JP2020062811A - Laminate, liquid packaging bag, and liquid-containing packaging bag and manufacturing method therefor - Google Patents

Abstract

To provide a laminate capable of forming a packaging bag wide in filling capability temperature range and excellent in high speed filling property of a liquid.SOLUTION: There is provided a laminate in which an intermediate layer (B) containing an ethylene α-olefin copolymer (X) satisfying following requirements (x0) to (x3) and a sealant (C) are laminated, and at least a part of both are in contact each other. (x0) a copolymer of ethylene and α-olefin having 3 to 20 carbon atoms. (x1) MFR is 1 to 50 g/10 min. (x2) density is 900 to 925 kg/m. (x3) 0.30≤ΔH(80)/ΔH≤0.75, 0.35≤ΔH(100)/ΔH≤0.85, and 0.40≤ΔH(120)/ΔH≤0.95 are satisfied between total amount of fusion heat amounts ΔH in DSC and fusion heat amount ΔH(T) observed with temperature rising from 0°C to T°C.SELECTED DRAWING: None

Description

  The present invention relates to a laminate, a liquid packaging bag, a liquid-containing packaging bag, and a method for producing the same, and more specifically, a laminate preferably applied to a multilayer packaging film, a liquid packaging bag formed from the laminate, and the The present invention relates to a liquid-containing packaging bag using a liquid packaging bag and a method for manufacturing the same.

  Conventionally, a liquid or a viscous body, for packaging a liquid or a viscous body containing an insoluble matter, a multilayer packaging film composed of a laminate in which a sealant layer is laminated on a base material via an intermediate layer is used. There is known a liquid packaging bag in which a liquid or the like is filled through the opening of the bag-shaped product and the opening is closed by heat sealing.

  The packaging bag is often produced by heat-sealing the film on three sides or four sides, and when the liquid or the like is filled at a high speed, the liquid may leak from the heat-sealed portion. Therefore, there has been proposed a laminate for a packaging bag, which has improved high-speed filling properties.

  In Patent Documents 1 to 3, when used as a packaging bag for a liquid or a viscous substance in an automatic filling machine, the viscosity at a low shear rate is high, and the viscosity at a high shear rate is low. A method of using a resin composition having a ratio of a high shear rate and a low shear rate measured at a temperature close to filling in a specific range is disclosed. In particular, a composition of ethylene / 1-hexene copolymer and high-pressure low-density polyethylene is used in the intermediate layer between the base material and the sealant layer.

  Patent Document 4 discloses a packaging material having at least one sealant layer on a base film, wherein the sealant layer comprises an intermediate layer composed of an ethylene / α-olefin copolymer and a crystal nucleating agent, and an ethylene / α-olefin copolymer. A packaging material comprising an innermost layer made of a polymer is disclosed, the melting point of the intermediate layer is 90 to 120 ° C, the crystallization temperature is 80 to 110 ° C, and the difference between the melting point and the crystallization temperature is 25 ° C or less. It is said to be preferable.

  Further, in Patent Document 5, a polyethylene resin composition comprising a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms and a high pressure low density polyethylene (HPLD), having a specific density, MFR, It is disclosed to use a composition having specific elution properties for o-dichlorobenzene.

JP2012-139848A JP2012-139849A JP2012-139854A JP, 10-315409, A JP, 2007-204628, A

  When the opening of the packaging bag filled with the contents is closed by heat sealing, heat sealing is performed in a short time, so the temperature of the sealant layer needs to reach the temperature at which the sealing portion adheres in a short time. is there. However, when the heat sealing is performed in a short time, the temperature of the seal portion is likely to vary, and product defects (poor appearance, low pressure strength, etc.) due to the variation are likely to occur. Therefore, it is desired that the filling temperature range of the packaging bag (that is, the width of the heat-sealing temperature at which the packaging bag filled with the contents can be heat-sealed well) is wide.

  However, a conventional packaging bag formed from a multi-layer packaging film has a narrow temperature range in which it can be filled, and in particular, when the liquid is filled at a high speed (that is, when the opening of the packaging bag filled with the liquid is heat sealed at a high speed). Many product defects occurred due to variations in part temperature.

  In view of the above-mentioned problems in the prior art, it is an object of the present invention to provide a packaging bag having a wide fillable temperature range and a laminate capable of forming such a packaging bag.

  The present inventors use a polyethylene resin having a wide melting point distribution as the polyethylene resin used for the intermediate layer of the multilayer packaging film, thereby reducing the heat absorption amount in the intermediate layer at the time of heat-sealing, and the sealant layer. The inventors have found that the amount of heat transferred to the battery can be increased, thereby solving the above-mentioned problems, and have completed the present invention.

  The gist of the present invention is as follows.

