JP2019142598A - bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bag which can be used as a back-in box or the like and has excellent ease of opening. According to the present invention, a tear starting portion 51 formed in a gassho portion 5 of a multilayer bag 1 composed of a multilayer film 2 composed of an outer film 3 and an inner film is formed at least from an outer edge 52 of the gassho portion to a back seal portion 6. Since it is formed so as to reach up to, the multi-layer bag 1 having excellent easy-opening property can easily tear the multi-layer film 2 including the back seal portion 6 in which four films are gathered. Further, at least the outer film 3 has an intermediate layer made of a mixed resin of a cyclic olefin resin and a polyolefin resin, so that the multilayer film 2 can be easily torn, and the multilayer bag 1 having excellent openability can be easily torn. Become. [Selection diagram] Fig. 1

Description

  The present invention relates to a bag. More specifically, the present invention relates to a bag that can be used for a so-called back-in box or the like and can wrap or carry a predetermined content such as a material or food.

  Conventionally, materials such as liquids, semi-fluids, powders, solids, pastes, foods, etc. used for business use have been packed in metal containers for transportation, storage, and sales. On the other hand, a metal container has problems such as a bulky container after use, difficulty in taking out contents, difficulty in processing the container after use, and heavy container weight.

  In recent years, a so-called bag-in-box packaging method in which such contents are stored in a cardboard box, pallet, or the like in a state in which the contents are filled in a bag made of a synthetic resin film has been widely put into practical use. In such a bag-in-box, it is required that the bag film has high mechanical strength, and a film obtained by laminating a layer having heat-fusibility on a high-strength film such as nylon or polyester is used. In addition, attempts have been made to laminate films other than the above or to increase the thickness in order to further increase the mechanical strength. However, in reality, this cannot be solved only by increasing the thickness of the film.

  In view of this, there has been proposed a multiple bag in which the two films forming the bag are not completely laminated, and there is a degree of freedom of mutual movement (see, for example, Patent Document 1). This multiple bag (also called double bag) consists of an outer film that appears on the outside and an inner film that contacts the contents, and can prevent damage to other films even if pinholes occur in one film. . In addition, even against bending stress, a certain amount of slip can be generated between the inner film supporting the contents and the outer film supporting the multiple bag in contact with the cardboard box or the like. Is absorbed and an excessive bending stress is prevented from being applied, and the occurrence of pinholes in the film forming the bag or the rupture of the bag is prevented.

Japanese Patent No. 4490045

  When taking out the filled contents, the multiple bag is often torn from the back seal part and opened, but for example, when the back seal part is formed at the joint part as a pasting at the joint part It is necessary to tear the four seals collected at the joint part, and there is a problem that the easy-opening property is not good, including the freedom to move the outer film and the inner film relative to each other. It was rare.

  This invention is made | formed in view of the said subject, For example, it can be used for a back-in box etc., It is providing the bag excellent in easy-opening property.

  In order to solve the above-mentioned problem, the bag according to the first invention of the present invention has a palm portion formed by overlapping both ends of the film so that the films face each other, and with a predetermined width in the palm portion, By forming a back seal part in which the films to be superimposed are integrated to form a back seal part, and a lateral seal part in which the vicinity of both end edges on the side orthogonal to the back seal part is welded with a predetermined width is formed. A bag is formed which is filled and sealed with the contents, and the tearing portion is formed substantially parallel to the lateral seal portion for opening the joint portion so as to tear substantially parallel to the lateral seal portion. The tear start portion is formed so as to reach at least the back seal portion from an outer edge of the palm portion.

  The bag according to a first aspect of the present invention is the bag according to the first aspect, wherein the back seal portion is formed in a plurality of narrow lines with respect to the palm portion, and the tear start portion is formed of the plurality of back seal portions. Of these, it is formed so as to reach at least the back seal portion formed on the outer edge side of the palm portion.

  In the multiple bag according to the second aspect of the present invention, a palm portion is formed by overlapping both ends of the film so that the films face each other, and the films to be overlapped with each other at a predetermined width are welded to the palm portion. A bag in which the contents are filled and sealed by forming an integrated back seal part and forming a horizontal seal part welded with a predetermined width near both end edges on the side orthogonal to the back seal part And the tearing portion has a tear start portion formed substantially parallel to the lateral seal portion for opening so as to tear substantially parallel to the lateral seal portion, and at least the The film has a multilayer structure having an intermediate layer made of a mixed resin of a cyclic polyolefin resin and a polyolefin-based resin.

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

  Since the bag according to the first aspect of the present invention is formed so that the tear start portion formed at the palm portion of the bag reaches at least the back seal portion from the outer edge of the palm portion, the multiple film can be easily torn. A bag that is easy to open.

  Further, the bag according to the second invention of the present invention has an intermediate layer made of a mixed resin of a cyclic olefin resin and a polyolefin resin, so that the film can be easily torn and easily opened. An excellent bag.

It is the perspective view which showed the multiple bag based on this invention. It is the front view which showed the multiple bag which concerns on this invention. It is the schematic which showed the state which curved the multiple film (tubular film) in the cylinder shape, and overlapped and formed the palm part. It is an enlarged view of the back seal part at the time of using a tubular film. It is the schematic which showed the state which curved the multilayer film (blocking adhesive film), and overlapped and formed the palm part. It is an enlarged view of the 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 making an inner film and an outer film into 3 layers. In a blocking adhesive film, it is sectional drawing which showed the layer structure at the time of making an outer film into 3 layers.

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

(A) Configuration of the multiplex bag 1 (common to the first embodiment (first invention) and the second embodiment (second invention)):
Hereinafter, the multiple bag 1 according to the present invention will be described. FIG. 1 is a perspective view showing a multiplex bag 1 according to the present invention, FIG. 2 is a front view showing the multiplex bag 1 according to the present invention, and FIG. 3 shows a multiplex film 2 (tubular film 21) in a cylindrical shape. FIG. 4 is an enlarged view of the back seal portion 6 when the tube-shaped 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 palm portion, 51 is a tear start portion, 52 is an outer edge of the palm portion, 6 is a back seal portion, and 61 is a palm. A back seal part formed on the outer edge 52 side of the part, and 7 a horizontal seal part.

