JP2009096155A - Multi-layer laminated film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-layer laminated film excellent in the unpacking easiness when used as a lid material for container or a packaging sack, having a heat resistance susceptible to a heating process such as boiling, a retort processing, etc. excellent in the easy-to-cut possibility, and free of impairing the outside appearance caused by thread trailing at the peel part, and provide a package container using it as lid material and also a packaging sack. <P>SOLUTION: The multi-layer laminated film has a seal layer A and base material layer(s) B, the former A consisting of a mixture of high-density polyethylene and polypropylene, and on the seal layer A one or more base material layers B are laminated consisting of a block or random copolymer of ethylene-propylene, wherein the thickness of the seal layer A is 1-20 μm while the thickness of the base material layer B is 20-100 μm. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention is a multilayer laminated film mainly used for lids and packaging bags of packaging containers such as foods and chemical products in the field of soft packaging, and has a sufficient sealing property and an excellent opening property. Multi-layer laminated film that has heat resistance that can withstand heat treatment such as treatment and retort treatment, is easy to cut, and does not impair the appearance due to stringing of the peel portion, etc., and packaging that uses it as a lid It relates to containers and packaging bags.

  In recent years, packaging containers and packaging bags are required to have sufficient hermeticity for protecting and preserving contents, and are also required to be easily opened (easy peel) that can be easily opened when consumed. Various proposals have been made as packaging films having both practical sealing properties and easy opening properties.

For example, as a film for easy opening, a heat-sealable laminated film (see Patent Document 1) consisting of two layers of a blend layer of various acrylic acid copolymers and polyethylene, or a base material layer made of polypropylene A film in which a three-component blend layer of polybutene, polypropylene and polyethylene is laminated (see Patent Document 2), a multilayer film having a layer made of a mixture of a methacrylic acid copolymer and polypropylene and a polyethylene sealant layer (see Patent Document 3) ) Has been developed.
JP-A-5-212835 JP-A-6-328639 JP 2002-283513 A

  However, conventional films intended for easy opening have a high material cost, a low degree of freedom in film forming conditions (blending conditions, etc.), and heat resistance such as polybutene for the purpose of improving low temperature sealing properties. Therefore, the appearance is impaired by stringing the peel part.

  As a result of studying to solve the above problems, the present inventors have found that a multilayer laminate film having a seal layer (A) and a base material layer (B) as a multilayer laminate film having easy opening properties, heat resistance, and easy cutting properties. A base material layer made of a block or random copolymer of ethylene / propylene on a sealing layer (A) made of a mixture of 10 to 50 parts by weight of high-density polyethylene and 50 to 90 parts by weight of polypropylene. B) is laminated one or more layers, the layer thickness of the sealing layer (A) is 1 μm to 20 μm, and the layer thickness of the base material layer (B) is 20 μm to 100 μm, A multilayer laminated film was developed. Further, by laminating a packaging material selected from a stretched film, a barrier film and an aluminum foil on this multilayer laminated film, a multilayer laminated film having an oxygen barrier property and a water vapor barrier property and excellent in aesthetics can be obtained. It was.

  Since the multilayer laminated film of the present invention is excellent in heat resistance, a packaging container and a packaging bag using the multilayer film can sufficiently withstand heat treatment conditions such as boiling and retort treatment. Moreover, this packaging container and packaging bag have moderate easy-openability unlike the thing for the conventional retort. Furthermore, since there is little stringing of an opening part, it is excellent in both practicality and aesthetics.

  In addition, the multilayer laminated film of the present invention can be produced by various methods known to those skilled in the art, but is preferably produced also by an inflation film-forming method that can be produced at low cost even in the case of a small lot. Can do. The inflation film-forming method is a film-forming method suitable for the production of various types of small quantities, but has a narrow application range and can be used only for limited materials. The multilayer laminated film of the present invention is very preferable from the viewpoint of cost because such an inflation film forming method can be applied.

  The sealing layer (A) of the multilayer laminated film of the present invention is composed of incompatible high-density polyethylene and polypropylene, and among these resins, the higher component ratio forms the sea, and the lower component ratio forms the island. Take a sea-island structure.

  In the present invention, a desired cohesive peel strength can be achieved by controlling the sea-island structure by controlling the MFR (melt mass flow rate) of the resin. Moreover, by taking such a structure, this invention can reduce the cost concerning manufacture compared with the conventional easy-open film.

  Furthermore, in the multilayer laminated film of the present invention, a packaging material selected from a stretched film, a barrier film and an aluminum foil is laminated on the outermost surface of the base material layer (B) on the side opposite to the seal layer (A). By this, it becomes possible to give a further excellent gas barrier property.

The present invention will be described in detail below.
The multilayer laminated film of the present invention has a seal layer (A) and a base material layer (B) laminated thereon.

