JP2003145698A - Laminate for packaging food - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminate for packaging food extremely excellent in linear cutting properties and also excellent in cold impact resistance and heat seal strength. SOLUTION: In a food packaging bag obtained by forming the laminate 10, which comprises a heat sealable film 3 comprising a resin composition based on a propylene/ethylene block copolymer resin and a substrate film 1, into a bag shape so that the heat sealable film 3 becomes inside, the heat sealable film 3 comprises a layer 31 on the side of the laminate and a layer 32 coming into contact with food. The laminate for packaging food comprises a composition comprising a propylene/ethylene block copolymer (1) being a first component and an ethylene/butene-1 copolymer and/or low density linear polyethylene being a second component and having a predetermined melt flow rate.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a laminated body for food packaging, and more specifically, to a heat-sealing film and a base material which are mainly composed of a propylene-ethylene block copolymer and have improved heat-sealability and tearability. The present invention relates to a laminate for food packaging, which is a laminate comprising a material film and is useful for producing a retort food packaging bag.

[0002]

BACKGROUND OF THE INVENTION Conventionally, a laminated film using a laminate comprising a heat-sealable film made of a propylene-ethylene block copolymer and a base film such as a polyethylene terephthalate film or a polyamide film is known as a retort food packaging bag (hereinafter referred to as a bag). Also known as "retort pouch"). In general,
When the contents are to be sealed, the container is filled with the contents and then heat-sealed. At that time, if the heat-sealing temperature is high, the container is deformed, the heat-sealing portion becomes thin, and leakage of the contents occurs, so a heat-sealing film capable of heat-sealing at a low temperature is required. . The propylene-ethylene block copolymer is
Since the melting point is around 160 ° C., fusion and deformation of the films during retort sterilization are less likely to occur, and there are few extracted transfer components to the contents, so it is widely known as a heat-sealable film provided on the inner surface of the retort pouch. There is. On the other hand, when ingesting or using the contents, the easy-to-tear property allows the contents to be easily torn and the contents can be taken out easily by hand. From this point of view, it is considered to be an important function required for packaging laminate materials in the future.

[0003]

However, the polyethylene terephthalate film and the polyamide film, which are known as the above-mentioned laminate materials, require a stretching process step during production, as compared with general laminate materials, Moreover, since a special material is added, the economy is poor. Further, polyethylene terephthalate film, because the polyamide film has a property that the orientation is not completely parallel to the film direction, when tearing and opening the bag, even if you try to tear in the lateral direction, the tearing direction shifts in the middle,
It has the drawback of being torn in an oblique direction. Further, the heat-sealable film used for retort food packaging, the propylene-ethylene block copolymer itself is a difficult-to-tear material, polyethylene terephthalate film which is an easily tearable film, laminated with a polyamide film and a heat-sealable film. Even if it is made into a body, it cannot satisfy the easy tearability sufficiently.
In addition, since the retort food packaging bag uses a method of packing and distributing the contents, further, after filling the contents and sterilizing by heating, an appropriate sealing strength is required to prevent leakage of the contents. Has been. Therefore, conventionally, a heat-sealable film made of a propylene-ethylene block copolymer is not intentionally examined for easy tearability.

[0004]

Therefore, the present inventors have found the present invention as a result of earnest research in order to solve the above problems. The present invention provides a laminate comprising a heat-sealing film made of a resin composition containing at least a propylene-ethylene block copolymer resin as a main component and a heat-resistant resin film, so that the heat-sealing film is on the inside. In the laminate for food packaging formed in a bag shape, the resin composition containing the propylene-ethylene block copolymer resin as a main component comprises a layer (A) on the laminate side and a layer (B) in contact with food. The layer (A) on the laminate side is an ethylene-butene containing propylene-ethylene block copolymer (1) 70 to 90% by weight as a first component and butene-1 as a second component in an amount of 15% by weight or more. -1 copolymer and / or LLDPE of 10
The propylene-ethylene block copolymer (1) as the first component contains propylene homopolymer or a propylene-ethylene block copolymer (I) having an ethylene content of 2% by weight or less. )
85-95% by weight and ethylene content 20-95% by weight
Ethylene-propylene copolymer block (II)
It is composed of 15 wt% and has a melt flow rate (230
C., load 2.16 kg) is 1.0 to 4.0 g / 10 minutes, and the layer (B) in contact with the food has a propylene-ethylene block copolymer (1) 90 to 90 as the first component.
A laminate for food packaging, which comprises 100% by weight and an ethylene-butene-1 copolymer containing 15% by weight or more of butene-1 as a second component and / or 0 to 10% by weight of LLDPE. It is related to.