  The multiple bag 1 shown in FIGS. 1 and 2 is constituted by a multiple fill 2 composed of an outer film 3 and an inner film 4. As for the outer film 3 and the inner film 4, when the bag is made as the multiple bag 1, the film that appears outside the multiple bag 1 (in contact with a cardboard box or the like not shown) is the inner film of the outer film 3 or the multiple bag 1. The film appearing at (in contact with the contents not shown) is referred to as the inner film 4.

  As shown in FIG. 3, the palm portion 5 constituting the multiplex bag 1 is formed by bending the multiplex film 2 into a cylindrical shape and overlapping the both ends of the multiplex film 2 so that the inner films 4 face each other. .

  The multiplex bag 1 is filled with a predetermined content when used, and the back seal portion 6 and the lateral seal portion 7 are formed, whereby the content is filled and sealed. As shown in FIG. 1 and FIG. 2, the back seal portion 6 is welded in a band shape with a predetermined width (generally about 2 to 20 mm; the same shall apply hereinafter) with respect to the palm portion 5 (that is, heat sealing or heat sealing). The same shall apply hereinafter). Further, the lateral seal portion 7 is formed by welding the vicinity of both end edges on the side orthogonal to the back seal portion 6 with a predetermined width (approximately 2 to 20 mm; the same applies hereinafter) in a band shape. In addition, you may make it the horizontal seal | sticker part 7 consist of a some narrow width | variety seal part.

  Both the back seal portion 6 and the lateral seal portion 7 are formed by sandwiching the inner films 4 of the multiple film 2 in a flat state and sandwiching them with a seal bar having a predetermined width (not shown) from the outside. FIG. 4 shows an enlarged view of the back seal portion 6. In addition to the inner films 4 that are in contact with each other, the outer film 3 as well as all the films that are superposed (total of two outer films and two inner films) are shown. 4) are welded and integrated. This also applies to the lateral seal portion 7.

  3 and 4 show an embodiment in which the tubular film 21 described later in (B) (1) and (C) (1) is used as the configuration of the multiple film 2. 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, when the blocking adhesive film 22 described in (B) (2) and (C) (2) described later is used as the configuration of the multiple film 2, the following is obtained. FIG. 5 is a schematic view showing a state in which the multiple film 2 (blocking adhesive film 22) is bent into a cylindrical shape and overlapped to form the palm portion 5, and FIG. 6 shows a case where the blocking adhesive film 22 is used. It is an enlarged view of the back seal part 6 in FIG. Thus, unlike the tubular film 21, the blocking adhesive film 22 is not integrated with the outer film 3 and the inner film 4, 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 1:
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 torn against the palm portion 5 in which both ends of the multiple film 2 are overlapped so that the inner films 4 face each other. A start portion 51 is formed. The tear start portion 51 is formed to open substantially parallel to the lateral seal portion 7. For example, if the tear start portion 51 is formed so as to be substantially parallel to the lateral seal portion 7, the user can contact the lateral seal portion 7. On the other hand, it becomes easy to open it substantially parallel.

  The tear start part 51 formed in the palm part 5 weakens the initial tear strength and improves easy-openability. The tear start portion 51 can have an arbitrary shape such as a slit (cut), a V notch, an I notch, a perforation, or a microporous aggregate.

  As shown in FIGS. 1 and 2, the tear start portion 51 is formed so as to reach at least the back seal portion 6 from the outer edge 52 of the palm portion. Since the tear start portion 51 reaches the back seal portion 6, the tear can be smoothly drawn out at the time of opening, and the back seal portion 6 in which four films (two multiplex films 2) gather can be easily obtained. It becomes the multiple bag 1 excellent in easy-opening property that can be torn. In addition, 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 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 portions 6 are formed in a narrow line shape with respect to the palm portion 5. As described above, when a plurality of narrow line-shaped back seal portions 6 are formed, the tear start portion 51 is formed on the outer edge 52 side of at least the palm portion of the plurality of narrow line-shaped back seal portions 6. It is formed so as to reach the back seal portion 61 made. In addition, in this invention, the narrow line-shaped back seal parts 6 and 61 point out the back seal part 6 formed in the substantially linear form which has a width | variety about 2-10 mm by heat sealing (welding). . Moreover, what is necessary is just to make the number of the some back seal parts 6 and 61 into 2-5 in general.

(1) Configuration of multiple film 2 (tubular film 21):
Next, the multiple film 2 constituting the multiple bag 1 will be described. As for the multiple film 2, the outer film 3 and the inner film 4 are stacked in two layers. For example, the two ends of the cylindrical film that are flattened and stacked in two layers face each other closed in a bag shape 2 It can be set as a sheet of film (tube-shaped film 21). As can be seen from FIG. 3 and FIG. 4, the tubular film 21 that is the multiple film 2 is one in which both side edges of the outer film 3 and the inner film 4 are continuous with each other, and the outer film 3 and the inner film 4. Are integrated. Therefore, 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, the tubular film 21 having a three-layer configuration in which the outer film 3 and the inner film 4 are shared will be described as an example.

  FIG. 8 is a cross-sectional view showing the layer structure of the tubular film 21 when the outer film 3 and the inner film 4 have three layers. In FIG. 8, 3 is an outer film, 4 is an inner film, 31 and 41 are inner layers, 32 and 42 are intermediate layers, 33 and 43 are outer layers, and C is a gap.

  As shown in FIG. 8, when the outer film 3 and the inner film 4 are multilayered, the outer film 3 and the inner film 4 are viewed from a gap C formed between the outer film 3 and the inner film 4. From the outer side of the multiple bag 1 to the inner side of the multiple bag 1, the outer side of the multiple bag 1 / outer layer 33 / intermediate layer 32 / inner layer 31 (the above is the layer of the outer film 3) / gap C / inner layer 41. / Intermediate layer 42 / outer layer 43 (the above is the layer of the inner film 4) / inner side of the multiple bag 1. Then, when the back seal portion 6 and the lateral seal portion 7 are formed, the layers corresponding to the outer layers 33 and 43 are overlapped and welded in direct contact with each other.