<1> Seal layer (A)
Hereinafter, the resin names used in the present invention are those commonly used in the industry. In the present invention, the density was measured according to “JIS K 7112”.
(1) High-density polyethylene constituting the seal layer (A) In the present invention, polyethylene includes ethylene homopolymer and ethylene and other α-olefins (for example, propylene, 1-butene, 1-pentene, 1-hexene). , 1-octene and the like) or random copolymers.
The high density polyethylene constituting the sealing layer (A) has a density of 0.945 to 0.965 g / cm ³ , more preferably 0.950 to 0.955 g / cm ³ , and MFR (190 ° C.). Is a resin having a relatively high melt viscosity, which is 1 to 7 g / 10 min, more preferably 1 to 4 g / 10 min. As a result, fuzzing at the time of peeling of the cover material can be prevented, and the appearance after peeling becomes beautiful.

In the above, if the density is less than 0.945 g / cm ³ , stringing tends to occur, and if it exceeds 0.965 g / cm ³ , an unmelted material may be produced during film formation, and the appearance of the film There is a risk of failure.
And when MFR (190 degreeC) is less than 1 g / 10min, since flowability falls, manufacture becomes difficult, and also the nonuniformity which raise | generates a compatibility defect with the high MFR polypropylene and is visible. Since it occurs, it is not preferable. On the other hand, if it exceeds 7 g / 10 minutes, the difference from the MFR of polypropylene disappears, so that the degree of mutual dispersion increases and the desired easy-openability cannot be obtained, which is not preferable. Here, MFR (190 ° C.) was measured according to “JIS K6922”.
Suitable high-density polyethylene used in the present invention includes, for example, Hi-Zex 3300F manufactured by Prime Polymer Co., Ltd. and Novatec HJ360 and HJ362N manufactured by Nippon Polyethylene Co., Ltd.

(2) Polypropylene constituting the seal layer (A) In the present invention, polypropylene includes a propylene homopolymer and a block or random copolymer of propylene and another α-olefin.
As the polypropylene constituting the sealing layer (A), a resin having a density of 0.9 to 0.91 g / cm ³ and an MFR (230 ° C.) of 5 to 30 g / 10 min is used. In order to obtain an appropriate seal strength, an ethylene / propylene random copolymer is particularly preferable. The block copolymer may have a cohesive fracture strength that is too high to obtain good easy-openability.

In the above, when MFR (230 ° C.) is less than 5 g / 10 minutes, fluidity is close to that of low-MFR high-density polyethylene, so that it is in a finely dispersed state, so that appropriate easy-openability cannot be obtained. Moreover, when MFR (230 degreeC) exceeds 30 g / 10min, since it is highly fluid, it cannot form into a film by an inflation film forming method. Here, MFR (230 ° C.) was measured according to “JIS K6921”.
Examples of suitable polypropylene for use in the present invention include ethylene / propylene random copolymer (J235T) manufactured by Prime Polypro Co., Ltd. and Novatec FL03H manufactured by Nippon Polypro Co., Ltd.

(3) Blend ratio The blend ratio of the high-density polyethylene and polypropylene in the seal layer (A) is preferably composed of 10 to 50 parts by weight of high-density polyethylene and 50 to 90 parts by weight of polypropylene. The blend ratio can be changed according to the adhesive strength.
If the ratio of polypropylene is higher than the above range, the adhesive strength becomes too high and good easy-openability cannot be obtained, and if the ratio is low, sufficient adhesive strength cannot be obtained, and the sealing property as a packaging container or packaging bag Is not satisfied.

<2> Base material layer (B)
The base material layer (B) of the multilayer laminated film of the present invention not only contributes to easy opening in combination with the sealing layer (A), but also serves as a lid for a packaging container or as a packaging bag. Strength, heat resistance that can withstand heat treatment such as boil and retort treatment, and film formation stability are also required. As a resin that satisfies these requirements and is preferable in terms of cost, an ethylene / propylene block or a random copolymer is used.
As for a base material layer (B), 1 layer or 2 layers or more can be laminated | stacked as needed.

  Suitable ethylene / propylene block or random copolymers used in the present invention include, for example, ethylene / propylene block copolymers (PF380A, PC540R and FX4E) manufactured by Sun Allomer Co., Ltd., ethylene / propylene block copolymers manufactured by Nippon Polypro Co., Ltd. A propylene block copolymer (FW4BT) etc. are mentioned.

