JP2021066107A - Resin film, laminate and bag - Google Patents

Abstract

To provide a resin film, a laminate and a bag which have environmental load reducing properties, sealability and film formability and are excellent in tearability.SOLUTION: The resin film of the present invention includes at least two layers, i.e., a first layer and a second layer. The first layer and the second layer are laminated directly or via a thermoplastic resin layer. The first layer constitutes the innermost layer of the resin film. The resin film contains polypropylene and polyethylene. A resin composition constituting the first layer contains polypropylene as a main component. The content of polyethylene in the first layer is 20 mass% or less. A resin composition constituting the second layer contains polypropylene as a main component and biomass polyethylene. The content of polyethylene in the second layer is 35 mass% or less.SELECTED DRAWING: Figure 1

Description

The present invention relates to resin films, laminates and bags.

A film made of polypropylene has appropriate flexibility, is excellent in transparency, oil resistance, moisture resistance, chemical resistance, etc., and is inexpensive, so that it is used in various packaging bags and the like. Further, since polypropylene film has a sealing property, it is used for a sealant film such as a packaging bag. For example, Patent Document 1 proposes a multilayer film containing a polypropylene resin layer, and discloses that this multilayer film is used as a sealant film.

However, although polypropylene film is superior to polyethylene film in heat resistance, it has a drawback in that it is inferior to polyethylene film in tearability. Therefore, when the polypropylene film is used for the packaging bag, there is a problem that it becomes difficult to tear and open the packaging bag.

By the way, in recent years, from the viewpoint of suppressing global warming, reduction of carbon dioxide emissions has been required on a global scale, and in the material field as well, it is desired to escape from fossil fuels as well as energy, and biomass The use is attracting attention. Biomass is an organic compound photosynthesized from carbon dioxide and water, and by utilizing it, it becomes carbon dioxide and water again, so-called carbon-neutral renewable energy. In recent years, the practical use of biomass plastics made from these biomass raw materials is rapidly progressing, and attempts are being made to produce various resins from the biomass raw materials.

As for polypropylene, biomass polypropylene made from biomass is on the market. However, the cost of biomass polypropylene is much higher than that of fossil fuel polypropylene, and its practicality is significantly lower.

Japanese Unexamined Patent Publication No. 2005-335108

The present inventors have considered to reduce the amount of fossil fuel polypropylene used and reduce the environmental load by substituting a part of fossil fuel polypropylene with relatively inexpensive biomass polyethylene. However, the resin film containing polypropylene as a main component has a new problem that the sealing property and the film forming property are deteriorated when the proportion of polyethylene is increased. As a result of diligent studies, the present inventors have found that these problems can be solved by forming the resin film into a multilayer structure and adjusting the polyethylene content of each layer. Further, it was found that the tearability of such a resin film having a multi-layer structure is unexpectedly improved.

The present invention has been made in view of the above findings, and an object of the present invention is to provide a resin film, a laminate, and a bag, which have an environmental load reducing property, a sealing property, a film forming property, and particularly an excellent tearing property. To provide.

The present invention is a resin film including at least two layers, a first layer and a second layer, and the first layer and the second layer are laminated either directly or via a thermoplastic resin layer. The first layer constitutes the innermost layer of the resin film, the resin film contains polypropylene and polyethylene, and the resin composition constituting the first layer contains polypropylene as a main component, and the first layer is contained. The polyethylene content of the layer is 20% by mass or less, and the resin composition constituting the second layer contains polypropylene as a main component and biomass polyethylene, and the polyethylene content of the second layer is 35% by mass. % Or less, resin film.

In the resin film according to the present invention, the resin film further includes a third layer, and the third layer is laminated on the second layer directly or via a thermoplastic resin layer, and the resin composition constituting the third layer. The product may contain polypropylene as a main component, and the content of polyethylene in the third layer may be 35% by mass or less.

In the resin film according to the present invention, the biomass degree may be 5% or more.

In the resin film according to the present invention, the biomass degree of the layer constituting the outermost layer of the resin film may be 30% or less.

In the resin film according to the present invention, the polypropylene content may be 66% by mass or more.