[1]
An intermediate layer (B) containing an ethylene / α-olefin copolymer (X) satisfying the following requirements (x0) to (x3) and a sealant layer (C) are laminated, and at least one of the intermediate layers (B) is Part in contact with at least a part of the sealant layer (C):
(X0) It is a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms.
(X1) The melt flow rate measured at 190 ° C. under a load of 2.16 kg is 1 to 50 g / 10 minutes.
(X2) The density is 900 to 925 kg / m ³ .
(X3) Using a differential scanning calorimeter, the temperature was raised from 0 ° C. to 200 ° C. at a rate of 10 ° C./minute, held at 200 ° C. for 10 minutes, lowered to 0 ° C. at a rate of 10 ° C./minute, and then 0 ° C. For 10 minutes, and then at the second heating when heating to 200 ° C at a rate of 10 ° C / min, the total amount of heat of fusion observed is ΔH, When the observed heat of fusion is ΔH (T),
0.30 ≤ ΔH (80) / ΔH ≤ 0.75
0.35 ≤ ΔH (100) / ΔH ≤ 0.85, and
0.40 ≤ ΔH (120) / ΔH ≤ 0.95
Is.

[2]
A substrate layer (A) is further laminated on a surface of the intermediate layer (B) opposite to the sealant layer (C) side, and at least a part of the intermediate layer (B) and the substrate layer ( Is in contact with at least part of A),
The laminate of [1], wherein the sealant layer (C) contains an ethylene / α-olefin copolymer (Y) satisfying the following requirements (y0) to (y2):
(Y0) A copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms.
(Y1) The melt flow rate measured at 190 ° C. under a load of 2.16 kg is 1 to 50 g / 10 minutes.
(Y2) The density is 880 to 920 kg / m ³ .

[3]
The base material layer (A) is at least one selected from the group consisting of polyamide resin, polyester resin, polyolefin resin, polyvinylidene chloride resin, saponified ethylene-vinyl acetate copolymer, polycarbonate resin, polystyrene resin and acrylic resin. The laminate according to the above [2], which comprises, as a substrate, at least one selected from the group consisting of a film containing one kind of thermoplastic resin and its stretched product, a metal foil, a ceramic vapor deposition film, paper, and a non-woven fabric.

[4]
The base material layer (A) has at least a part of the surface of the base material, and at least one adhesive selected from the group consisting of polyurethane, an isocyanate compound, a polyester, and a mixture of a polyol and an isocyanate compound and a reaction product. A laminate of the above [2] or [3], which comprises an adhesive layer made of an agent and is in contact with the intermediate layer (B) through the adhesive layer.

[5]
A liquid packaging bag formed from the laminate according to any one of [1] to [4].

[6]
A liquid-containing packaging bag comprising the liquid packaging bag of [5] and a liquid or a viscous substance contained in the liquid packaging bag.

[7]
And a step of filling the liquid packaging bag of [5] with a liquid or a viscous material to produce the packaging bag containing the liquid of [6],
The liquid-containing packaging bag is a liquid-containing packaging that is manufactured in a state of a sheet in which a plurality of the liquid-containing packaging bags are continuous in the longitudinal direction and at a feeding speed of the sheet in the longitudinal direction of 20 m / min or more. Bag manufacturing method.

  According to the laminated body of the present invention, it is possible to form a packaging bag having a wide fillable temperature range. As a result, the tolerance for variations in the temperature of the seal portion when the packaging bag is filled with the contents is widened, so that the defective rate of the product (for example, the packaging bag containing the liquid) can be reduced.

  The liquid packaging bag according to the present invention has a wide fillable temperature range, and is therefore excellent in high-speed liquid filling property.

  Hereinafter, the present invention will be described in more detail.

[Laminate]
The laminate according to the present invention is formed by laminating an intermediate layer (B) and a sealant layer (C), and at least a part of the intermediate layer (B) and at least a part of the sealant layer (C) are in contact with each other. It is characterized by doing.

  In the laminate according to the present invention, the base material layer (A) is optionally further laminated on the intermediate layer (B) on the surface opposite to the surface on which the sealant layer (C) is formed, whereby a multilayer packaging film. Can be used as However, the application of the laminate of the present invention is not limited to the multilayer packaging film.

  When the laminate according to the present invention is used as a multilayer packaging film, the intermediate layer (B) may be formed over the entire area between the base material layer (A) and the sealant layer (C). Of course, if the multilayer packaging film is formed into a bag shape, the intermediate layer (B) may be formed only in a part near the portion to be heat-sealed.

<Base material layer (A)>
The base material layer (A) includes a base material, and optionally further includes an adhesive layer described below.

  The base material forming the base material layer (A) is one outer surface of the multilayer packaging film, and has relatively large rigidity and strength. Specific examples of the base material include polyamide resins such as nylon 11 and nylon 12, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polyolefin resins such as polyethylene resin and polypropylene resin, polystyrene resins, polyvinylidene chloride resins, and polycarbonate. A film containing a resin, a saponified product of ethylene-vinyl acetate copolymer, and a thermoplastic resin such as an acrylic resin (or a stretched product thereof), a metal vapor deposition film, a ceramic vapor deposition film such as an inorganic oxide vapor deposition film. At least one selected from the group consisting of film, metal foil, paper, and non-woven fabric is included. Two or more kinds of these base materials may be laminated and used.