<3> Packaging material One or more layers of various packaging materials, for example, stretched films, barrier films, and aluminum foils can be appropriately laminated on the surface of the base material layer of the multilayer laminated film of the present invention. . For example, the multilayer laminated film of the present invention in which a packaging material is laminated as follows is preferable.
(I) A multilayer laminated film in which a stretched film is laminated on the outermost surface of the base material layer (B) on the side opposite to the seal layer (A), and then a barrier film is laminated.
(Ii) A multilayer laminated film in which a barrier film is laminated on the outermost surface of the base material layer (B) on the side opposite to the seal layer (A), and then a stretched film is laminated.
(Iii) A multilayer laminated film in which a stretched film is laminated on the outermost surface of the base material layer (B) on the side opposite to the seal layer (A), then an aluminum foil is laminated, and then the stretched film is laminated.
(Iv) A multilayer laminated film in which an aluminum foil is laminated on the outermost surface of the base material layer (B) on the side opposite to the seal layer (A), and then one or more stretched films are laminated.

  In the present invention, the “stretched film” refers to a film made of polyester such as polyethylene terephthalate (PET), polybutylene terephthalate, 6-naphthalate, polyamide such as nylon 6, nylon 66, polyvinyl chloride, polyvinyl alcohol, and polycarbonate. . Particularly preferred stretched films include stretched films made of polyester (polyethylene terephthalate), polyamide (nylon 6, nylon 66, nylon 6-66), etc., which are excellent in transparency, mechanical strength and packaging suitability. By laminating various stretched films on the multilayer laminated film of the present invention, the physical strength of the film can be improved.

In the present invention, the “barrier film” refers to, for example, an alumina deposited film, a silica deposited film, and an acrylic resin coating film.
An alumina vapor-deposited film and a silica vapor-deposited film are films in which alumina or silica is vapor-deposited on one side of a PET or nylon film to provide a barrier layer, and exhibit excellent oxygen barrier properties and water vapor barrier properties.

The acrylic resin coating film is a film in which an acrylic resin is coated on one side of a PET film to provide a barrier layer, and exhibits excellent oxygen barrier properties. Since the barrier layer is made of a resin, the oxygen barrier ability is maintained without breaking the barrier layer even when the film is bent. Examples of the acrylic resin coating film suitable for use in the present invention include Besera manufactured by Kureha Corporation.
The packaging material as described above can be laminated by, for example, a dry lamination method, a solventless lamination method, an extrusion lamination method, a coextrusion lamination method, or the like.

  If desired, it is possible to prevent the film from sagging after heat treatment by laminating a stretched film exhibiting heat shrinkability on the outermost surface of the base material layer (B). A stretched nylon film or a vapor-deposited stretched nylon film is used as the stretched film exhibiting such heat shrinkability. Since these films have a hydrogen bonding part, they can be stretched at the time of film formation as compared with PET films that are conventionally used as stretched films. When heated above the glass transition point, they have stronger shrinkage than PET films. Show. Accordingly, a beautiful appearance can be maintained without sagging of the film even after the boil treatment and the retort treatment. However, when the shrinkage ratio of MD (film flow direction) and TD (flow direction perpendicular to the nylon film) is less than 0.5% when heated in hot water at 100 ° C. for 5 minutes, boil treatment Later, the film sags due to internal pressure, and when the shrinkage rate of MD and TD is larger than 4.0%, the vapor deposition barrier layer is destroyed due to the shrinkage, and sufficient oxygen and water vapor barrier properties cannot be obtained.

  Examples of the “stretched nylon film” suitable for use in the present invention include Harden N1130, N1102, and N1200 manufactured by Toyobo Co., Ltd. and Emblem ONU, ONMB, and ONM manufactured by Unitika Co., Ltd. Examples of the “CVD-silica-deposited stretched nylon film” include IB-ON manufactured by Dai Nippon Printing Co., Ltd. These films are particularly preferably laminated by a dry laminating method because they are inexpensive and can be produced without reducing the speed of the line.

<4> Layer Thickness Regarding the sealing layer (A), the layer thickness is 20 μm or less, preferably 10 μm or less. When it exceeds 20 μm, the release layer (aggregated release layer) becomes dirty, and the release surface is inferior in beauty. Regarding the base material layer (B), a layer thickness of 20 μm to 100 μm is preferable from the viewpoint of easy cutting.

<5> Physical Properties Next, factors in setting physical properties required for the multilayer laminated film of the present invention will be described.
(1) Cohesive failure strength The easy-openability or the cohesive failure strength of the multilayer laminated film of the present invention is controlled by changing the blending ratio of high-density polyethylene and polypropylene used for the seal layer (A).

(2) Gas barrier property In order to suppress the quality deterioration of the contents (food, etc.), a packaging material having oxygen and / or water vapor barrier property may be further laminated on the multilayer laminated film of the present invention.
The multilayer laminated film of the present invention is 2.0 cc / m ² · day ·, as a numerical value obtained by a method according to JIS K 7126 regarding oxygen permeability by individually or optionally further laminating an appropriate packaging material. Excellent oxygen barrier property of atm or less can be shown, and regarding water vapor permeability, excellent water vapor barrier property of 3.0 g / m ² · day or less is obtained as a numerical value obtained by a method according to JIS K 7129. be able to.