In the above, the resin composition containing the propylene-ethylene block copolymer resin as a main component is
The layer (B) in contact with the food is the propylene-ethylene block copolymer (1) 25-
Ethylene-butene-1 copolymer 5 to 30 containing 70% by weight and 15% by weight or more of butene-1 as the second component
% By weight and 25 to 50% by weight of the propylene-ethylene block copolymer (2) as the third component,
The propylene-ethylene block copolymer (2) as a component comprises a propylene homopolymer or a propylene block (I) of 65 to 85% by weight, which is composed of a propylene-ethylene copolymer having an ethylene content of 2% by weight or less, and an ethylene content. Of 20 to 95% by weight of ethylene-propylene copolymer block (II) and 15 to 35% by weight, and a melt flow rate (230 ° C., load 2.16 kg) of 0.5 to 1.5 g / 10 minutes. It is also possible to provide a laminated body for food packaging characterized by the above. Further, the heat-sealable film made of the resin composition containing the propylene-ethylene block copolymer resin as a main component has a thickness of 50 to 50.
The total layer thickness of 100 μm, and the layer thickness ratio of the layer (A) on the laminating side and the layer (B) in contact with the food is 9: 1 to 3: 7. The food packaging laminate according to claim 2 can also be provided.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below.

FIG. 1 is a sectional view showing an example of a laminated body for food packaging of the present invention. The food packaging laminate 10 comprises a base film 1 and a heat-sealable film 3 made of an unstretched polypropylene film containing propylene-ethylene block copolymer resin as a main component, and an adhesive layer 2
It is laminated through. The heat-sealable film 3 is composed of a laminated film in which a laminate-side layer 31 having easy tearability and a layer 32 in contact with food are laminated.

FIG. 2 is a sectional view showing an example of a laminated body for food packaging according to another aspect of the present invention. In the laminate 10, a biaxially stretched polyethylene terephthalate film (base film 1) was laminated with a biaxially stretched nylon film 41 (functional film) using the adhesive 2. Further, the heat-sealable film 3 used in FIG. 1 and the biaxially stretched nylon film 41 are laminated by an adhesive 2 to form a laminated film.

FIG. 3 is a sectional view showing an example of a laminated body for food packaging according to still another aspect of the present invention. In the laminate 10, the aluminum foil 42 (functional film) was laminated on the biaxially stretched polyethylene terephthalate film (base film 1) using the adhesive 2. Further, the heat-sealing film 3 used in FIG. 1 and the aluminum foil 42 are laminated by an adhesive 2 to form a laminated film.

FIG. 4 is a sectional view showing an example of a laminate for food packaging according to still another aspect of the present invention. In the laminate 10, a biaxially stretched polyethylene terephthalate film (base film 1), a biaxially stretched nylon film 41, and a functional film 4 made of an aluminum foil 42 were sequentially laminated with an adhesive 2 interposed therebetween. Further, the heat-sealable film 3 and the functional film 4 used in FIG.
It is composed of a laminated film laminated via the.

In the present invention, as the base film 1 constituting the laminated body for food packaging according to the present invention, the heat resistance against heat at the time of heat-sealing, and the physical impact from the outside after packaging are used for packaging. It is preferable to use a film having both impact resistance required to protect the film and contents, and in some cases, barrier properties. Specifically, as the material of the base film 1, a polyethylene terephthalate film (hereinafter referred to as "PET film"), a polyester film such as polybutylene terephthalate film, a polypropylene film (hereinafter referred to as "PP film"), 6 A polyamide film such as a nylon film or a 6,6 nylon film can be preferably used. Generally, by performing biaxial stretching,
A material having further improved heat resistance and impact resistance is used. The thickness of the base film 1 is not particularly limited, but is 5
Those having a thickness of up to 20 μm are usually used. In addition, a metal or a metal oxide may be vapor-deposited and used on the base material film 1 as needed. Base film as needed 1
You may print on the front surface and / or the back surface of this.