  The metal foil is not particularly limited depending on the material and the thickness, and has a thickness of 5 to 50 μm such as aluminum foil, tin foil, lead foil, zinc-plated thin steel sheet, thin film of ionized metal by electrolysis method, iron foil. Etc. are used.

  Also, the metal vapor deposition film is not particularly limited depending on the material and thickness, and examples of the vapor deposition metal include aluminum and zinc, and the thickness of the vapor deposition metal layer is usually about 0.01 to 0.2 μm. . The vapor deposition method is also not particularly limited, and a known method such as a vacuum vapor deposition method, an ion plating method, or a sputtering method can be used.

  In the ceramic vapor-deposited film, examples of the ceramic to be vapor-deposited include silicon oxide represented by the general formula SiOx (0.5 ≦ x ≦ 2), and metal oxides such as glass, alumina, magnesium oxide, and tin oxide. And metal fluorides such as fluorite and selenium fluoride. The metal oxide may contain a trace amount of metal, other metal oxide, or metal hydroxide. Vapor deposition can also be performed by applying the above various vapor deposition methods to at least one surface of the film. The thickness of the vapor deposition film is usually about 10 to 50 μm. Further, the film to be vapor-deposited is not particularly limited, and examples thereof include a transparent film such as a stretched polyester film, a polypropylene film and a polyamide film.

  Further, in the base material layer (A), at least a part of the surface of the base material is bonded to at least one kind selected from the group consisting of polyurethane, an isocyanate compound, a polyester, a mixture of a polyol and an isocyanate compound, and a reaction product. By laminating an adhesive layer made of an agent and bringing the base layer (A) and the intermediate layer (B) into contact with each other through the adhesive layer, the base layer (A) and the intermediate layer (B) It is preferable to improve the adhesiveness of.

  Thus, the resin layer and / or the metal layer and / or the paper layer is used for the base material layer (A).

<Intermediate layer (B)>
The intermediate layer (B) is formed of a material containing an ethylene / α-olefin copolymer (X) (hereinafter also referred to as “copolymer (X)”) satisfying the following (x0) to (x3).

Requirement (x0):
The requirement (x0) is that the ethylene / α-olefin copolymer (X) is a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms.

  The α-olefin is preferably an α-olefin having 4 to 8 carbon atoms, and examples of the α-olefin include propylene, 1-butene, 1-hexene, 1-pentene and 4-methyl-1-pentene. , 1-heptene, 1-octene and 1-decene. These may be used alone or in combination of two or more.

  The ratio of the α-olefin-derived structural unit in the ethylene / α-olefin copolymer (X) and the type of the α-olefin are appropriately adjusted so that the requirements (x1) to (x3) are satisfied.

Requirement (x1):
The requirement (x1) is that the melt flow rate measured at 190 ° C. under a load of 2.16 kg according to JIS K7210-1 is 1 to 50 g / 10 minutes, preferably 3 to 30 g / 10 minutes, More preferably, it is in the range of 4 to 20 g / 10 minutes. When the melt flow rate is within the above range, the extrusion processability during the formation of the intermediate layer is improved.

Requirement (x2):
The requirement (x2) is that the density measured according to JIS K7112 is 900 to 925 kg / m ³ , and preferably 910 to 925 kg / m ³ .

Requirement (x3):
In general, the melting peak of low-density polyethylene has an endothermic peak having a plurality of peaks around 30 ° C., which is broader than that of high-density polyethylene. Usually, the highest peak temperature of the melting peak is the melting point. The DSC measurement is performed under the conditions shown in the examples below. That is, the requirement (x3) is that, using a differential scanning calorimeter, the ethylene / α-olefin copolymer (X) is heated from 0 ° C to 200 ° C at a rate of 10 ° C / min and held at 200 ° C for 10 minutes. Melting observed at the second temperature rise when the temperature is lowered to 0 ° C at a rate of 10 ° C / min, the temperature is maintained at 0 ° C for 10 minutes, and then the temperature is raised to 200 ° C at a rate of 10 ° C / min. Let ΔH be the total amount of heat and ΔH (T) be the heat of fusion observed at a temperature rise from 0 ° C to T ° C.
0.30 ≤ ΔH (80) / ΔH ≤ 0.75
0.35 ≤ ΔH (100) / ΔH ≤ 0.85, and
0.40 ≤ ΔH (120) / ΔH ≤ 0.95
Is satisfied. Preferably
0.31 ≤ ΔH (80) / ΔH ≤ 0.60
0.40 ≤ ΔH (100) / ΔH ≤ 0.75, and
0.50 ≤ ΔH (120) / ΔH ≤ 0.90
Is.