  Of the layers described above, the outer layers 33 and 43 that are welded in direct contact with each other when the back seal portion 6 and the lateral seal portion 7 are formed preferably have heat sealability. For example, 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), and copolymers of vinyl compounds copolymerizable with ethylene, such as ethylene-vinyl acetate copolymer (EVA), ionomers, ethylene-acrylic acid or ethylene-acrylic ester copolymers, Polyethylene such as ethylene methacrylic acid or methacrylic acid ester copolymer, ethylene-propylene copolymer Polyolefin resins such as resins, polypropylene resins, and acid-modified polyolefin resins obtained by modifying polyolefin resins such as polyethylene and polypropylene with acrylic acid, methacrylic acid, maleic anhydride, fumaric acid, and other unsaturated carboxylic acids Is mentioned. One of these resins may be used alone, or two or more thereof may be used in combination.

  Of these resins, it is preferable to use low-density polyethylene (LDPE), which has excellent heat-sealing properties, etc. Among low-density polyethylene, it has pinhole resistance, is tough and strong, and has mechanical strength, etc. In particular, it is particularly preferable to use linear low density polyethylene (LLDPE).

  The physical properties, mechanical strength, heat seal strength, and the like when linear low density polyethylene (LLDPE) is used are adjusted by the number of carbon atoms of the α-olefin to be copolymerized. In general, 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, heptene-1, etc. are preferably used. It is done.

  The density of the low density polyethylene (including the linear low density polyethylene) is preferably 0.870 to 0.935 g / cm 3. Various characteristics such as heat sealability are maintained by using low density polyethylene in a range where the density is high. The density of the low density polyethylene is particularly preferably from 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 minutes, and particularly preferably 0.5 to 4.0 g / 10 minutes.

  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 are provided with the above-described polyethylene-based resin and polypropylene-based resin so as to impart pinhole resistance and mechanical properties to the multiple 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 easily tearable resin layers made of easily tearable resin. By using the easy tear resin as the intermediate layers 32 and 42, it is possible to impart further easy opening to the multiple film 2. When the outer film 3 and the inner film 4 have the three-layer configuration shown in FIG. 8, the outer film 3 is a layer made of linear low density polyethylene (linear Density polyethylene layer) / easy tear resin layer / polyolefin resin layer (polyolefin resin layer), inner film 4 is polyolefin resin layer / easy tear resin in order from the outer side of the multiple bag 1 (the aforementioned gap C). Layer / linear low density polyethylene layer is preferred. By setting the outer film 3 and the inner film 4 as such a configuration, easy-openability (easy tearing property) can be imparted while maintaining heat sealability, pinhole resistance, and the like.

  As the resin constituting the easily tearable resin layer, for example, a mixed resin containing a cyclic polyolefin resin may be used. By interposing the layer containing the cyclic polyolefin resin as the intermediate layers 32 and 42, the easy-openability (easy tearing property) of the multiple film 2 is improved.

  The cyclic polyolefin resin is a general term for resins that are polymerized with a cyclic olefin as a polymerization unit, and is described in, for example, JP-A-1-240517, JP-A-3-14882, JP-A-3-122137, and the like. Has been. In the present invention, a ring-opening metathesis polymer obtained by polymerizing a cyclic olefin by a metathesis ring-opening polymerization reaction (also referred to as a cycloolefin polymer (COP)), as well as a cyclic olefin and an α-olefin. So-called cyclic olefin copolymers (also called cycloolefin copolymers (COC)), which are copolymers with (chain olefins), etc., and graft weights modified with unsaturated carboxylic acids or their derivatives Including coalescence and hydrides thereof.

  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. Bicyclo [2.2.1] hept-2- Those having an ene (norbornene) skeleton are preferred.

  Specifically, bicyclo [2.2.1] hept-2-ene and derivatives thereof, tricyclo [4.3.0.12.5] -3-decene and derivatives thereof, and tricyclo [4.4.0. 12.5] -3-undecene and derivatives thereof, tetracyclo [4.4.0.12.5.17.10] -3-dodecene and derivatives thereof, pentacyclo [6.5.1.13.6.02. 7.09.13] -4-pentadecene and its derivatives, pentacyclo [7.4.0.12.5.19.12.2.08.13] -3-pentadecene and its derivatives, pentacyclo [6.5.1. 13.6.0.2.7.09.13] -4,10-pentadecadiene and its derivatives, pentacyclo [8.4.0.12.5.19.12.08.13] -3-hexadecene and its derivatives Derivatives and the like, But it is not limited to these.

  In addition, the cyclic olefin has, for example, a carboxyl group, an acid anhydride group such as a carboxylic acid anhydride, an epoxy group, an amino group, an amide group, an ester group, a hydroxyl group, a sulfo group, a phosphono group, a phosphino group, etc. May have a polar group. Moreover, (meth) acrylic acid, maleic acid, maleic anhydride, itaconic anhydride, glycidyl (meth) acrylate, alkyl (meth) acrylate (for example, carbon number 1-10) ester, alkyl maleate (for example, carbon number) 1-10) ester, (meth) acrylamide, (meth) acrylic acid-2-hydroxyethyl and the like can be mentioned, preferably carboxyl group, acid anhydride group, epoxy group, amino group, amide group, ester group And 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 α-olefin copolymerized with the cyclic olefin as the cyclic olefin copolymer, for example, ethylene and an α-olefin having 3 to 20 carbon atoms can be used. Specifically, ethylene, propylene, 1- Examples include butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, and ethylene is widely used.

  When a polyethylene resin is used as a resin (described later) to be combined with a cyclic polyolefin resin, it is preferable to use a cyclic olefin copolymer (COC) for reasons such as good dispersibility in polyethylene. It is particularly preferable to use an ethylene-cycloolefin copolymer in which is used as ethylene.

  In the present invention, the 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 above-mentioned cyclic olefin using a polymerization catalyst. .

  The cyclic olefin copolymer is produced by, for example, randomly polymerizing an α-olefin and a cyclic olefin having a predetermined molar ratio using a single site catalyst such as a metallocene catalyst or a multisite catalyst.

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

  It is preferable to use a cyclic polyolefin resin having a glass transition temperature (Tg) (for example, JIS K7121 etc.) of 60 ° C. or higher. By using a cyclic polyolefin resin having a glass transition temperature in such a range, excellent heat resistance can be maintained. As for cyclic polyolefin resin, it is especially preferable that the glass transition temperature (Tg) shall be 70 degreeC or more.