In the resin film according to the present invention, the elongation at break in one direction and the other direction orthogonal to the one direction may be 500% or more, respectively.

The present invention is a laminate comprising at least one biaxially stretched plastic film and a resin film according to the present invention.

The present invention is a bag containing the laminate according to the present invention.

According to the present invention, it is possible to provide a resin film, a laminate and a bag having an environmental load reducing property, a sealing property and a film forming property, and particularly excellent in tearability.

FIG. 1 is a cross-sectional view showing an example of the resin film of the present invention. FIG. 2 is a cross-sectional view showing another example of the resin film of the present invention. FIG. 3 is a cross-sectional view showing another example of the resin film of the present invention. FIG. 4 is a cross-sectional view showing another example of the resin film of the present invention. FIG. 5 is a cross-sectional view showing another example of the resin film of the present invention. FIG. 6 is a cross-sectional view showing another example of the resin film of the present invention. FIG. 7 is a cross-sectional view showing an example of the laminated body of the present invention. FIG. 8 is a cross-sectional view showing another example of the laminated body of the present invention. FIG. 9 is a cross-sectional view showing another example of the laminated body of the present invention. FIG. 10 is a cross-sectional view showing another example of the laminated body of the present invention. FIG. 11 is a cross-sectional view showing another example of the laminated body of the present invention. FIG. 12 is a front view showing the bag of the present invention. FIG. 13 is a diagram when a test piece for measuring the sealing strength and low temperature sealing property of the bag of the present invention is cut out. FIG. 14 is a diagram showing how the seal strength and the low temperature seal property are measured using the test piece.

An embodiment of the present invention will be described with reference to FIGS. 1 to 14. In the drawings attached to the present specification, the scale, aspect ratio, etc. are appropriately changed from those of the actual product and exaggerated for the convenience of illustration and comprehension.

In addition, as used in the present specification, the terms such as "parallel", "orthogonal", and "same" and the values of length and angle that specify the shape and geometric conditions and their degrees are strictly used. Without being bound by meaning, we will interpret it including the range in which similar functions can be expected.

Resin film The resin film of the present invention includes two layers, a first layer and a second layer, and the first layer and the second layer are laminated either directly or via a thermoplastic resin layer, and the first layer is a resin. It constitutes the innermost layer of the film. This makes it possible to obtain a resin film having a sealing property. In the resin film of the present invention, the innermost layer is a layer located on the content side to be accommodated when the resin film is used for a bag. Further, the second layer may form the outermost layer of the resin film. In the resin film of the present invention, the outermost layer is a layer located on the opposite side of the innermost layer.
The resin film of the present invention further comprises a third layer, the third of which may be laminated directly or via a thermoplastic resin layer on the second layer. This makes it possible to prevent the occurrence of curl in the resin film. Further, the third layer may form the outermost layer of the resin film.
Hereinafter, an example of the layer structure of the resin film of the present invention will be described with reference to FIGS. 1 to 6.

FIG. 1 is a cross-sectional view showing an example of the resin film 10 of the present invention. The resin film 10 includes a first layer 11 and a second layer 12. The first layer 11 constitutes the innermost layer of the resin film 10. The second layer 12 constitutes the outermost layer of the resin film 10. The first layer 11 and the second layer 12 are directly laminated.

FIG. 2 is a cross-sectional view showing another example of the resin film 10 of the present invention. The resin film 10 includes a first layer 11, a first thermoplastic resin layer 13, and a second layer 12 in this order. The first layer 11 constitutes the innermost layer of the resin film 10. The second layer 12 constitutes the outermost layer of the resin film 10. The first layer 11 and the second layer 12 are laminated via the first thermoplastic resin layer 13.

FIG. 3 is a cross-sectional view showing another example of the resin film 10 of the present invention. The resin film 10 includes a first layer 11, a second layer 12, and a third layer 14 in this order. The first layer 11 constitutes the innermost layer of the resin film 10. The third layer 14 constitutes the outermost layer of the resin film 10. The first layer 11 and the second layer 12 are directly laminated. The second layer 12 and the third layer 14 are directly laminated.