  When the contents are filled in a packaging bag made of a multilayer packaging film, heat sealing is performed in a very short time, and adhesion of the seal portion occurs before the temperature of the sealant layer reaches the temperature of the seal bar. It cannot be filled without it. Therefore, if the heat transfer property of the intermediate layer is good, even if the temperature of the seal bar is low, the temperature of the sealant layer rises in a short time, so that filling is possible. That is, the temperature range in which filling is possible becomes wider. In order to improve the heat conductivity of the intermediate layer, it is necessary to reduce the amount of the resin component of the intermediate layer that melts at the melting point of the resin of the sealant layer.

  However, in order to do so, when a resin having a higher melting point and a narrower melting point distribution than the resin for the sealant layer is used as the resin for the intermediate layer, the resin density of the intermediate layer becomes high, and the rigidity of the intermediate layer increases. Since the temperature becomes too high, wrinkles are generated in the packaging bag at the time of filling, or defective sealing at the half-folded portion of the packaging bag occurs, resulting in defective filling.

  Therefore, in the laminate of the present invention, as the polyethylene-based resin for the intermediate layer (B), the ethylene / α-olefin copolymer (X) that satisfies the requirement (x3), that is, has a wide melting point distribution is used. There is. Therefore, it is possible to reduce the amount of heat absorption in the intermediate layer during heat sealing without increasing the rigidity of the intermediate layer, increase the amount of heat transferred to the sealant layer, and thereby widen the temperature range in which filling is possible. Become.

  The values of H (80) / ΔH, ΔH (100) / ΔH and ΔH (120) / ΔH defined as the requirement (x3) are, for example, the resin used as the main component, a resin having a higher melting point, or It can be adjusted by further blending a resin having a low melting point.

  The copolymer (X) can be prepared using a metallocene-based, titanium-based, chromium-based or phenoxyimine-based olefin polymerization catalyst. The copolymer (X) may be linear or branched low density polyethylene. In particular, when prepared using a metallocene-based olefin polymerization catalyst, a polymer having a narrow molecular weight distribution can be obtained, so that a low-molecular weight and low-density component is less likely to be produced, which is effective for the application of the present invention.

  The metallocene catalyst is usually a metallocene catalyst component (a1) consisting of a transition metal compound of Group IVB of the periodic table having at least one ligand having a cyclopentadienyl skeleton, an organoaluminum oxy compound catalyst component (b). , A particulate carrier (c), and optionally an organoaluminum compound catalyst component (d) and an ionized ionic compound catalyst component (e).

  Such a copolymer (X) is described in, for example, JP-A-6-9724, JP-A-6-136195, JP-A-6-136196, JP-A-6-207057 and the like. It can be produced by copolymerizing ethylene and an α-olefin having 3 to 20 carbon atoms in the presence of a so-called metallocene-based olefin polymerization catalyst containing a catalyst component.

  The copolymer (X) may be one type of copolymer or a mixture of two or more types of copolymers. In the case of the mixture, the mixture may satisfy the above requirements (x0) to (x3), and each polymer before mixing may not satisfy the above requirements.

  As the copolymer (X), those satisfying the above (x0) to (x3) may be selected from commercially available ethylene / α-olefin copolymers.

<Sealant layer (C)>
As the sealant layer (C), a conventionally known sealant layer used in a multilayer packaging film can be used, but an ethylene / α-olefin copolymer (Y) satisfying the following requirements (y0) to (y2) is used. It is preferred to use a sealant layer formed from the material containing.

Requirement (y0):
The requirement (y0) is that the ethylene / α-olefin copolymer (Y) contains a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms.

  Examples of the α-olefin having 3 to 20 carbon atoms include propylene, 1-butene, 1-hexene, 1-pentene, 4-methyl-1-pentene, 1-heptene, 1-octene and 1-decene. Can be mentioned. These may be used alone or in combination of two or more.

  The ratio of the α-olefin-derived structural unit in the ethylene / α-olefin copolymer (Y) and the type of the α-olefin are appropriately adjusted so that the requirements (y1) to (y2) are satisfied.

Requirement (y1):
The requirement (y1) is such that the ethylene / α-olefin copolymer (Y) has a melt flow rate of 1 to 50 g / 10 minutes, preferably 2 to 40 g / 10 minutes, more preferably measured at 190 ° C. under a load of 2.16 kg. Is 4 to 30 g / 10 minutes. When the melt flow rate is within this range, the extrusion processability during formation of the heat seal layer is good.

Requirement (y2):
The requirement (y2) is that the density of the ethylene / α-olefin copolymer (Y) is 880 to 920 kg / m ³ . The density is preferably 902 to 910 kg / m ³ . When the density is within this range, good filling properties can be obtained when the packaging bag formed from the laminate according to the present invention is liquid-filled.

  In consideration of heat sealability at a lower temperature, the ethylene / α-olefin copolymer (Y) forming the sealant layer (C) is the ethylene / α-olefin copolymer forming the intermediate layer (B). It is preferable to have a melting point lower than that of (X) (that is, a melting peak temperature at the time of the second heating by the differential scanning calorimeter used for the requirement (x3)).