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

  When the intermediate layers 32 and 42 are made of the mixed resin, as the resin that can be used in combination with the cyclic polyolefin resin, the above-described polyethylene resins and polyolefin resins such as polypropylene resins can be used. 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 with respect to the entire mixed resin (the total of the cyclic polyolefin resin and the resin used in combination with the cyclic polyolefin resin). % Is preferable. By setting the content of the cyclic polyolefin resin within such a range, the easy tearability is favorably implemented. The content of the cyclic polyolefin resin is more preferably 60 to 90% by mass, and particularly preferably 60 to 80% by mass with respect to the entire mixed resin.

  In addition, although the layer containing cyclic polyolefin resin which is comprised with the above-mentioned mixed resin is preferably the intermediate layers 32 and 42 in the multilayer outer film 3 and the inner film 4, the outer film 3 and the inner film When the film 4 is a multilayer, there is no problem even if it is a layer other than the intermediate layers 32 and 42.

  In order to manufacture the tube-shaped film 21 which is the multiple film 2, it is preferable to obtain by the inflation film method, for example. The inflation film is in the form of a tube (cylinder) in advance, and can be used as manufactured, and there is an advantage that the film does not need to be formed into a cylinder in the subsequent process and no seam is produced. In addition, it is possible to 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 a tube shape from a extruder through a die is pulled up in the vertical direction, and the molten resin is expanded by air supplied in the process of being pulled up in the vertical direction. It is possible to obtain a roll in which the tubular film 21 is wound in a flat shape by forming a flat film while air cooling and winding it on a winding device.

  In the case where the multiple film 2 is a tube-shaped film 21, the outer film 3 and the inner film 4 that do not appear on the outer side and contact with each other (the inner layers 31 and 41 in FIG. 8 described above) block each other. It is preferable to adhere. Here, “blocking to each other” means that the films in contact with each other are not completely integrated by being bonded by another medium such as an adhesive or by heat-sealing. It means that the films are in a flexible state by pseudo-bonding. Blocking adhesion may occur over the entire surface of the film, or may occur partially on a part of the film. By carrying out blocking adhesion, the outer film 3 and the inner film 4 are integrated during bag making or the like, and the handleability is improved.

  In order to block-bond the tube-shaped film 21, for example, the polyolefin-based tube-shaped film formed by the above-described inflation film method is folded and pressed with a nip roll or the like, and folded while extruding air between the overlapped films. It can manufacture simply by winding up as a flat 2 layer film.

(2) Configuration of multiple film 2 (blocking adhesive film 22):
Next, another configuration of the multiple film 2 will be described. As the multiple film 2, it is possible to use a film (blocking adhesive film 22) having a structure in which an independent outer film 3 and inner film 4 are bonded to each other by blocking.

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

  The blocking adhesive film 22 to be the multiple film 2 is not only a film composed of a layer composed of the outer film 3 and the inner film 4 (hereinafter, may be referred to as “blocking adhesive layer”) which are blocking-adhered, and such blocking adhesive. The film which laminated | stacked another layer as the outer film 3 on the layer is also included.

  FIG. 9 is a cross-sectional view showing the layer structure of the blocking adhesive film 22 when the outer film 3 has three layers. 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 that is blocking-bonded. As shown in FIG. 9, in the blocking adhesive film 22, the surface in contact with the outer film 3 in the inner film 4 and the surface in contact with the inner film 4 in the layer constituting the outer film 3 (the surface of the inner layer 31) are blocking. It will be glued. Moreover, in the blocking adhesive film 22, when the inner film 4 comprises the back seal | sticker part 6 and the horizontal seal | sticker part 7, it will overlap and will be welded in direct contact.

  The resin constituting the blocking adhesive layer in the blocking adhesive film 22 (the inner film 4 and the inner layer 31 in the outer film 3) preferably has heat-sealing properties. For example, the polyethylene resin mentioned in the above (1) Alternatively, a polyolefin resin such as a polypropylene resin can be used. Of these polyolefin resins, polyethylene resins are preferably used, and among them, it is more preferable to use low density polyethylene (LDPE) excellent in heat sealability and the like, and linear low density polyethylene (LLDPE). ) Is particularly preferred.

  Moreover, as resin which comprises the outer layer 33 and the intermediate | middle layer 32 in the outer side film 3, in order to provide pinhole resistance and mechanical characteristics to the multiplex film 2, for example, the polyethylene-type resin mentioned above (1), 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 easy tear resin layer which consists of easy tear resin as the intermediate | middle layer 32 of the outer side film 3 similarly to the above-mentioned tube-shaped film 21. FIG. 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 (easy tearing property) of the multiple film 2 is improved. The content of the cyclic polyolefin resin, polyolefin resin, and cyclic polyolefin resin that can be used is the same as that of the mixed resin including the cyclic polyolefin resin described in the above (1), and thus the description thereof is omitted.

  In using the blocking adhesive film 22, when the outer film 3 has a 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 made of mixed resin of cyclic polyolefin resin and polyolefin resin (mixed resin layer) / Layer made of linear low density polyethylene (linear low density polyethylene layer), inner film is linear low density polyethylene layer It is preferable that By setting the outer film 3 and the inner film 4 as such a configuration, easy-openability (easy tearing property) can be imparted while maintaining heat sealability, pinhole resistance, and the like.

  In addition, the layer made of the mixed resin of the cyclic polyolefin resin and the polyolefin-based resin has no problem even if it is a layer other than the intermediate layer 32 in the multilayer outer film 3 and is the same as the tubular film 21.

  The method for forming the blocking adhesive layer to be blocked is not particularly limited, and a conventionally known technique can be used. For example, a tubular film extruded when a blown film is produced by a single-layer extrusion inflation method is folded. It is possible to manufacture by a method such as a method in which the inner surfaces of the film are blocked by online pressure-contacting with an on-line press and a take-up nip roll or a pressure-bonding roll newly provided after the take-up nip roll, and then wound into a roll. In addition, as another method, a film wound up separately without blocking is rolled off and the layers to be blocked are overlapped and aligned, and the film is blocked by thermocompression bonding between heated pressure rolls, etc. However, from the viewpoint of ease of operation, cost, and the like, it is preferable to use a method in which the above-described inflation molding is pressure-bonded and blocked.