As the heat-sealable film 3 constituting the laminate for food packaging according to the present invention, an unstretched polypropylene film (hereinafter referred to as "CCP") which is a propylene-ethylene block copolymer is preferably used. it can. As the CCP, a propylene-ethylene block copolymer (1) (hereinafter, also referred to as “BPP (1)”) as a first component is produced by the method for producing a propylene-ethylene block copolymer described below, and the CCP is produced. An ethylene-butene-1 copolymer containing butene-1 as the two components is hereinafter also referred to as "EBM (1)". ) And / or LLDPE added, it is necessary to use a film formed from a resin composition.

In a preferred embodiment of the present invention, the heat-sealable film 3 is required to have a 32-layer constitution of a layer 31 on the laminate side and a layer in contact with food, and the total layer thickness is 5
The layer thickness ratio of the layer 31 on the laminate side and the layer 32 in contact with the food is preferably 9: 1 to 3: 7.
And preferably 9: 1 to 6: 4. If the ratio of the layer 32 in contact with the food is less than 1, the heat seal strength before and after filling the content is insufficient, and if it exceeds 7, the easy tearing property is insufficient, and
Since the obtained laminate has poor flexibility, impact resistance is reduced.

If necessary, other functional films 4 can be laminated in the laminated product for food packaging according to the present invention. As the film, for example, either one or both of an oxygen barrier layer and a shock absorbing resin layer can be provided. Also, several layers of these layers can be provided. As the oxygen barrier layer, an aluminum foil having a thickness of 5 to 9 μm is generally used, but a film coated with a thin film of vinylidene chloride resin or a film deposited with an inorganic substance such as aluminum, alumina oxide, or silicon oxide is used. You can also A nylon film is preferably used as the shock absorbing resin layer. The nylon film may be uniaxially stretched, biaxially stretched or unstretched, and can be suitably used. The thickness of the shock absorbing resin layer is not particularly limited, but is usually 5 to 40 μm,
It is preferably in the range of 10 to 30 μm.

Next, a method for producing a propylene-ethylene block copolymer will be described.

Propylene and ethylene are used as raw materials for producing a propylene-ethylene block copolymer, but other olefins such as butene-1 may be used, if necessary, so long as the object of the present invention is not impaired. , 4-methyl-pentene-1 and the like can be added.

The catalyst used in the polymerization step is
It is possible to use a magnesium-prone solid catalyst containing magnesium, halogen, titanium, and an electron donor as essential components, a catalyst composed of a solid catalyst component containing titanium trichloride as a main component and organic aluminum, or a metallocene catalyst.

The polymerization step for producing the propylene-ethylene block copolymer is the first step of forming a propylene block consisting of a propylene homopolymer or a propylene-ethylene copolymer having an ethylene content of 2% by weight or less. It comprises a polymerization step and a second polymerization step in which an ethylene-propylene copolymer block having an ethylene content in the range of 20 to 95% by weight is polymerized.

In the first polymerization step, the above-mentioned catalyst is added to the raw material propylene or a mixture of propylene and ethylene to obtain a propylene homopolymer or an ethylene content of 2%.
A propylene block composed of propylene-ethylene copolymer in an amount of not more than 5% by weight is used, and a propylene block of 6% of the total polymer amount finally obtained is used.
It is a step of forming so as to have an amount corresponding to 5 to 95% by weight.

The second polymerization step is carried out subsequent to the first polymerization step, and the mixture of propylene and ethylene is further introduced into the propylene block produced in the first polymerization step so that the ethylene content is 20 to 95% by weight. % Ethylene-propylene block copolymer, 5 to 35 wt% of total polymer amount
Is a step of forming so as to have an amount corresponding to.

The propylene-ethylene block copolymer can be produced by either a batch method or a continuous method. At this time, a method of polymerizing in an inert hydrocarbon solvent such as hexane or heptane, a method of using propylene as a solvent without using a substantially inert solvent, or a method of using a gas on a gas without using a substantially liquid solvent. It is possible to adopt a method of polymerizing in a monomer, or a method of combining these. The first polymerization step and the second polymerization step may use the same polymerization tank or different polymerization tanks.