  The ethylene / α-olefin copolymer (Y) can be prepared by using a metallocene-based, titanium-based, chromium-based or phenoxyimine-based olefin polymerization catalyst. The ethylene / α-olefin copolymer (Y) may be linear or branched low density polyethylene. In particular, when a metallocene-based olefin polymerization catalyst is used for the preparation, a polymer having a narrow molecular weight distribution can be obtained, so that a low-molecular weight and low-density component is less likely to be produced, which is effective for the application of the present invention.

  The metallocene catalyst is usually a metallocene catalyst component (a1) consisting of a transition metal compound of Group IVB of the periodic table having at least one ligand having a cyclopentadienyl skeleton, an organoaluminum oxy compound catalyst component (b). , A particulate carrier (c), and optionally an organoaluminum compound catalyst component (d) and an ionized ionic compound catalyst component (e).

  The ethylene / α-olefin copolymer (Y) is described, for example, in JP-A-6-9724, JP-A-6-136195, JP-A-6-136196 and JP-A-6-207057. It can be produced by copolymerizing ethylene with an α-olefin having 3 to 20 carbon atoms in the presence of a metallocene olefin polymerization catalyst containing a metallocene catalyst component.

  The ethylene / α-olefin copolymer (Y) may be a single type of copolymer, or a mixture of two or more types of ethylene / α-olefin copolymers, or ethylene / α-olefin. It may be a mixture of one or more olefin copolymers and one or more other polyethylenes. In the case of a mixture, the mixture may satisfy the above requirements (y0) to (y2), and each polymer before mixing may not satisfy the above requirements.

  As the ethylene / α-olefin copolymer (Y), commercially available ethylene / α-olefin copolymers satisfying the above (y0) to (y2) may be used.

  If necessary, the resin (resin composition) constituting the intermediate layer (B) or the laminate layer (C) may have a conventionally known anti-blocking agent, anti-fogging agent, antistatic agent, antioxidant, weathering stability. Additives such as agents, heat stabilizers, and lubricants may be blended within a range that does not impair the object of the present invention.

  When the intermediate layer (B) or the laminate layer (C) is formed from the resin composition containing the copolymer and the additive, the resin composition is the ethylene / α-olefin copolymer (X) or the ethylene / α. -Olefin copolymer (Y) is obtained by mixing the above-mentioned additives at a room temperature to 250 ° C using a mixing device such as a Banbury mixer, a Henschel mixer, a V-type blender and an extruder. At this time, by performing a nitrogen seal or a vacuum seal, it is possible to prevent the generation of a gel due to the deterioration of the ethylene / α-olefin copolymer.

<Manufacture of laminated body>
For example, by stacking the intermediate layer (B) and the sealant layer (C) in contact with each other in a molten state on the base material layer (A), the base material layer (A), the intermediate layer (B) and the It is possible to obtain the laminate according to the present invention, which has excellent adhesiveness to the sealant layer (C). The contact of the intermediate layer (B) in the molten state can be performed by melt-extruding the intermediate layer (B) on the base material layer (A). Further, the laminate of the present invention is produced by molding the base material layer (A) with the resin materials used for the intermediate layer (B) and the sealant layer (C) separately or simultaneously by melt extrusion. can do.

  The molding temperature of the intermediate layer (B) and the sealant layer (C) is preferably 150 to 320 ° C., and within this range, the base material layer (A), the intermediate layer (B), and the intermediate layer (B). ) And the sealant layer (C) have good adhesiveness.

  When the intermediate layer (B) is melt-extruded on the base material layer (A), an anchor coat treatment is applied to the surface of the base material (A) on which the intermediate layer (B) is extrusion-molded. And that the anchor-coated substrate was brought into contact (hereinafter referred to as “ozone treatment”) with an oxidizing atmosphere (for example, gas containing oxygen, particularly ozone (air, etc.)) within the above molding temperature range. It is preferable to use it from the viewpoint of adhesiveness.

  The anchor coat treatment is performed on the basis of a known anchor coat agent such as polyurethane, isocyanate compound, or mixture and reaction product thereof, reaction product, polyester, or mixture and reaction product of polyol and isocyanate compound, or solution thereof, and adhesive. It is done by applying to the surface of the material.

  When the laminate of the present invention is used as a multilayer packaging film, each of the optional base material layer (A), the intermediate layer (B) and the sealant layer (C) is one layer, for a total of two layers (optionally three layers). The structure is the basic structure of the multilayer packaging film. Each of the base material layer (A), the intermediate layer (B) and the sealant layer (C) may be a single layer, but in some cases, each of the layers may be composed of a plurality of layers. For example, a two-layer film obtained by dry laminating a polyester film and a ceramic vapor-deposited polyester film can be used as the base material layer (A). When one layer of the intermediate layer (B) and one layer of the sealant layer (C) are laminated on the base material layer (A) composed of a two-layer film, a laminated body of four layers in total is obtained. Further, for example, when a polyester film and an aluminum foil are dry-laminated and further a polyester film is dry-laminated on the aluminum foil surface for a total of three layers to be used as the base material layer (A), a five-layer structure is formed.