<6> Configuration of Multilayer Laminate Film Next, the configuration of the multilayer laminate film of the present invention will be described with reference to the example shown in FIG. FIG. 1 shows a base material of a packaging material comprising a laminated adhesive layer laminated on a multilayer laminated film having a sealing layer (A) and a base material layer (B) according to the present invention, and comprising a stretched film or a barrier film thereon. And a laminate adhesive layer printed as necessary is further laminated thereon, and a packaging material substrate made of a stretched film or a barrier film is laminated thereon.

<7> Packaging container The multilayer laminated film of the present invention is used for a sealant film for a lid of a packaging container. Specifically, heat sealing is performed in a state where the seal layer (A) is overlapped with an opening of a container formed of polypropylene, and the seal layer (A) is agglomerated and peeled at the time of opening.

<8> Packaging Bag The multilayer laminated film of the present invention can be preferably used as a packaging bag. The packaging bag made of the multilayer laminated film of the present invention has excellent easy-openability and gas barrier properties.
(1) Bag Making Such a packaging bag is formed by folding the multilayer laminated film of the present invention so that the surfaces of the sealing layer (A) face each other, and the end portion thereof is a side seal type or a flat bottom seal type. It can be manufactured in various forms by heat-sealing in accordance with the desired heat seal shape. Alternatively, the two multilayer laminated films of the present invention may be formed by overlapping the two layers so that the surface of the sealing layer (A) faces the inside of the packaging bag and heat-sealing the end portions. Moreover, the 1st film which consists of a multilayer laminated | multilayer film of this invention can also be overlap | superposed with one arbitrary 2nd film, and can be bag-formed similarly. This is because the multilayer laminated film of the present invention can achieve an appropriate adhesive strength even when it is heat-sealed with a surface other than the sealing layer, for example, made of only polypropylene. .

As the second film, for example, the following multilayer laminated film can be suitably used:
(I) A multilayer laminated film obtained by laminating a stretched film on the surface of a polypropylene film and then laminating a barrier film;
(Ii) a multilayer laminated film in which a barrier film is laminated on the surface of a polypropylene film and then a stretched film is laminated;
(Iii) A multilayer laminated film obtained by laminating a stretched film on the surface of a polypropylene film, then laminating an aluminum foil, and then laminating the stretched film;
(Iv) A multilayer laminated film obtained by laminating an aluminum foil on the surface of a polypropylene film and then laminating one or more stretched films.

In this case, in the packaging bag, the surface of the sealing layer (A) of the first film made of the multilayer laminated film of the present invention is overlaid so as to face the surface of the polypropylene film of the second film, and the ends are heat-sealed. It is manufactured by doing. The stretched film of the second film is, for example, a polyethylene terephthalate film or a stretched nylon film. Moreover, the barrier film of a 2nd film is an alumina vapor deposition film, a silica vapor deposition film, or an acrylic acid resin coating film, for example.
The heat fusion can be performed by a known method such as heat sealing or impulse sealing.

  In actual work, an insertion port for inserting contents is left, and the other peripheral edge is made by heat-sealing. Then, the contents are filled and the insertion port is closed by heat sealing. At the time of opening, cohesive failure of the sealing layer (A) occurs on the fused surface, and a beautiful opened surface is obtained.

(2) Seal shape of opening part The packaging bag of this invention can provide the opening part of various aspects according to the use. In that case, moderate easy-openability can be provided by controlling MFR of resin which comprises a seal layer (A) according to the seal shape of an opening part.
FIG. 2 is a view showing an embodiment of the packaging bag of the present invention. In FIG. 2, the opening is heat-sealed in the shape of a lip that protrudes outward from the bag, and a flange is provided on the periphery thereof. When opening the packaging bag, the top of the shed serves as a peeling start point, and thereafter, the action point of detachment moves toward the bottom of the shed. Compared with the case where the opening is heat-sealed linearly along the direction orthogonal to the opening direction, the force required for peeling is dispersed by heat-sealing in the shape of the mouth. Therefore, it is possible to obtain a packaging bag that can be opened more easily while maintaining sufficient sealing performance.

  The shed shape is an inverted V shape consisting of two straight lines or curves that are not parallel. When heat-sealing along the two lines, the force required for opening can be adjusted by adjusting the seal width. In the present invention, from the viewpoint of hermeticity and easy opening, the sum of the seal widths measured along the direction perpendicular to the opening direction in the portion excluding the intersection of the two lines is 5 to 20 mm. Preferably, it is 6-12 mm.

  Moreover, in this invention, you may heat-seal an opening part double as FIG. That is, the opening of the film can be heat-sealed, and then further heat-sealed at an appropriate interval from the heat-sealed line. Thereby, even if it is a case where it is mischievous, the sealing performance of a packaging bag can be maintained.