In order to obtain the heat-sealable film 3 having easy tearability of the present invention, it comprises propylene-ethylene block copolymer and ethylene-butene-1 and / or LLDPE and has a melt flow rate within the above range. The two types of resins to be used may be manufactured by, for example, a film molding method by coextrusion or a film lamination molding method. Specific examples of the film forming method by coextrusion include a coextrusion T-die method, a coextrusion inflation method, and a coextrusion lamination method. The film lamination forming method is more specifically a dry lamination method. Is mentioned.

Of these molding methods, the film molding method by coextrusion is preferable. Unlike the film lamination method, this coextrusion molding method does not require drying of the solvent in the adhesive used during processing, does not require a solvent drying step, and is superior in productivity to film lamination.

To the resin forming each layer of the laminated bag for food packaging, known additives such as a lubricant, an antioxidant, an antistatic agent, and a coloring agent are optionally added within a range not hindering the achievement of the object of the present invention. It can be added. Urethane-based adhesives are preferably used as the adhesive for bonding the films, but other adhesives can be used as long as they are publicly known and do not impair sanitary conditions.

The laminated body for food packaging of the present invention can be manufactured by stacking the laminated bodies 10 described above so that the heat-sealable films face each other and heat-sealing the desired peripheral portion. The method of heat sealing can be a conventionally known method, for example, a heating bar,
External heating methods such as heating knives, heating wires, impulse sealing or internal heating methods such as ultrasonic sealing, dielectric heating sealing can be used.

[0026]

EXAMPLES The present invention will be described below with reference to examples.

(Production Example of BPP (1)) First, BPP (1) as the first component is produced. After fully replacing the stirring autoclave with an internal volume of 200 liters with propylene, 63 liters of sufficiently dehydrated and deoxygenated n-heptane were introduced, and 27 g of diethylaluminum chloride was added.
And titanium trichloride catalyst (made by Marubeni Solvay) 9.0 g
Was introduced under a propylene atmosphere.

In the first polymerization step, the autoclave was heated to 65
After the temperature was raised to 0 ° C., propylene was introduced at a flow rate of 9.0 kg / hour while maintaining the hydrogen concentration at 1.8 vol% to start the process. After 240 minutes, the introduction of propylene was stopped, the polymerization was continued for 90 minutes, and then the gas phase portion was changed to 0.6.
Purging was performed until the pressure became kg / cm ² G to obtain a propylene block (I) made of a propylene homopolymer.

In the second polymerization step, the autoclave is operated at 60
After the temperature was lowered to ℃, propylene was introduced at a flow rate of 2.0 kg / hour and ethylene was introduced at a flow rate of 2.0 kg / hour for 60 minutes to carry out copolymerization to prepare a slurry of the propylene-ethylene block copolymer (1). Obtained.

The slurry thus obtained was filtered and dried to obtain 35.9 kg of BPP (1) powder. Obtained BPP (1) at 230 ° C., 2.16
The MFR (1) under a load of 2.1 kg was 2.1 g / 10 minutes, and the MFR (I) of the propylene block (I) obtained by the first polymerization step and comprising propylene homopolymerization was 3.
It was 4 g / 10 minutes. Further, the ethylene-propylene copolymer block (II) introduced into BPP (1) in the second polymerization step was 10% by weight of the total polymer.

(Production Example of BPP (2)) Next, BP
Produce P (2). After fully replacing the stirring autoclave having an internal capacity of 200 liters with propylene, 63 liters of sufficiently dehydrated and deoxygenated n-heptane were introduced, and 27 g of diethyl aluminum chloride and 9.0 g of titanium trichloride catalyst (manufactured by Marubeni Solvay). Was introduced under a propylene atmosphere.

In the first polymerization step, the autoclave 65
After the temperature was raised to 0 ° C., propylene was introduced at a flow rate of 9.0 kg / hour while maintaining the hydrogen concentration at 3.5 vol% to start the process. After 180 minutes, the introduction of propylene was stopped, the polymerization was continued for 90 minutes, and then the gas phase portion was reduced to 0.2
Purging was performed until the pressure became kg / cm ² G to obtain a propylene block (I) made of a propylene homopolymer.