  The intermediate layer (B) and the sealant layer (C) are usually used as a single layer (only one layer). In the present invention, as long as at least a part of the intermediate layer (B) and at least a part of the sealant layer (C) are in contact with each other, another layer may be present between the two in another part.

  Further, at least a part of the base material layer (A) and at least a part of the laminate including the intermediate layer (B) and the sealant layer (C) may be in contact with each other. In the case of using for heat sealing, a laminated structure of the base material layer (A) / intermediate layer (B) / sealant layer (C) may be used in the heat sealed portion.

  Another layer may exist between the base material layer (A) and the intermediate layer (B) in another portion, and the base material layer (A) and the sealant layer (without the intermediate layer (B) being interposed. There may be a portion in contact with C). Examples of the other layer include a layer made of an olefin polymer other than the resin used for the intermediate layer (B) and the sealant layer (C), an air layer, and the like.

In the ozone treatment, a gas (air or the like) containing ozone from a nozzle or a slit-shaped outlet is bonded to the base layer (A) of the intermediate layer (B) in the air gap, or the base layer ( It is performed by directing it toward the surface of (A) which is bonded to the intermediate layer (B) or by spraying toward the pressure-bonded portion of both. When extrusion laminating is performed at a speed of 100 m / min or more, it is preferable to spray toward the pressure-bonded portions of the both. The concentration of ozone in the gas containing ozone is preferably 1 g / m ³ or more, more preferably 3 g / m ³ or more. The amount of spray is preferably 0.03 liter / (min · cm) or more, more preferably 0.1 liter / () with respect to the width of the intermediate layer (B) (length in the direction perpendicular to the extrusion direction). Min./cm) or more.

  The laminating speed is generally 100 to 150 m / min from the viewpoint of productivity. The air gap of a known extrusion laminator is generally 100 to 150 mm. The laminate of the present invention is preferably subjected to aging treatment immediately after molding, from the viewpoint of adhesiveness. Aging is performed by allowing the laminate to stand within 12 hours after its molding, at a temperature of 23 to 45 ° C., preferably 35 to 45 ° C., and an atmosphere of 0 to 50% humidity for 12 to 24 hours. .

  In the laminated body thus obtained, the thickness of the base material layer (A) is 10 to 50 μm, the thickness of the intermediate layer (B) is 10 to 50 μm, and the thickness of the sealant layer (C) is 5 to 100 μm. Is generally.

[Liquid packaging bag, packaging bag containing liquid, and manufacturing method thereof]
The laminate of the present invention is particularly useful as a material for a liquid packaging bag filled with a liquid or a viscous material.

  The liquid packaging bag of the present invention is formed from the laminate of the present invention, and more specifically, it comprises any of the above-mentioned base material layer (A) / intermediate layer (B) / sealant layer (C). One piece of the laminate (multilayer packaging film) laminated in order is bent so that the sealant layer (C) faces each other, or two pieces are stacked so that the sealant layer (C) faces each other, or the laminate of the present invention (multilayer). (Wrapping film) and another film are laminated so that the sealant layer (C) and the other film face each other, and heat-sealed (for example, two-sided seal, three-sided seal or four-sided seal) into a bag shape. . The heat sealing can be performed by a conventional method using a conventionally known heat sealing machine. The shape of the bag is generally rectangular, but can be any shape.

  The liquid-containing packaging bag of the present invention comprises the liquid packaging bag of the present invention and the liquid or the viscous body contained in the liquid packaging bag. In addition, in the present invention, even when the contained material is a viscous body, it is referred to as a liquid packaging bag or a liquid-containing packaging bag for convenience.

  Examples of liquids or mucilages include foods and pharmaceuticals. In addition, a solid matter may be contained in the liquid or the viscous body, such as a dressing containing granules.

  The heat sealing may be performed at a temperature equal to or higher than the melting temperature of the sealant layer (C), and the heat sealing width may be appropriately set according to the amount of the liquid or the viscous substance filled in the liquid packaging bag. Further, in order to make it easier to take out the liquid or the viscous material from the bag, it is possible to perform heat sealing while leaving a portion serving as a spout.

  The liquid-filled packaging bag of the present invention can be manufactured through a step of filling the liquid packaging bag of the present invention with a liquid or a viscous body. The liquid-containing packaging bag can be manufactured as a continuous sheet. Since the liquid-containing packaging bag of the present invention uses the liquid packaging bag of the present invention having a wide filling temperature range, it is high speed when manufactured as the above-mentioned sheet, that is, the feeding speed in the longitudinal direction of the sheet. Of 20 m / min or more, preferably 25 m / min or more. The upper limit value may be, for example, 30 m / min, although it depends on the capacity of the filling machine.

  Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.

(Copolymer for intermediate layer)
As a material for the intermediate layer, the ethylene / α-olefin copolymer shown in Table 1 was prepared.