FIG. 4 is a cross-sectional view showing another example of the resin film 10 of the present invention. The resin film 10 includes a first layer 11, a second layer 12, a first thermoplastic resin layer 13, and a third layer 14 in this order. The first layer 11 constitutes the innermost layer of the resin film 10. The third layer 14 constitutes the outermost layer of the resin film 10. The first layer 11 and the second layer 12 are directly laminated. The second layer 12 and the third layer 14 are laminated via the first thermoplastic resin layer 13.

FIG. 5 is a cross-sectional view showing another example of the resin film 10 of the present invention. The resin film 10 includes a first layer 11, a first thermoplastic resin layer 13, a second layer 12, and a third layer 14 in this order. The first layer 11 constitutes the innermost layer of the resin film 10. The third layer 14 constitutes the outermost layer of the resin film 10. The first layer 11 and the second layer 12 are laminated via the first thermoplastic resin layer 13. The second layer 12 and the third layer 14 are directly laminated.

FIG. 6 is a cross-sectional view showing another example of the resin film 10 of the present invention. The resin film 10 includes a first layer 11, a first thermoplastic resin layer 13, a second layer 12, a second thermoplastic resin layer 15, and a third layer 14 in this order. The first layer 11 constitutes the innermost layer of the resin film 10. The third layer 14 constitutes the outermost layer of the resin film 10. The first layer 11 and the second layer 12 are laminated via the first thermoplastic resin layer 13. The second layer 12 and the third layer 14 are laminated via the second thermoplastic resin layer 15.

It is also possible to appropriately combine the plurality of layer configurations of the resin film 10 shown in FIGS. 1 to 6 described above.

The resin film of the present invention contains polypropylene. Examples of polypropylene include propylene-ethylene block copolymers, propylene-ethylene random copolymers, homopolypropylenes, and mixtures of two or more of these.

Here, "propylene-ethylene block copolymer" means a material having a structural formula represented by the following formula (I). In formula (I), m1, m2, and m3 represent integers of 1 or more.

Further, "propylene-ethylene random copolymer" means a material having a structural formula represented by the following formula (II). In formula (II), m and n represent integers of 1 or more.

Further, "homopolypropylene" means a material having a structural formula represented by the following formula (III). In formula (III), m represents an integer of 1 or more.

In the resin film of the present invention, the polypropylene content is preferably 66% by mass or more, more preferably 71% by mass or more and 99% by mass or less, and preferably 74% by mass or more and 95% by mass or less. More preferred. Thereby, the heat resistance and the oil resistance of the resin film can be improved.

In the present specification, unless otherwise specified, "propylene" is obtained from a raw material derived from fossil fuel.

The resin film of the present invention contains polyethylene. Thereby, the tearability of the resin film can be improved. Examples of polyethylene include high-density polyethylene (HDPE), medium-density polyethylene (MDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and a mixture of two or more of these. The resin film of the present invention preferably contains low-density polyethylene, linear low-density polyethylene, and a mixture thereof from the viewpoint of sealing property, and may contain low-density polyethylene from the viewpoint of sealing property and tearability. More preferred.

Here, high density polyethylene refers to polyethylene having a density of greater than 942kg / ^{m 3,} medium density polyethylene refers to polyethylene having a density below 925 kg / ^{m 3} Super 942kg / ^{m 3.}
Further, the low-density polyethylene can also be referred to as a high-pressure method low-density polyethylene, which is a high-pressure method ethylene homopolymer, can be obtained by a conventionally known high-pressure radical polymerization method, and has a density of ^{925 kg / m 3 or less.} Is.
Further, the linear low-density polyethylene is a copolymer of ethylene and α-olefin polymerized using a multisite catalyst represented by a Ziegler-Natta catalyst or a single site catalyst represented by a metallocene catalyst. , Polyethylene having a density of 925 kg / m ³ or less.

In the resin film of the present invention, the content of polyethylene is preferably 29% by mass or less, more preferably 1% by mass or more and 28% by mass or less, and 5% by mass or more and 26% by mass or less. More preferred.

The polyethylene of the resin film may be fossil fuel polyethylene, biomass polyethylene, or a combination thereof. The resin film of the present invention preferably contains biomass polyethylene from the viewpoint of reducing the environmental load. Hereinafter, biomass polyethylene will be described.