In the second polymerization step, the autoclave is operated at 60
After cooling to ℃, propylene was introduced at a flow rate of 1.5 kg / hour and ethylene was introduced at a flow rate of 1.5 kg / hour for 180 minutes to carry out copolymerization to prepare a slurry of the propylene-ethylene block copolymer (2). Obtained.

The slurry thus obtained was filtered and dried to obtain 31.6 kg of BPP (2) powder (hereinafter referred to as "BPP (2)"). MFR of the obtained BPP (2) at 230 ° C and a load of 2.16 kg
(1) was 0.8 g / 10 minutes, and the MFR (I) of the propylene block (I) obtained by the propylene homopolymerization obtained in the first polymerization step was 8.4 g / 10 minutes. In addition, the ethylene-propylene copolymer block (I) introduced into BPP (2) in the second polymerization step.
I) was 25% by weight of the total polymer.

(Production Example of BPP (3)) Next, B
PP (3) is produced. After fully replacing the stirring autoclave having an internal capacity of 200 liters with propylene, 63 liters of sufficiently dehydrated and deoxygenated n-heptane were introduced, and 27 g of diethyl aluminum chloride and 9.0 g of titanium trichloride catalyst (manufactured by Marubeni Solvay). Was introduced under a propylene atmosphere.

In the first polymerization step, the autoclave was heated to 65
After the temperature was raised to 0 ° C., propylene was introduced at a flow rate of 9.0 kg / hour while maintaining the hydrogen concentration at 1.8 vol% to start the process. After 240 minutes, the introduction of propylene was stopped, the polymerization was continued for 90 minutes, and then the gas phase portion was changed to 0.6.
Purging was performed until the pressure became kg / cm2G to obtain a propylene block (I) made of a propylene homopolymer.

In the second polymerization step, the autoclave was set at 60.
After the temperature was lowered to ℃, propylene was introduced at a flow rate of 1.5 kg / hour and ethylene was introduced at a flow rate of 1.5 kg / hour for 20 minutes to carry out copolymerization to prepare a slurry of the propylene-ethylene block copolymer (3). Obtained.

The slurry thus obtained was filtered and dried to obtain 29.0 kg of BPP (3) powder (hereinafter referred to as "BPP (3)"). MFR of the obtained BPP (3) at 230 ° C and a load of 2.16 kg
(1) was 3.0 g / 10 minutes, and the MFR (I) of the propylene block (I) obtained by the propylene homopolymerization obtained in the first polymerization step was 3.4 g / 10 minutes. . Also, the ethylene-propylene copolymer block (I) introduced into BPP (3) in the second polymerization step.
I) was 3% by weight of the total polymer.

The types of resins used in the examples of the present invention having the physical properties shown in Table 1 are shown below. Ethylene-butene-1 copolymer (hereinafter referred to as "EBM"): Trade name "Toughmer A-4085" (manufactured by Mitsui Chemicals, Inc.) LLDPE: Trade name "Kernel KC580S" (manufactured by Nippon Polychem Co., Ltd.)

All MFRs in the table are 230 ° C. and 2.16.
It is a value measured with a kg load, and the unit is g / 10 minutes.

[0041]

[Table 1]

(Examples 1 to 3 and Comparative Examples 1 to 4) The resin of the layer (A) on the laminating side shown in Table 2 was used at a temperature of 250 ° C. in the T die section using an extruder (bore diameters of 150 φ and 75 φ). The resin of the layer (B) in contact with food was 75φ and 75φ was melt-coextruded from the T-die so that the layer thickness ratio shown in Table 2 was obtained to obtain a heat-sealing film 3, CPP having a thickness of 70 μm.

[0043]

[Table 2]

Dry lamination using a two-component curing type urethane adhesive layer 2 in the order of a 12 μm thick biaxially stretched PET film (base film 1) and a 7 μm thick aluminum foil (functional film 4). did. Further, a CPP film (heat-sealable film 3) having a thickness of 70 μm was laminated by dry lamination to obtain a laminate 10 composed of PET film / adhesive layer / aluminum foil / adhesive layer / heat-sealable film.

The types of resins used in the examples of the present invention are shown below. Aluminum foil: Product name “JIS IN30” (manufactured by Japan Foil Co., Ltd.) PET film: Product name “Lumilar P60” (manufactured by Toray Co., Ltd.) Urethane adhesive: Product name “A515 / A50” (Mitsui Takeda Chemical ( Co., Ltd.)