The present invention will be described more specifically with reference to examples.
[Example 1]
(1) Seal layer (A)
High-density polyethylene (Hi-Zex 3300F manufactured by Prime Polymer Co., Ltd .: density = 0.950 g / cm ³ , MFR (190 ° C.) = 1.1 g / 10 min), 30 parts by weight of ethylene / propylene random copolymer (Nippon Polypro Novatec FL02C manufactured by Co., Ltd .: 70 parts by weight of density = 0.9 g / cm ³ and MFR (230 ° C.) = 18 g / 10 minutes) were sufficiently kneaded to prepare a resin composition for the seal layer (A).

(2) Base material layer (B)
Resin for base layer (B) comprising 100 parts by weight of ethylene / propylene block copolymer (PF380A manufactured by Sun Allomer Co., Ltd .: density = 0.90 g / cm ³ , MFR (190 ° C.) = 1.0 g / 10 min) A composition was prepared.
A multi-layer laminated film (sealing layer (A) 10 μm / base layer (B) 40 μm) having a total thickness of 50 μm was produced using a top-blown air-cooled inflation coextrusion film forming machine.

[Example 2]
(1) Seal layer (A)
30 parts by weight of high-density polyethylene (Novatec HJ360 manufactured by Nippon Polyethylene Co., Ltd .: Density = 0.951 g / cm ³ , MFR (190 ° C.) = 5.5 g / 10 min), ethylene / propylene random copolymer (Nippon Polypro) Novatec FL02C manufactured by Co., Ltd .: 70 parts by weight of density = 0.9 g / cm ³ and MFR (230 ° C.) = 18 g / 10 minutes) were sufficiently kneaded to prepare a resin composition for the seal layer (A).

(2) Base material layer (B)
For base material layer (B) comprising 100 parts by weight of ethylene / propylene block copolymer (FW4BT manufactured by Nippon Polypro Co., Ltd .: density = 0.90 g / cm ³ , MFR (230 ° C.) = 6.5 g / 10 min) A resin composition was prepared.
A multi-layer laminated film (sealing layer (A) 5 μm / base material layer (B) 45 μm) having a total thickness of 50 μm was produced using a top-blown air-cooled inflation coextrusion film forming machine.

[Example 3]
(1) Seal layer (A)
High-density polyethylene (Novatec HJ362N manufactured by Nippon Polyethylene Co., Ltd .: Density = 0.953 g / cm ³ , MFR (190 ° C.) = 5.0 g / 10 min) and 40 parts by weight of ethylene / propylene random copolymer (Nippon Polypropylene) Novatec FL03A manufactured by Co., Ltd .: 60 parts by weight of density = 0.9 g / cm ³ and MFR (230 ° C.) = 20 g / 10 minutes) were sufficiently kneaded to prepare a resin composition for the seal layer (A).

(2) Base material layer (B)
Resin for base layer (B) comprising 100 parts by weight of ethylene / propylene block copolymer (PC540R manufactured by Sun Allomer Co., Ltd .: density = 0.90 g / cm ³ , MFR (230 ° C.) = 5.0 g / 10 min) A composition was prepared.
A multi-layer laminated film (sealing layer (A) 5 μm / base material layer (B) 45 μm) having a total thickness of 50 μm was produced using a top-blown air-cooled inflation coextrusion film forming machine.

[Example 4]
(1) Seal layer (A)
High-density polyethylene (Prime Polymer Co., Ltd. Hi-Zex 3300F: density = 0.950 g / cm ³ , MFR (190 ° C.) = 1.1 g / 10 min), 30 parts by weight, ethylene-propylene random copolymer (Prime Polypro Co., Ltd. J235T: Density = 0.90 g / cm ³ , MFR (230 ° C.) = 15 g / 10 min) was sufficiently kneaded to prepare a resin composition for the seal layer (A).

(2) Base material layer (B)
Resin for base layer (B) comprising 100 parts by weight of ethylene / propylene block copolymer (FX4E manufactured by Sun Allomer Co., Ltd .: density = 0.90 g / cm ³ , MFR (230 ° C.) = 5.3 g / 10 min) A composition was prepared.
A multi-layer laminated film (sealing layer (A) 5 μm / base material layer (B) 45 μm) having a total thickness of 50 μm was produced using a top-blown air-cooled inflation coextrusion film forming machine.

[Example 5]
Corona treatment is applied to the surface of the base material layer (B) opposite to the sealing layer (A) of the multilayer laminated film produced in Example 1, and a two-component curable urethane adhesive (main agent: polyester polyol, cured) is applied to the surface. Agent: Aliphatic isocyanate) is coated, and a CVD-silica vapor-deposited stretched nylon film (Dai Nippon Printing Co., Ltd. IB-ON-UB (single-sided corona treatment): thickness 15 μm) is laminated, and then a biaxially stretched nylon film (Emblem NX (double-sided corona treatment) manufactured by Unitika Ltd .: thickness 15 μm) was laminated. The obtained multilayer laminated film has a structure of (seal layer (A) / base material layer (B) / DL / CVD method silica-deposited stretched nylon film layer / DL / biaxially stretched nylon film layer). Means drug part).