[Example 1]
The laminate film was produced by the extrusion laminating method as follows.

  First, a polyurethane-based anchor coat agent (Mitsui Chemicals, Inc.), a polyol component: "Takelac" was placed on a biaxially stretched nylon film (“Hayden (registered trademark) ONY # 15” manufactured by Toyobo Co., Ltd.) having a width of 500 mm and a thickness of 15 μm. (Registered trademark) A-3210 "and an isocyanate component:" Takenate (registered trademark) A-3075 ") were applied by a gravure roll to obtain a base material coated with the anchor coating agent.

  Next, using an extrusion laminating apparatus in which the temperature of the resin extruded from the T die of an extruder having a diameter of 60 mmφ was set to 295 ° C., the cooling roll surface temperature was 30 ° C., the die width was 500 mm, and the die lip opening was 0.9 mm. Under the conditions, the extrusion rate is adjusted so that the coating thickness is 25 μm when the processing speed is 80 m / min, and the intermediate is applied to the base material coated with the anchor coating agent while spraying ozone in the laminating section. PE-1 as a layer material was extruded under a condition of a take-up speed of 80 m / min and a coating thickness of 25 μm to carry out extrusion laminating to form an intermediate layer.

Further, using the same extrusion laminating apparatus on the intermediate layer, a product name “Evolue (registered trademark) P SP05156C” (MFR: 12 g / 10 min, density: 904 kg / m ³ ) manufactured by Prime Polymer Co., Ltd. was extruded at a resin temperature of 295. Extrusion lamination processing was performed by extruding under conditions of ° C, a take-up speed of 80 m / min and a coating thickness of 25 µm to form a sealant layer to obtain a laminate. The laminate was put in an oven at 40 ° C., aged for 24 hours, and then slits were formed in the laminate so that the width was 150 mm, to obtain a packaging film for evaluation.

  The physical properties of the material for the intermediate layer and the liquid filling suitability of the obtained packaging film were evaluated by the methods described below. The results are shown in Table 2.

[Comparative Examples 1, 2, 3]
A packaging film for evaluation was obtained by the same method as in Example 1 except that PE-2, PE-3, and PE-4 were used as the materials for the intermediate layer.

  The physical properties of the intermediate layer material and the liquid filling suitability of the obtained packaging film were evaluated by the methods described below. The results are shown in Table 2.

<Melt flow rate (MFR)>
According to JIS K7210-1, it was measured under the conditions of 190 ° C. and 2.16 kg load.

<Density>
According to JIS K7112, the strand obtained at the time of MFR measurement was heat-treated at 100 ° C. for 1 hour, left at room temperature for 1 hour, and then measured by a density gradient tube method.

<Melting point peak, heat of fusion, ΔH (T) / ΔH>
The crystal melting point can be determined according to JIS K7121 by using a differential scanning calorimeter (DSC, manufactured by Perkin Elmer (Diamond DSC)) under the following measurement conditions. The peak of the endothermic peak in the third step when measured under the following measurement conditions was defined as the crystal melting point (Tm). When there are a plurality of endothermic peaks, the peak of the endothermic peak that maximizes the peak height is defined as the crystal melting point (Tm).

《ΔH (T) / ΔH》
A differential scanning calorimeter (DSC, manufactured by Perkin Elmer (Diamond DSC)) was used to measure the differential scanning calorimeter under the following measurement conditions.

(Measurement condition)
Measurement environment: Nitrogen gas atmosphere Sample amount: 5 mg
Sample shape: Press film (230 ℃ molding, thickness 400μm)
Sample pan: Aluminum sample pan having a flat bottom Step 1: Raise the temperature from 0 ° C to 200 ° C at a rate of 10 ° C / min and hold for 10 minutes.

  Second step: Cool down to 0 ° C at a rate of 10 ° C / min.

  Third step: The temperature is raised to 200 ° C. at a rate of 10 ° C./min.

  The total amount of heat of fusion obtained in the third step is ΔH, and the amount of heat of fusion when the temperature is raised from 0 ° C to T ° C is defined as ΔH (T). ΔH when T is 80, 100 or 120 (° C) (T) / ΔH, that is, ΔH (80) / ΔH, ΔH (100) / ΔH and ΔH (120) / ΔH were calculated.

<Liquid packaging bag filling method and liquid filling suitability evaluation>
Using a high-speed automatic filling and packaging machine (DANGAN TYPE-III manufactured by Taisei Lamick Co., Ltd.), a packaging bag is produced under the following conditions from the packaging film produced in Examples and the like, and a liquid is filled therein to form a liquid. A filled pouch was obtained.

Sealing temperature: (vertical sealing temperature) 190 ° C., (horizontal sealing temperature) in steps of 5 ° C. in the range of 140 to 185 ° C. (The upper limit is 185 ° C., because the nylon base material itself shrinks and the appearance becomes poor, so the evaluation range is It is non-conforming.)
Packaging form: Three-sided seal Bag size: Width 75 mm × length 85 mm pitch Filling material: water at 23 ° C Filling amount: about 24 cc
Filling speed: 25 m / min The appearance of the lateral seal portion of the obtained liquid-filled pouch was observed and a pressure test was conducted, and the following criteria were evaluated.