(Experiment 1: Tearability test) Examples 1 to 3
And the laminated body 10 obtained in Comparative Examples 1 to 4
Cut two pieces into a size of mx 170 mm, arrange CPP so as to face each other, and perform thermocompression bonding (condition 250 ° C, 2 kg / cm ² , 0.5 second) with a width of 2 mm and a width of 10 mm. ,
A laminated bag for food packaging was obtained. Next, 150 ml of tap water was filled, a notch was made in the seal portion so that the cut direction was the MD direction, and retort sterilization was carried out at 120 ° C. for 30 minutes. Here, the MD direction is the film feeding direction when a resin composition containing a propylene-ethylene block copolymer as a main component is extruded and molded. A notch is a cut end.

After carrying out retort sterilization, both ends of the notch were held by both hands, and tearing was performed while pulling back and forth to evaluate the linear tearability at the time of tearing in two grades: good and poor.

Good: There is no resistance in the MD direction, and tears can be made linearly. It does not tear in the direction perpendicular to the MD direction. Poor: Strong resistance and no straight tearing.

(Experiment 2: Heat Seal Strength Test) The laminates obtained in Examples 1 to 3 and Comparative Examples 1 to
Cut two pieces into a size of 170 mm × 170 mm, arrange CPP so as to face each other, and perform thermocompression bonding (condition 250 ° C., 2 kg / cm ² , 0.5 seconds) with a width of 2 mm and a width of 10 mm. A laminated bag for food packaging was obtained. Next, 150 ml of tap water
Was charged and retort sterilization was performed at 120 ° C. for 30 minutes.

After carrying out the retort sterilization, the heat seal strengths in the MD and TD directions were measured. Here, the TD direction is a direction perpendicular to the MD direction. MD
The heat seal strength in the direction was measured by cutting out a test piece including a heat seal part on the vertical side of the laminated bag for food packaging with a width of 15 mm,
It is measured by pulling this parallel to the MD direction. The heat-sealing strength in the TD direction is measured by cutting out a test piece including a heat-sealing portion on the lateral side with a width of 15 mm and pulling the test piece in parallel with the TD direction.
Therefore, a seal portion having a length of 10 mm and a width of 15 mm is
The seal strength when pulled along the length direction is measured.

The heat seal strength was measured by using a tensile tester (manufactured by Orientec Co., Ltd.) at a tensile speed of 300 mm / min. The results are shown in Table 3. In addition, in Table 3, 15
Heat seal strength per mm (Unit: g / 15mm)
Was described.

(Experiment 3: Dropping bag test) The laminated bodies obtained in Examples 1 to 3 and Comparative Examples 1 to 4 were used to measure 130 mm × 170 mm.
Cut two pieces into a size of mm and arrange the CPPs so that they face each other, and thermocompression-bond them with a width of 2 mm and a width of 10 mm (width: 250 ° C, 2 kg / cm ² , 0.5 seconds) and food. A packaging-like laminated bag was obtained. Then, fill with 150 ml of tap water, 1
Retort sterilization was performed at 20 ° C for 30 minutes.

After carrying out retort sterilization, it was refrigerated at 3 ° C. for one week. Place the sample after refrigeration on the concrete floor with the surface of 130 mm facing down.
After 10 consecutive vertical drops from the height of m, the presence or absence of bag breakage was confirmed. The results are shown in Table 3. In Table 3, the number of broken bags / n (n: the number of bags used in the drop bag test) is shown.

[0054]

[Table 3]

As is clear from the results of Experiments 1 to 3 shown in Table 3, the bag obtained from the laminate for food packaging of the present invention has good tearability, heat sealability, and cold impact resistance. It is a great contribution to the industry.

[0056]

As described above, according to the laminated body for food packaging of the present invention, the heat-sealable film consisting of two layers having the above-mentioned specific resin composition is used, and at the time of film formation. Since it has a layer on the laminate side that is resin-arranged in the MD direction, it has very good linear tearability in the MD direction, and since it has a layer that comes into contact with food, it also has excellent heat seal strength. Further, by using the heat-sealable film of the present invention laminated on a base material film, it is possible to provide a laminate having very good tearability, suitability for heat-sealing, and excellent cold shock resistance. . Moreover, the food packaging laminate of the present invention can be produced relatively easily and inexpensively. By using the bag obtained from the food packaging laminate of the present invention, it is possible to provide a retort food packaging laminate having a very good linear cut property without any problem in storage and distribution in cold regions. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a laminated body for food packaging of the present invention.