  Here, the ease of blocking adhesion is appropriately changed depending on the type and density of the resin (polyolefin resin, etc.) used, the type and amount of additives such as lubricants and antiblocking agents, and the like. Generally, the higher the density of the resin and the greater the amount of additive, the more difficult it becomes to block. In addition, in order to adjust the blocking adhesive strength of the film that has been formed and folded by the inflation method, the folded tube-shaped film is passed through a roll such as a nip roll, a pressure-bonding roll, an embossing roll, or a heating roll. May be heated using a heating means such as a far-infrared lamp or a nichrome wire heater.

  In addition, the adhesive strength of the two layers to be bonded to the blocking layer only needs to be strong enough not to impair mechanical suitability due to unintentional blocking peeling in the film laminating step, slitting step, bag making or automatic filling bag making step. . The same applies to the case (1) where the inner layers 31 and 41 are subjected to blocking adhesion with the tubular 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, which is bonded through a predetermined adhesive or adhesive resin, is used. For example, in the case of the dry lamination method, it is common to use a one-component or two-component polyurethane adhesive, but this is not a limitation, and depending on the type of resin constituting the layer to be laminated, etc. The type of the adhesive may be selected as appropriate. As the adhesive resin, known adhesive resins such as EVA, ionomer PE, EAA, EMAA, and various modified resins may be used.

  In order to improve the adhesive strength between the films to be laminated, prior to lamination (or at the same time as the lamination), one or both of the layers to be laminated are subjected to corona discharge treatment. Surface treatment by ozone treatment, anchor coating agent application, or the like may be performed.

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

(1) Configuration of multiple film 2 (tubular film 21):
The tube-shaped film 21 is two films facing each other with both ends of a cylindrical film flattened in a flat shape and closed in a bag shape. As can be seen from FIG. 3 and FIG. 4, the tubular film 21 that is the multiple film 2 is one in which both side edges of the outer film 3 and the inner film 4 are continuous with each other, and the outer film 3 and the inner film 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 of the tubular film 21 when the outer film 3 and the inner film 4 have three layers. In FIG. 8, 3 is an outer film, 4 is an inner film, 31 and 41 are inner layers, 32 and 42 are intermediate layers, 33 and 43 are outer layers, and C is a gap.

  As shown in FIG. 8, in this embodiment, when the multiple film 2 is a tube-shaped film 21, both the outer film 3 and the inner film 4 are a mixture of a cyclic olefin resin and a polyolefin resin. A multilayer structure having intermediate layers 32 and 42 made of resin is formed. By interposing a layer composed of a mixed resin of the cyclic polyolefin resin and the polyolefin resin as the intermediate layers 32 and 42, the intermediate layers 32 and 42 become easy tear resin layers, and the easy-openability (easy tearability) of the multiple film is achieved. improves.

  As shown in an example in FIG. 8, when the outer film 3 and the inner film 4 are multilayered, the outer film 3 and the inner film 4 are viewed from the gap C formed between the outer film 3 and the inner film 4. From the outer side of the multiple bag 1 to the inner side of the multiple bag 1, the outer side of the multiple bag 1 / outer layer 33 / intermediate layer 32 / inner layer 31 (the above is the 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. Then, when the back seal portion 6 and the lateral seal portion 7 are formed, the layers corresponding to the outer layers 33 and 43 are overlapped and welded in direct contact with each other.

  As a resin constituting the layers other than the intermediate layers 32 and 42 as a resin constituting the tubular film 21, the layers corresponding to the outer layers 33 and 43 in FIG. 8 preferably have heat sealability in the layers themselves, For example, polyolefin resin 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), and copolymers with 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 ester copolymer, ethylene Acid modification by modifying polyethylene resins such as propylene copolymer, polypropylene resins, and polyolefin resins such as polyethylene and polypropylene with acrylic acid, methacrylic acid, maleic anhydride, fumaric acid, and other unsaturated carboxylic acids. Examples include polyolefin resins such as polyolefin resins. One of these resins may be used alone, or two or more thereof may be used in combination.

  Of these resins, it is preferable to use low-density polyethylene (LDPE), which has excellent heat-sealing properties, etc. Among low-density polyethylene, it has pinhole resistance, is tough and strong, and has mechanical strength, etc. In particular, it is particularly preferable to use linear low density polyethylene (LLDPE).

  The physical properties, mechanical strength, heat seal strength, and the like when linear low density polyethylene (LLDPE) is used are adjusted by the number of carbon atoms of the α-olefin to be copolymerized. In general, 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, heptene-1, etc. are preferably used. It is done.

  The density of the low density polyethylene (including the linear low density polyethylene) is preferably 0.870 to 0.935 g / cm 3. Various characteristics such as heat sealability are maintained by using low density polyethylene in a range where the density is high. The density of the low density polyethylene is particularly preferably from 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 minutes, and particularly preferably 0.5 to 4.0 g / 10 minutes.

  Further, in FIG. 8, as the resin constituting the layers corresponding to the inner layers 31 and 41, polyolefins such as the above-described polyethylene resins and polypropylene resins are provided so as to give the multiple film 2 pinhole resistance and mechanical properties. In addition to resin, polyamide resin (nylon), polyester resin (PET, PBT), ethylene-vinyl alcohol copolymer and the like can be used.

  Since the cyclic polyolefin resin constituting the mixed resin to be the intermediate layers 32 and 42 is the same as the cyclic polyolefin resin described in (B) (1) and the like, description thereof is omitted.

  In the mixed resin, as the resin used in combination with the cyclic polyolefin resin, the above-described polyethylene resins and polyolefin resins such as polypropylene resins can be used. 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 (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 within such a range, the easy tearability is favorably implemented. The content of the cyclic polyolefin resin is more preferably 60 to 90% by mass, and 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 configuration shown in FIG. 8, the outer film 3 is a layer made of linear low-density polyethylene in order from the outside of the multiple bag 1 (linear low-density polyethylene). Layer) / layer made of mixed resin of cyclic polyolefin resin and polyolefin resin (mixed resin layer) / layer made of polyolefin resin (polyolefin resin layer), inner film is the outer side of the multiple bag 1 (the aforementioned gap C) It is preferable that the polyolefin resin layer / mixed resin layer / linear low-density polyethylene layer be used in this order. By setting the outer film and the inner film as such, easy-opening property (easy tearing property) can be imparted while maintaining heat sealability, pinhole resistance and the like.

