portion 51 for opening substantially parallel to the horizontal seal portion 7” is formed in the joint palm portion 5 for opening in the lateral direction (longitudinal direction of the horizontal seal portion 7). In order to open the longitudinal direction (longitudinal direction of the back seal portion 6) or the like, for example, after forming the tear start portion 51 in the combined palm portion 5 The tear start portion not shown may be separately formed.

In addition, in the range which does not impair the effect of this invention in the above-mentioned resin (resin material) which comprises the multiple film 2, for example, a plasticizer, an antistatic agent, an antioxidant, a lubricant, an antifogging agent, an ultraviolet absorber Various additives generally used in the field of resin materials may be added, such as heat stabilizers, nucleating agents, mold release agents, coloring agents and neutralizing agents.
In addition, the specific structure, shape, and the like at the time of implementation of the present invention may be other structures and the like as long as the object of the present invention can be achieved.

  The present invention can be advantageously used for packaging and transportation of materials, foods and the like, and has high industrial applicability.

DESCRIPTION OF SYMBOLS 1 ...... Multi-layer bag 2 ...... Multi-layer film 21 ...... Tubular film 22 ...... Blocking adhesive film 3 ...... Outer film 4 ...... inner film 31, 41 ...... inner layer 32, 42 ...... middle layer 33, 43 ...... Outer layer 5 ...... chasing portion 51 ...... tearing start portion 52 ...... outer rim 6 ...... back seal portion 61 ...... back seal portion 7 formed on outer edge side of chasing portion 7 ...... horizontal seal portion B ...... blocking Bonded surface C ...... Gap

Claims (9)

A multiple bag consisting of multiple films consisting of an outer film and an inner film, wherein
An overlapping palm portion is formed by overlapping the both ends of the multiple film so that the inner films face each other,
While forming a back seal portion in which all outer films and inner films to be overlapped are welded and integrated with a predetermined width to the arbor ,
A lateral seal is formed by welding with a predetermined width in the vicinity of both end edges on the side orthogonal to the back seal, whereby a multiple bag filled and sealed with contents is formed.
Wherein the rafter part having said to open to tear substantially parallel to the transverse seal portion, the tear initiation portion which is substantially formed parallel to the lateral sealing portion,
The multi bag according to claim 1, wherein the tear initiation portion is formed to reach at least the back seal portion from an outer edge of the palm portion. The back seal portion is formed in a plurality of narrow lines with respect to the palm portion,
The multiple bag according to claim 1, wherein the tear start portion is formed to reach at least the back seal portion formed on the outer edge side of the combined palm portion among the plurality of back seal portions.   The multi-layer film according to claim 1 or 2, wherein the multi-layer film is a flat film of tube-shaped films and formed of two sheets, and the two ends of the multi-layer film are closed and closed in a bag shape. bag. The outer film is composed of a layer made of linear low density polyethylene, a resin layer made of easily tearable resin, and a resin layer made of polyolefin resin in this order from the outside of the multi-layer bag,
4. The multiple bag according to claim 3, wherein the inner film is composed of a layer made of a polyolefin resin / a tearable resin layer / a layer made of linear low density polyethylene in order from the outside of the multiple bag.   5. The multiple bag according to claim 4, wherein the easily tearable resin layer is made of a mixed resin containing 3 to 99% by mass of cyclic polyolefin based on the entire easy tear resin layer. A multiple bag consisting of multiple films consisting of an outer film and an inner film, wherein
An overlapping palm portion is formed by overlapping the both ends of the multiple film so that the inner films face each other,
While forming a back seal portion in which all outer films and inner films to be overlapped are welded and integrated with a predetermined width to the arbor,
A lateral seal is formed by welding with a predetermined width in the vicinity of both end edges on the side orthogonal to the back seal, whereby a multiple bag filled and sealed with contents is formed.
The combined palm portion has a tear start portion formed substantially parallel to the transverse seal portion for opening so as to tear substantially parallel to the transverse seal portion,
At least the outer film has a multilayer structure having an intermediate layer made of a mixed resin of a cyclic polyolefin resin and a polyolefin resin. The multi-layer film is a flat film of tube-shaped films and is formed of two stacked sheets of facing two films closed at both ends in a bag shape.
7. The multiple bag of claim 6, wherein the outer film and the inner film comprise the intermediate layer.   The multiple adhesive film according to claim 6, wherein the multi-layer film is a blocking adhesive film in which a surface of the inner film in contact with the outer film and a surface of the outer film in contact with the inner film are blocked and adhered. bag.   The multiple bag according to any one of claims 6 to 8, wherein the mixed resin contains the cyclic polyolefin resin in an amount of 3 to 99% by mass based on the entire mixed resin.

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