FIG. 2 is a cross-sectional view showing an example of a laminated body for food packaging according to another aspect of the present invention.

FIG. 3 is a sectional view showing an example of a laminated body for food packaging according to still another aspect of the present invention.

FIG. 4 is a cross-sectional view showing an example of a food packaging laminate according to still another aspect of the present invention.

[Explanation of symbols] 1 Base film 2 Adhesive layer 3 Heat-sealable film 31 Layer on the laminating side 32 Layers in contact with food 4 Functional film 41 Biaxially stretched nylon film 42 aluminum foil 10 Food packaging laminate

Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08L 53/00 C08L 53/00 // (C08L 53/00 23:08 23:08) C08L 23:06 (C08L 53 / 00 23:06) F-term (reference) 3E064 BA22 BB03 BC15 BC18 3E086 AA23 AC07 AD01 BA04 BA13 BA15 BA33 BB05 BB41 BB51 BB90 CA01 4F100 AK63A AK63B AK64A AK64B AK65A AK65B AL02A AL02B AL05A AL05B BA02 GB23 JA06A JA06B JK03 JL05 JL12 YY00A YY00B 4J002 BB032 BB05X BB052 BP02W BP02Y BP021 GF00 GG02

Claims (3)

[Claims] 1. A laminate comprising a heat-sealable film made of a resin composition containing at least a propylene-ethylene block copolymer resin as a main component and a base film,
In the laminated bag for food packaging formed in a bag shape so that the heat-sealable film is on the inside, the resin composition containing the propylene-ethylene block copolymer resin as a main component is a layer (A) on the laminate side. ) And a layer (B) in contact with food, the layer (A) on the laminate side is a propylene-ethylene block copolymer (1) as the first component.
70 to 90% by weight and 1 of butene-1 as the second component
An ethylene-butene-1 copolymer and / or a low-density linear polyethylene containing 5% by weight or more (hereinafter "LLD"
PE ”. 10 to 30% by weight as a component, and the propylene-ethylene block copolymer (1) as the first component is a propylene homopolymer or a propylene-ethylene copolymer having an ethylene content of 2% by weight or less. A propylene block (I) of 85 to 95% by weight and an ethylene-propylene copolymer block (II) of 5 to 15% by weight having an ethylene content of 20 to 95% by weight, and a melt flow rate (230 ° C., load of 2. 16 kg) is 1.
0 to 4.0 g / 10 minutes, the layer in contact with food (B)
Is ethylene containing 90 to 100% by weight of the propylene-ethylene block copolymer (1) as the first component and 15% by weight or more of butene-1 as the second component.
A laminate for food packaging, which comprises butene-1 copolymer and / or 0 to 10% by weight of LLDPE as a component. 2. The layer according to claim 1, wherein the food-contacting layer (B) comprises 25 to 70% by weight of the propylene-ethylene block copolymer (1) as the first component, and
5 to 30% by weight of an ethylene-butene-1 copolymer containing 15% by weight or more of butene-1 as a component, and a propylene-ethylene block copolymer (2) 2 as a third component
5 to 50% by weight as a component, and the propylene-ethylene block copolymer (2) as the third component is a propylene block composed of a propylene homopolymer or a propylene-ethylene copolymer having an ethylene content of 2% by weight or less. (I) 65 to 85% by weight and ethylene content of 20 to 95
Wt% ethylene-propylene copolymer block (I
I) 15 to 35% by weight, and the melt flow rate (230 ° C., load 2.16 kg) is 0.5 to 1.5 g /
It is 10 minutes, The laminated body for food packaging of Claim 1 characterized by the above-mentioned. 3. The heat-sealable film made of the resin composition containing the propylene-ethylene block copolymer resin as a main component has a total layer thickness of 50 to 100 μm,
3. The food packaging according to claim 1 or 2, characterized in that the layer thickness ratio of the layer (A) on the laminate side and the layer (B) in contact with food is 9: 1 to 3: 7. Laminate.