  In order to manufacture the tube-shaped film 21 which is the multiple film 2, it is preferable to obtain by the inflation film method, for example. The inflation film is in the form of a tube (cylinder) in advance, and can be used as manufactured, and there is an advantage that the film does not need to be formed into a cylinder in the subsequent process and no seam is produced. In addition, it is possible to 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 a tube shape from a extruder through a die is pulled up in the vertical direction, and the molten resin is expanded by air supplied in the process of being pulled up in the vertical direction. It is possible to obtain a roll in which the tubular film 21 is wound in a flat shape by forming a flat film while air cooling and winding it on a winding device.

  In the case where the multiple film 2 is a tube-shaped film 21, the outer film 3 and the inner film 4 that do not appear on the outer side and contact with each other (the inner layers 31 and 41 in FIG. 8 described above) block each other. It is preferable to adhere. Here, “blocking to each other” means that the films in contact with each other are not completely integrated by being bonded by another medium such as an adhesive or by heat-sealing. It means that the films are in a flexible state by pseudo-bonding. Blocking adhesion may occur over the entire surface of the film, or may occur partially on a part of the film. By carrying out blocking adhesion, the outer film 3 and the inner film 4 are integrated during bag making or the like, and the handleability is improved.

  In order to block-bond the tube-shaped film 21, for example, the polyolefin-based tube-shaped film formed by the above-described inflation film method is folded and pressed with a nip roll or the like, and folded while extruding air between the overlapped films. It can manufacture simply by winding up as a flat 2 layer film.

(2) Configuration of multiple film 2 (blocking adhesive film 22):
Next, the case where the multiple film 2 is the blocking adhesive film 22 will be described. As the multiple film 2, it is possible to use a film (blocking adhesive film) in which an independent outer film 3 and an inner film 4 are blocking-bonded.

  Here, “blocking adhesion” is as described above, and the films in contact with each other are not completely integrated by being bonded by another medium such as an adhesive or by heat fusion. It means that the films in contact are pseudo-bonded and in a flexible state. Blocking adhesion may occur over the entire surface of the film, or may occur partially on a part of the film. By carrying out blocking adhesion, the outer film 3 and the inner film 4 are integrated during 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 composed of the outer film 3 (inner layer 31 in FIG. 9) and the inner film 4 (hereinafter referred to as “blocking adhesive layer”). The outer film 3 has a structure in which an intermediate layer 32 made of a mixed resin of a cyclic polyolefin resin and a polyolefin resin and an outer layer 33 are further laminated.

  FIG. 9 is a cross-sectional view showing the layer structure of the blocking adhesive film 22 when the outer film 3 has three layers. 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 that is blocking-bonded. As shown in FIG. 9, in the blocking adhesive film 22, the surface in contact with the outer film 3 (inner layer 31 thereof) in the inner film 4 and the surface in contact with the inner film 4 in the inner layer 31 constituting the outer film 3 are blocked. It will be glued. Moreover, in the blocking adhesive film 22, when the inner film 4 comprises the back seal | sticker part 6 and the horizontal seal | sticker part 7, it will overlap and will be welded in direct contact.

  The content of the cyclic polyolefin resin, the polyolefin resin, and the cyclic polyolefin resin in the mixed 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 is as described in (1) Tubular Since it is the same as the content of the cyclic polyolefin resin, the polyolefin-based resin, and the content of the cyclic polyolefin resin in the mixed resin (described in the above (B)), the description is omitted.

  As the resin constituting the blocking adhesive layer in the blocking adhesive film 22 (the inner film 4 and the inner layer 31 in the outer film 3), for example, the polyolefin resin mentioned in the above (1) can be used. Of 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.

  Further, as the resin constituting the outer layer 33 in the outer film 3, in order to impart pinhole resistance and mechanical characteristics to the multiple film 2, in addition to polyolefin resins such as polyethylene resins and polypropylene resins, polyamide Resin (nylon), polyester resin (PET, PBT), ethylene-vinyl alcohol copolymer, etc. can be used.

  In using the blocking adhesive film 22, when the outer film 3 has a 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 made of mixed resin of cyclic polyolefin resin and polyolefin resin (mixed resin layer) / Layer made of linear low density polyethylene (linear low density polyethylene layer), inner film is linear low density polyethylene layer It is preferable that By setting the outer film 3 and the inner film 4 as such a configuration, easy-openability (easy tearing property) can be imparted while maintaining heat sealability, pinhole resistance, and the like.

  The blocking adhesive layer to be blocking-adhered is, for example, a tubular film extruded when a blown film is produced by a single-layer extrusion inflation method, folded and overlapped, and newly provided after the take-up nip roll or the take-up nip roll. It can be manufactured by a method such as a method in which a pressure roll is pressed online to block the inner surfaces of the film and are wound up into a roll. In addition, as another method, a film wound up separately without blocking is rolled off and the layers to be blocked are overlapped and aligned, and the film is blocked by thermocompression bonding between heated pressure rolls, etc. However, from the viewpoint of ease of operation, cost, and the like, it is preferable to use a method in which the above-described inflation molding is pressure-bonded and blocked.

  The ease of blocking adhesion of the films to be overlaid is appropriately changed depending on the type and density of the resin (polyolefin resin, etc.) used, the type and amount of additives such as lubricants and antiblocking agents, and the like. Generally, the higher the density of the resin and the greater the amount of additive, the more difficult it becomes to block. In addition, in order to adjust the blocking adhesive strength of the film that has been formed and folded by the inflation method, the folded tube-shaped film is passed through a roll such as a nip roll, a pressure-bonding roll, an embossing roll, or a heating roll. May be heated using a heating means such as a far-infrared lamp or a nichrome wire heater.