[Examples 6 to 8]
A packaging material was laminated in the same manner as in Example 5 using the multilayer laminated films produced in Examples 2 to 4, respectively.

[Example 9]
Corona treatment is applied to the surface of the base material layer (B) opposite to the seal layer (A) of the multilayer laminated film produced in Example 1, and the two-component curable urethane adhesive (main agent: polyester polyol, curing agent) is applied to the surface. : Aliphatic isocyanate), stretched nylon film (Unitika Co., Ltd. biaxially stretched nylon film [emblem NX] (double-sided corona treatment): thickness 15 μm) is laminated, and then CVD silica vapor deposition stretched PET film ( IB-PET-RB (single-sided corona treatment) manufactured by Dai Nippon Printing Co., Ltd. (thickness: 12 μm) was laminated. The obtained multilayer laminated film has a structure of (seal layer (A) / base material layer (B) / DL / stretched nylon film layer / DL / CVD-silica-deposited stretched PET film layer).

[Example 10]
Corona treatment is applied to the surface of the base material layer (B) opposite to the seal layer (A) of the multilayer laminated film produced in Example 2, and a two-component curable urethane adhesive (main agent: polyester polyol, cured) is applied to the surface. Agent: Aliphatic isocyanate) is applied, and stretched nylon film (biaxially stretched nylon film [Emblem NX] (double-side corona treatment): 15 μm thick) manufactured by Unitika Ltd.] is laminated, then acrylic resin coating film (Kureha) Co., Ltd. Besera ET-R (single-sided corona treatment: 13 μm thick) was laminated. The obtained multilayer laminated film has a structure of (seal layer (A) / base material layer (B) / DL / stretched nylon film layer / DL / Besela ET-R).

[Example 11]
Corona treatment is applied to the surface of the base material layer (B) opposite to the seal layer (A) of the multilayer laminated film produced in Example 3, and a two-component curable urethane adhesive (main agent: polyester polyol, cured) is applied to the surface. Agent: Aliphatic Isocyanate), CVD Silica Vaporized Stretched Nylon Film (Dai Nippon Printing Co., Ltd. IB-ON (double-sided corona treatment): 15 μm thick) is laminated, then Besera ET-R (single-sided corona treatment) : 13 μm thick). The obtained multilayer laminated film has a structure of (seal layer (A) / base material layer (B) / DL / stretched nylon film layer / DL / Besela ET-R).

[Example 12]
Using the multilayer laminated film produced in Example 4, the packaging material was laminated in the same manner as in Example 9.

[Examples 13 to 16]
Each of the multilayer laminated films produced in Examples 5 to 8 was used as a lid for a cup-shaped container (diameter 74φ, flange width 5 mm, volume 120 cc) made of polypropylene, from a flat seal to a seal temperature of 190 ° C., 3 kg / cm ² , The sample was heat sealed under conditions of 1 second to fill the cup with water. Then, it was subjected to a retort treatment at 121 ° C. for 30 minutes in a retort kettle. After the retort treatment, it was stored at room temperature for 24 hours, the appearance was confirmed, and the seal strength, the oxygen permeability of the lid, and the water vapor permeability were measured. Even after the retort treatment, there was no slack in the lid. Moreover, high oxygen barrier property and water vapor barrier property, and appropriate seal strength were shown.

[Example 17]
Two multilayer laminated films produced in Example 9 were overlapped so that the surfaces of the sealing layer (A) face each other, and the ends were heat-sealed under conditions of a sealing temperature of 190 ° C., 1 kg / cm ² and 1 second. A packaging bag in which the opening is heat-sealed in a mouth shape and a packaging bag in which the opening is heat-sealed in a mouth shape are created. Of these, 180 cc of water was sealed in a single heat-sealed packaging bag and subjected to a retort treatment at 121 ° C. for 30 minutes in a retort kettle. After the retort treatment, it was stored at room temperature for 24 hours, the appearance was confirmed, and the seal strength, oxygen permeability of the packaging bag, and water vapor permeability were measured. There was no water leakage in the packaging bag after the retort treatment. Moreover, high oxygen barrier property and water vapor barrier property, and appropriate sealing strength (opening mouth strength) were exhibited.