[Appearance of seal part: Evaluation of suitability for high temperature filling (maximum foaming resistance temperature)]
For each liquid-filled pouch with a different horizontal sealing temperature, the appearance of the horizontal sealing portion was evaluated according to the following criteria. It is desirable that the maximum horizontal seal temperature (maximum anti-foaming temperature) at which foaming or poly pool does not occur in the horizontal seal portion is higher.

◯: No poly pool (state in which the sealant layer and the intermediate layer are bulged like a bump) and no foaming △: Liquid leak at the seal part x: Poly pool and many foams [Pressure resistance: low temperature filling suitability (minimum pressure temperature) Evaluation]
A pressure tester (manufactured by Komatsu Ltd.) applied a load of 100 kg to each liquid-filled sachet with a different horizontal sealing temperature for 1 minute, and evaluated the pressure resistance of the liquid-filled sachet based on the following criteria. Occurrence of bag breakage or water leakage Not evaluated at the lowest temperature. A lower minimum withstand temperature is desirable.

○: No abnormality △: Liquid leakage from half-folded part ×: Lateral seal receded

  As is clear from Table 2, since the laminate according to the present invention uses the ethylene / α-olefin copolymer (X) according to the present invention as a material for the intermediate layer, it has a wide filling temperature range and is excellent. It showed a fast filling property of liquid. In Comparative Examples 1, 2, and 3, the condition (x3) was not satisfied as the material for the intermediate layer, so that the temperature range in which filling was possible was narrower than that in Example 1.

Claims (7)

An intermediate layer (B) containing an ethylene / α-olefin copolymer (X) satisfying the following requirements (x0) to (x3) and a sealant layer (C) are laminated, and at least one of the intermediate layers (B) is Part in contact with at least a part of the sealant layer (C):
(X0) A copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms.
(X1) The melt flow rate measured at 190 ° C. under a load of 2.16 kg is 1 to 50 g / 10 minutes.
(X2) The density is 900 to 925 kg / m ³ .
(X3) Using a differential scanning calorimeter, the temperature was raised from 0 ° C. to 200 ° C. at a rate of 10 ° C./minute, held at 200 ° C. for 10 minutes, lowered to 0 ° C. at a rate of 10 ° C./minute, and then 0 ° C. For 10 minutes, and then at the second heating when heating to 200 ° C at a rate of 10 ° C / min, the total amount of heat of fusion observed is ΔH, When the observed heat of fusion is ΔH (T),
0.30 ≤ ΔH (80) / ΔH ≤ 0.75
0.35 ≤ ΔH (100) / ΔH ≤ 0.85, and
0.40 ≤ ΔH (120) / ΔH ≤ 0.95
Is. A substrate layer (A) is further laminated on a surface of the intermediate layer (B) opposite to the sealant layer (C) side, and at least a part of the intermediate layer (B) and the substrate layer ( Is in contact with at least part of A),
The laminate according to claim 1, wherein the sealant layer (C) contains an ethylene / α-olefin copolymer (Y) satisfying the following requirements (y0) to (y2):
(Y0) A copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms.
(Y1) The melt flow rate measured at 190 ° C. under a load of 2.16 kg is 1 to 50 g / 10 minutes.
(Y2) The density is 880 to 920 kg / m ³ .   The base material layer (A) is at least one selected from the group consisting of polyamide resin, polyester resin, polyolefin resin, polyvinylidene chloride resin, saponified ethylene-vinyl acetate copolymer, polycarbonate resin, polystyrene resin and acrylic resin. The laminate according to claim 2, comprising at least one selected from the group consisting of a film containing one kind of thermoplastic resin and a stretched product thereof, a metal foil, a ceramic vapor deposition film, paper, and a non-woven fabric.   The base material layer (A) has at least a part of the surface of the base material, and at least one adhesive selected from the group consisting of polyurethane, an isocyanate compound, a polyester, and a mixture of a polyol and an isocyanate compound and a reaction product. The laminate according to claim 2, further comprising an adhesive layer made of an agent, which is in contact with the intermediate layer (B) through the adhesive layer.   A liquid packaging bag formed from the laminate according to any one of claims 1 to 4.   A liquid-containing packaging bag comprising the liquid packaging bag according to claim 5 and a liquid or a viscous substance contained in the liquid packaging bag. A process of filling the liquid packaging bag according to claim 5 with a liquid or a viscous substance to manufacture the liquid-containing packaging bag according to claim 6,
The liquid-containing packaging bag is a liquid-containing packaging that is manufactured in a state of a sheet in which a plurality of the liquid-containing packaging bags are continuous in the longitudinal direction and at a feeding speed of the sheet in the longitudinal direction of 20 m / min or more. Bag manufacturing method.