  In addition, the adhesive strength of the two layers to be bonded to the blocking layer only needs to be strong enough not to impair mechanical suitability due to unintentional blocking peeling in the film laminating step, slitting step, bag making or automatic filling bag making step. . The same applies to the case where the inner layers 31 and 41 are subjected to blocking adhesion in the above (1).

  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, which is bonded through a predetermined adhesive, is used. For example, in the case of the dry lamination method, it is common to use a one-component or two-component polyurethane adhesive, but this is not a limitation, and depending on the type of resin constituting the layer to be laminated, etc. The type of the adhesive may be selected as appropriate.

  In order to improve the adhesive strength between the films to be laminated, prior to lamination (or at the same time as the lamination), one or both of the layers to be laminated are subjected to corona discharge treatment. Surface treatment by ozone treatment, anchor coating agent application, or the like may be performed.

  In addition, the layer which consists of mixed resin of cyclic polyolefin resin and polyolefin resin does not have a problem also as layers other than an intermediate | middle layer in a multilayer outer film, This is the same as that of a tubular film.

(3) About the tear start part 51:
Next, the tear start part 51 formed in the multiple bag according to the present embodiment will be described. As shown in FIGS. 1 and 2, the multiple bag 1 according to the second embodiment of the present invention is torn against the palm portion 5 in which both ends of the multiple film 2 are overlapped so that the inner films 4 face each other. A start portion 51 is formed. The tear start portion 51 is formed to open substantially parallel to the lateral seal portion 7. For example, if the tear start portion 51 is formed so as to be substantially parallel to the lateral seal portion 7, the user can contact the lateral seal portion 7. On the other hand, it becomes easy to open it substantially parallel.

  The tear start part 51 formed in the palm part 5 weakens the initial tear strength and improves easy-openability. The tear start portion 51 can have an arbitrary shape such as a slit (cut), a V notch, an I notch, a perforation, or a microporous aggregate.

  As shown in FIGS. 1 and 2, the tear start portion 51 is preferably formed so as to reach at least the back seal portion 6 from the outer edge 52 of the palm portion. If the tear start portion 51 reaches the back seal portion 6, the tear can be smoothly drawn out at the time of opening, and the back seal portion 6 in which the multiple films 2 are gathered can be easily torn. It becomes the multiple bag 1 excellent in property. Moreover, there is no restriction | limiting in particular as the length of the tear start part 51, However, What is necessary is just about 5-20 mm in general.

  Further, the tear starting portion 51 may be configured as shown in FIG. 7 when a plurality of narrow line-shaped back seal portions 6 are formed. FIG. 7 is a front view showing another aspect of the multiple bag 1. FIG. 7 shows an aspect in which two back seal portions 6 are formed in a narrow line shape with respect to the palm portion 5. As described above, when a plurality of narrow line-shaped back seal portions 6 are formed, the tear start portion 51 is formed on the outer edge 52 side of at least the palm portion of the plurality of narrow line-shaped back seal portions 6. It is formed so as to reach the back seal portion 61 made. In addition, in this invention, the narrow line-shaped back seal parts 6 and 61 point out the back seal part 6 formed in the substantially linear form which has a width | variety about 2-10 mm by heat sealing (welding). . Moreover, what is necessary is just to make the number of the some back seal parts 6 and 61 into 2-5 in general.

(D) Manufacturing method of multiple bag 1 (common to first embodiment (first invention) and second embodiment (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 by using, for example, a vertical pillow type bag making machine. For example, the multiple film 2 is supplied from a roll around which the multiple film 2 is wound, and the supplied multiple film 2 is passed through a guide roll group, and then formed into a cylindrical shape by a former or the like, and a back seal bar. After the back seal portion 6 is formed, the filling is filled, and then the horizontal seal portion 7 is formed at the same time as the horizontal seal bar is cut, so that the multiple bag 1 shown in FIG. .

(E) Thickness of the multiple film constituting the multiple bag (common to the first embodiment (first invention) and the 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. 8 and 9, the inner layers 31, 41 and the outer layers 33, 43 are preferably about 10 to 70 μm, and the intermediate layers 32, 42 are It is preferably about 7 to 30 μm.

(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 portion 51 formed on the joint portion 5 of the multiple bag 1 composed of the multiple film 2 composed of the outer film 3 and the inner film 4 is a palm. Since it is formed so as to reach at least the back seal portion 6 from the outer edge 52 of the portion, it is possible to smoothly perform the tearing out at the time of opening, including the back seal portion 6 in which four films are gathered, and the multiple film It becomes the multiple bag 1 excellent in easy-openability which can tear 2 easily.

  In addition, the multiple bag 1 according to the second embodiment of the present invention described above includes at least the outer film 3 of the multiple bag 1 composed of the multiple film 2 composed of the outer film 3 and the inner film 4. Since the intermediate layers 32 and 42 made of a mixed resin with a series resin are included, the intermediate layers 32 and 42 become easy tear resin layers to facilitate tearing from the tear start portion 51 formed in the palm portion 5. The multiple bag 1 including the back seal portion 6 on which the sheets of film are gathered can be easily torn and the multiple bag 1 is excellent in easy-openability.

  The above-described multiple bag 1 can be used, for example, for transporting, storing, selling, etc., materials such as liquids, semi-fluids, powders, solids, pastes, etc., foods used for business use and industrial use. Especially, bags used for transporting liquid foods such as juice, mineral water, soft drinks, coffee, tea, green tea, seasonings, vegetable oil, mayonnaise, sauces, ketchup, juice, etc. This is useful as a multiple bag 1 for back-in-box. In the above-described manufacturing method, an example in which a bag is formed with the contents filled therein is shown, but there is a problem even if it is used in a state where the filling is not yet filled or a seal portion or the like is not formed. There is no.

  In addition, when used in a back-in box, the multiple bag 1 filled with the contents is transferred from the accommodated cardboard box to the predetermined container (bucket, etc.) as it is, and put in the predetermined container. In some cases, the contents are taken out and opened. When opening the multiple bag 1, it is not necessary if the entire circumference including not only the surface on which the palm portion 5 is formed but also the opposite surface is torn and the unnecessary portion torn from the multiple bag 1 is removed. Part becomes garbage and processing becomes troublesome. Therefore, it is preferable not to tear and remove the entire circumference, but to tear and open only the surface on which the palm portion 5 is formed, and to take out the contents without removing the torn portion from the multiple bag 1. .