<Biomass-derived ethylene>
The method for producing biomass-derived ethylene, which is a raw material for biomass polyethylene, is not particularly limited, and can be obtained by a conventionally known method. Hereinafter, an example of a method for producing ethylene-derived ethylene will be described.

Biomass-derived ethylene can be produced using biomass-derived ethanol as a raw material. In particular, it is preferable to use fermented ethanol derived from biomass obtained from plant raw materials. The plant material is not particularly limited, and conventionally known plants can be used. For example, corn, sugar cane, beets, and manioc can be mentioned.

Biomass-derived fermented ethanol refers to ethanol that has been purified after being produced by contacting a culture solution containing a carbon source obtained from a plant material with a microorganism that produces ethanol or a product derived from a crushed product thereof. Conventionally known methods such as distillation, membrane separation, and extraction can be applied to the purification of ethanol from the culture broth. For example, a method of adding benzene, cyclohexane or the like and azeotropically boiling the mixture, or removing water by membrane separation or the like can be mentioned.

In order to obtain the above ethylene, advanced purification such as reducing the total amount of impurities in ethanol to 1 ppm or less may be further performed at this stage.

A catalyst is usually used when ethylene is obtained by a dehydration reaction of ethanol, but the catalyst is not particularly limited, and a conventionally known catalyst can be used. Advantageous in the process is a fixed bed flow reaction in which the catalyst and the product can be easily separated, and for example, γ-alumina and the like are preferable.

Since this dehydration reaction is an endothermic reaction, it is usually carried out under heating conditions. As long as the reaction proceeds at a commercially useful reaction rate, the heating temperature is not limited, but a temperature of 100 ° C. or higher, more preferably 250 ° C. or higher, still more preferably 300 ° C. or higher is suitable. The upper limit is not particularly limited, but is preferably 500 ° C. or lower, more preferably 400 ° C. or lower, from the viewpoint of energy balance and equipment.

In the dehydration reaction of ethanol, the yield of the reaction depends on the amount of water contained in the ethanol supplied as a raw material. Generally, when a dehydration reaction is carried out, it is preferable that there is no water in consideration of the efficiency of removing water. However, in the case of the dehydration reaction of ethanol using a solid catalyst, it was found that the amount of other olefins, especially butene, tends to increase in the absence of water. It is presumed that it is not possible to suppress ethylene dimerization after dehydration without the presence of a small amount of water. The lower limit of the allowable water content is 0.1% by mass or more, preferably 0.5% by mass or more. The upper limit is not particularly limited, but from the viewpoint of mass balance and heat balance, it is preferably 50% by mass or less, more preferably 30% by mass or less, and further preferably 20% by mass or less.

By performing the ethanol dehydration reaction in this way, a mixed portion of ethylene, water and a small amount of unreacted ethanol can be obtained. However, since ethylene is a gas at about 5 MPa or less at room temperature, it is separated from these mixed portions by gas-liquid separation. Ethylene can be obtained except for water and ethanol. This may be done by a known method.

Ethylene obtained by gas-liquid separation is further distilled, and the distillation method, operating temperature, residence time, and the like are not particularly limited except that the operating pressure at this time is normal pressure or higher.

When the raw material is ethanol derived from ammonia, the obtained ethylene contains carbonyl compounds such as ketones, aldehydes, and esters, which are impurities mixed in the ethanol fermentation process, carbon dioxide gas, which is a decomposition product thereof, and decomposition products of enzymes. It contains a very small amount of nitrogen-containing compounds such as amines and amino acids, which are impurities, and ammonia, which is a decomposition product thereof. Depending on the use of ethylene, these trace amounts of impurities may cause a problem and may be removed by purification. The purification method is not particularly limited, and can be performed by a conventionally known method. As a suitable purification operation, for example, an adsorption purification method can be mentioned. The adsorbent used is not particularly limited, and conventionally known adsorbents can be used. For example, a material having a high surface area is preferable, and the type of adsorbent is selected according to the type and amount of impurities in ethylene obtained by the dehydration reaction of ethanol derived from biomass.