[Example 18]
Two multilayer laminated films produced in Example 10 were laminated so that the surfaces of the sealing layer (A) face each other, and the ends were heat-sealed under the conditions of a sealing temperature of 190 ° C., 1 kg / cm ² and 1 second. A packaging bag in which the opening is heat-sealed in a mouth shape and a packaging bag in which the opening is heat-sealed in a mouth shape are created. Of these, a single heat-sealed packaging bag was used, and a commercially available sausage (50 g) was enclosed therein, and subjected to a retort treatment at 121 ° C. for 30 minutes in a retort kettle. After the retort treatment, it was stored at room temperature for 24 hours, the appearance was confirmed, and the seal strength, oxygen permeability of the packaging bag, and water vapor permeability were measured. There was no content leakage in the packaging bag after the retort treatment. Further, it exhibited high oxygen barrier properties and water vapor barrier properties, and appropriate seal strength (opening mouth strength).

[Example 19]
A packaging bag made of the multilayer laminated film (first film) of Example 11 and the second film produced as follows was produced.
a) Production of second film (1) Layer (X)
100 parts by weight of ethylene / propylene block copolymer (manufactured by Nippon Polypro Co., Ltd. (BC6CB): density = 0.9 g / cm ³ , MFR (230 ° C.) = 2.5 g / 10 min) is sufficiently kneaded, A resin composition for layer (X) was prepared.

(2) Layer (Y)
100 parts by weight of ethylene / propylene block copolymer (manufactured by Sun Allomer Co., Ltd. (PF380A): density = 0.9 g / cm ³ , MFR (230 ° C.) = 1.1 g / 10 min) was sufficiently kneaded and layered A resin composition for (Y) was prepared.
A multi-layer laminated film (layer (X) 5 μm / layer (Y) 45 μm) having a total thickness of 50 μm was produced using a top-blown air-cooled inflation coextrusion film forming machine.
Corona treatment is applied to the surface of the layer (Y) opposite to the seal layer (X), a two-component curable urethane adhesive (main agent: polyester polyol, curing agent: aliphatic isocyanate) is applied to the surface, and stretched nylon Film (Unitika Co., Ltd. biaxially stretched nylon film [Emblem NX] (double-sided corona treatment): 15 μm thick) is laminated, then aluminum foil (Toyo Aluminum Co., Ltd .: 7 μm thick) is laminated, then Then, a stretched PET film (T4102 (single-sided corona treatment: thickness 12 μm) manufactured by Toyobo Co., Ltd.) was laminated. The obtained multilayer laminated film has a structure of (layer (X) / layer (Y) / DL / stretched nylon film layer / DL / aluminum foil / DL / stretched PET film layer).

b) Production of packaging bag The multilayer laminated film produced in Example 11 was used as the first film, and the surface of the sealing layer (A) was superposed so as to face the surface of the layer (X) of the second film, The end part was heat-sealed at a seal temperature of 190 ° C. and 1 kg / cm ² for 1 second, and a packaging bag with an opening part heat-sealed in a mouth shape and a double-sealed packaging bag were prepared. . Of these, a single heat-sealed packaging bag was used, and a commercially available sausage (50 g) was enclosed therein, and subjected to a retort treatment at 121 ° C. for 30 minutes in a retort kettle. After the retort treatment, it was stored at room temperature for 24 hours, the appearance was confirmed, and the seal strength, the oxygen permeability and the water vapor permeability of the first film (Example 11) of the packaging bag were measured. There was no content leakage in the packaging bag after the retort treatment. Further, the first film (Example 11) exhibited high oxygen barrier property and water vapor barrier property, and appropriate seal strength (opening mouth strength).

[Example 20]
Similar results were obtained in the same manner as in Example 19 except that the multilayer laminated film of Example 12 was used as the first film.

[result]
The seal strength, oxygen permeability, and water vapor permeability measured in the above examples are summarized in Table 1.
These physical properties were measured as follows.
(1) Layer thickness: Measured with a μ-meter manufactured by SONY Corporation.
(2) Oxygen permeability: Measured using a measuring instrument of OXTRAN (OXTRAN 2/20, manufactured by MOCON, USA) under conditions of a temperature of 23 ° C. and a humidity of 90% RH.
(3) Water vapor permeability: Measured under the conditions of a temperature of 40 ° C. and a humidity of 90% RH using a measuring instrument of PERMATRAN (manufactured by MOCON, USA).
(4) Seal strength of Examples 13 to 19: Sealed from a flat seal to a polypropylene cup under conditions of a seal temperature of 190 ° C., 3 kg / cm ² and 1 second. A strip test piece having a width of 15 mm was cut out from the tensile tester, and a tensile test was performed at 300 mm / min.
(5) Seal strength of Examples 17 to 20: A strip-shaped test piece having a width of 15 mm was cut out from the heat seal portion of the packaging bag, and a tensile test was performed at 300 mm / min.

  Examples 13 to 20 all showed suitable seal strength and excellent easy-openability. Moreover, all showed very low oxygen permeability and water vapor permeability, and thus had excellent gas barrier properties.