(G) Variation of embodiment:
The aspect described above shows one aspect of the present invention, and the present invention is not limited to the above-described embodiment, and has the configuration of the present invention and can achieve the objects and effects. It goes without saying that modifications and improvements within the scope are included in the content of the present invention. Further, the specific structure, shape, and the like in carrying out the present invention are not problematic 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 within the scope that can achieve the object of the present invention are included in the present invention.

  For example, in the above-described embodiment, the tubular film 21 and the blocking adhesive film 22 are described as examples of the configuration of the multiple film 2, but the multiple film is not limited to these, and the outer film 3 and the inner film. A multi-film of any configuration consisting of 4 can be used.

  FIG. 8 shows a configuration in which the outer film 3 and the inner film 4 are three layers in the case of using a tubular film, but the outer film 3 and the inner film 4 are not limited to this configuration. 4 may have a layer structure of four or more layers. For example, another layer may be formed between the intermediate layers 32 and 42 and the outer layers 33 and 43, or between the intermediate layers 32 and 42 and the inner layers 31 and 41. As the resin constituting the other layers, the resins constituting the inner layers 31 and 41 and the intermediate layers 32 and 42 in the tubular film ((B) (1), (C) (1)) are used. can do.

  FIG. 9 shows a configuration in which the outer film 3 has three layers when the blocking adhesive film 22 is used. However, the outer film 3 is not limited to such a configuration, and the outer film 3 has a layer configuration of four or more layers. For example, another layer may be formed between the intermediate layer 32 and the outer layer 33, or between the intermediate layer 32 and the inner layer 31. As the resin constituting the other layer, the resin constituting the outer layer 33 and the intermediate layer 32 in the blocking adhesive film ((B) (2), (C) (2)) 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 a single layer, if the resin constituting the outer layers 33 and 43 in the tubular film 21 ((B) (1), (C) (1)) having the three-layer structure shown in FIG. 8 is used. Good. In the case of two layers, the resin that constitutes the outer layers 33 and 43 may be used for the layer that appears on the outside, and the inner layer described above for the layer that appears on the inner side (the layer facing the gap C). For example, a resin constituting the intermediate 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 a single layer, a resin or the like constituting the inner layer 31 in the blocking adhesive film 22 ((B) (2), (C) (2)) having a three-layer structure shown in FIG. 9 may be used. . Moreover, when it is set as two layers, the resin etc. which comprise the above-mentioned outer layer 33 and the intermediate | middle layer 32 can be used about the layer which appears outside, The resin which comprises the above-mentioned inner layer 31 about the layer which carries out blocking adhesion | attachment, etc. Can be used.

  In the present invention, for example, an “intermediate layer” such as an intermediate layer made of a mixed resin of a cyclic polyolefin resin and a polyolefin-based resin refers to an outer layer and an inner layer in a film (in the case of three layers, refer to FIGS. 8 and 9). In addition to the literal intermediate layer in the case of the three-layer configuration, the layers other than the outermost layer and the innermost layer in the configuration of four or more layers are also included in the “intermediate layer”.

  In the present invention, “a tear start portion 51 for opening substantially parallel to the lateral seal portion 7” is formed in the palm portion 5 for opening in the lateral direction (longitudinal direction of the lateral seal portion 7). For example, the tear start portion 51 is formed in the palm portion 5 and then opened in the longitudinal direction (longitudinal direction of the back seal portion 6) or the like in the lateral seal portion 7 or the like. A tear start portion (not shown) may be formed separately.

The above-described resin (resin material) constituting the multiple film 2 is, for example, a plasticizer, an antistatic agent, an antioxidant, a lubricant, an antifogging agent, and an ultraviolet absorber, as long as the effects of the present invention are not impaired. Various additives generally used in the field of resin materials, such as a heat stabilizer, a nucleating agent, a releasing agent, a coloring agent, and a neutralizing agent, may be added.
In addition, the specific structure, shape, and the like in the implementation of the present invention may be other structures as long as the object of the present invention can be achieved.

  INDUSTRIAL APPLICABILITY The present invention can be advantageously used for packaging and transporting materials and foods, and has high industrial applicability.

DESCRIPTION OF SYMBOLS 1 ... Multiple bag 2 ... Multiple film 21 ... Tubular film 22 ... Blocking adhesive film 3 ... Outer film 4 ... Inner film 31, 41 ... Inner layer 32, 42 ... Intermediate layer 33, 43 ... Outer layer 5 …… Joint part 51 …… Tear start part 52 …… Outer edge of joint part 6 …… Back seal part 61 …… Back seal part formed on outer edge side of joint part 7 …… Side seal part B …… Blocking Bonded surface C ...... Gap

Claims (4)

A palm portion is formed by overlapping both ends of the film so that the films face each other,
A back seal portion is formed by welding the films to be overlapped with each other at a predetermined width on the palm portion, and integrated.
A bag in which the contents are filled and sealed is formed by forming a lateral seal part in which the vicinity of both end edges on the side orthogonal to the back seal part is welded with a predetermined width,
The joint portion has a tear start portion formed to be substantially parallel to the lateral seal portion for opening so as to tear substantially parallel to the lateral seal portion,
The bag according to claim 1, wherein the tear start 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,
2. The bag according to claim 1, wherein the tear start portion is formed so as to reach at least the back seal portion formed on the outer edge side of the joint portion among the plurality of back seal portions. A palm portion is formed by overlapping both ends of the film so that the films face each other,
A back seal portion is formed by welding the films to be overlapped with each other at a predetermined width on the palm portion, and integrated.
A bag in which the contents are filled and sealed is formed by forming a lateral seal part in which the vicinity of both end edges on the side orthogonal to the back seal part is welded with a predetermined width,
The joint portion has a tear start portion formed to be substantially parallel to the lateral seal portion for opening so as to tear substantially parallel to the lateral seal portion,
At least the film has a multilayer structure having an intermediate layer made of a mixed resin of a cyclic polyolefin resin and a polyolefin resin.   The said mixed resin contains 3-99 mass% of said cyclic polyolefin resin with respect to the said mixed resin whole, The bag of Claim 3 characterized by the above-mentioned.

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