It is sectional drawing which shows the layer structure of the cover material (multilayer laminated film + packaging material) using the multilayer laminated film of this invention. It is a figure which shows one Embodiment of the packaging bag using the multilayer laminated film of this invention. It is a figure which shows one Embodiment of the packaging bag using the multilayer laminated film of this invention. It is a figure which shows one Embodiment of the packaging bag using the multilayer laminated film of this invention.

Claims (18)

  A multilayer laminated film having a sealing layer (A) and a base material layer (B), on the sealing layer (A) comprising a mixture of 10 to 50 parts by weight of high-density polyethylene and 50 to 90 parts by weight of polypropylene, The base material layer (B) made of an ethylene / propylene block or a random copolymer is laminated one or more layers, and the layer thickness of the sealing layer (A) is 1 μm to 20 μm. A multilayer laminated film, wherein the layer thickness of (B) is 20 μm to 100 μm.   The multilayer laminated film according to claim 1, wherein the polypropylene constituting the sealing layer (A) is an ethylene / propylene random copolymer.   The multilayer laminated film of Claim 1 or 2 whose MFR (190 degreeC) of the high density polyethylene which comprises a sealing layer (A) is 1-7 g / 10min.   The multilayer laminated film according to any one of claims 1 to 3, wherein an MFR (230 ° C) of polypropylene constituting the seal layer (A) is 5 to 30 g / 10 minutes.   1 or 2 or more layers of a packaging material selected from a stretched film, a barrier film and an aluminum foil are laminated on the outermost surface of the base material layer (B) on the side opposite to the sealing layer (A). 5. The multilayer laminated film according to any one of 4 above.   The multilayer laminated film according to claim 5, wherein a stretched film is laminated on the outermost surface of the base material layer (B) opposite to the seal layer (A), and then a barrier film is laminated.   The multilayer laminated film according to claim 5, wherein a barrier film is laminated on the outermost surface of the base material layer (B) opposite to the seal layer (A), and then a stretched film is laminated.   The multilayer laminate according to claim 5, wherein a stretched film is laminated on the outermost surface of the base material layer (B) on the side opposite to the seal layer (A), then an aluminum foil is laminated, and then the stretched film is laminated. the film.   The multilayer laminated film according to claim 5, wherein an aluminum foil is laminated on the outermost surface of the base material layer (B) on the side opposite to the seal layer (A), and then one or more stretched films are laminated. .   The multilayer film according to any one of claims 5 to 9, wherein the stretched film is a polyethylene terephthalate film or a stretched nylon film.   The multilayer laminated film according to any one of claims 5 to 7, wherein the barrier film is selected from an alumina vapor-deposited film, a silica vapor-deposited film, and an acrylic resin coating film. The numerical value obtained by the method in accordance with JIS K 7126 is 2.0 cc / m ² · day · atm or less, and the water vapor transmission rate is 3. in the method obtained in accordance with JIS K 7129. The multilayer laminated film according to any one of claims 1 to 11, which is 0 g / m ² · day or less.   The multilayer laminated film according to any one of claims 1 to 12, wherein the multilayer laminated film is for retort use.   It is a packaging container which uses the multilayer laminated film of any one of Claims 1-13 as a lid | cover material, Comprising: The sealing layer (A) of this lid | cover material touches the opening part of the container formed with the polypropylene. A packaging container which is heat-sealed in a state where it is overlaid on the lid, and the sealing layer (A) of the lid material is agglomerated and peeled when opened.   A packaging bag in which the multilayer laminated film according to any one of claims 1 to 13 is folded so that the surfaces of the sealing layer (A) face each other, and the ends are heat-sealed.   A packaging bag in which two multilayer laminated films according to any one of claims 1 to 13 are overlapped so that the surfaces of these sealing layers (A) face each other and the ends are heat-sealed. The 1st film which consists of a multilayer lamination film of any 1 paragraph of Claims 1-13,
(I) A multilayer laminated film obtained by laminating a stretched film on the surface of a polypropylene film and then laminating a barrier film;
(Ii) a multilayer laminated film in which a barrier film is laminated on the surface of a polypropylene film and then a stretched film is laminated;
(Iii) A multilayer laminated film obtained by laminating a stretched film on the surface of a polypropylene film, then laminating an aluminum foil, and then laminating the stretched film;
(Iv) A multilayer laminated film obtained by laminating an aluminum foil on the surface of a polypropylene film and then laminating one or more stretched films;
A packaging bag in which any one of the second films selected from the above and the sealing film (A) of the first film are overlapped so that the surface of the second film faces the surface of the polypropylene film of the second film, and the ends are heat-sealed. .   The stretched film of the second film is a polyethylene terephthalate film or a stretched nylon film, and the barrier film of the second film is selected from an alumina deposited film, a silica deposited film, and an acrylic resin coating film. Multi-layer laminated film.

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