In addition, caustic water treatment may be used in combination as a method for purifying impurities in ethylene. When caustic water treatment is performed, it is desirable to perform it before adsorption purification. In that case, it is necessary to perform a water removal treatment after the caustic treatment and before the adsorption purification.

<Biomass polyethylene>
Biomass polyethylene is obtained by polymerizing a monomer containing ethylene derived from biomass. As the biomass-derived ethylene, it is preferable to use the ethylene obtained by the above-mentioned production method. Since ethylene derived from biomass is used as the monomer as a raw material, the polyethylene polymerized is derived from biomass. Examples of the biomass polyethylene include biomass linear low-density polyethylene manufactured by Braskem (trade name: SLL318, density: 918 kg / m ³ , MFR: 2.7 g / 10 minutes, biomass degree 87%), manufactured by Braskem. Biomass low density polyethylene (trade name: SEB853, density: 923 kg / m ³ , MFR: 2.7 g / 10 minutes, biomass degree 95%) and the like can be used. The raw material monomer for polyethylene does not have to contain 100% by mass of ethylene derived from biomass.

As long as the object of the present invention is not impaired, the monomer which is a raw material of biomass polyethylene may further contain ethylene derived from fossil fuel.

In the present invention, the "biomass degree" is indicated by the weight ratio of the biomass-derived component.

Since carbon dioxide in the atmosphere contains C14 at a fixed ratio (105.5 pMC), the C14 content in plants that grow by taking in carbon dioxide in the atmosphere, for example, corn, is also about 105.5 pMC. It is known. It is also known that fossil fuels contain almost no C14. Therefore, the proportion of biomass-derived carbon can be calculated by measuring the proportion of C14 contained in all carbon atoms. In the present invention, the "biomass degree" indicates the weight ratio of the biomass-derived component. For example, taking polyethylene terephthalate as an example, polyethylene terephthalate is obtained by polymerizing ethylene glycol containing 2 carbon atoms and terephthalic acid containing 8 carbon atoms at a molar ratio of 1: 1 and therefore is derived from biomass as ethylene glycol. When only one is used, the weight ratio of the biomass-derived component in the polyester is 31.25%, so that the theoretical value of the degree of biomass is 31.25%. Specifically, the mass of polyethylene terephthalate is 192, of which the mass derived from biomass-derived ethylene glycol is 60, so 60 ÷ 192 × 100 = 31.25. Further, the weight ratio of the biomass-derived component in the fossil fuel-derived polyester produced by using the fossil fuel-derived ethylene glycol and the fossil fuel-derived dicarboxylic acid is 0%, and the biomass degree of the fossil fuel-derived polyester is It becomes 0%. Hereinafter, unless otherwise specified, the "biomass degree" shall indicate the weight ratio of the biomass-derived components.

In the present invention, theoretically, if all biomass-derived ethylene is used as the raw material for polyethylene, the biomass-derived ethylene concentration is 100%, and the biomass degree of biomass polyethylene is 100%. Further, the biomass-derived ethylene concentration in the fossil fuel polyethylene produced only from the fossil fuel-derived raw material is 0%, and the biomass degree of the fossil fuel polyethylene is 0%.

In the present invention, the biomass polyethylene or the resin layer derived from biomass does not need to have a biomass degree of 100%. This is because if a raw material derived from biomass is used even in a part of the resin film, it is in line with the purpose of reducing the amount of fossil fuel used as compared with the conventional case.

The resin film preferably has a biomass degree of 5% or more. As a result, the environmental load reduction property can be further improved. The biomass degree of the resin film is more preferably 5% or more and 90% or less, further preferably 5% or more and 50% or less, and even more preferably 10 or more and 25% or less.

The thickness of the resin film of the present invention is preferably 15 μm or more and 250 μm or less, more preferably 20 μm or more and 200 μm or less, and further preferably 20 μm or more and 150 μm or less. Thereby, the sealing property of the resin film can be further improved.

In the resin film of the present invention, the thickness of the second layer is preferably equal to or greater than the thickness of the first layer. Thereby, the sealing property and the tearing property of the resin film can be improved. The ratio of the thickness of the first layer: the second layer is preferably 1: 8 to 1: 1 and more preferably 1: 5 to 1: 1.
When the resin film includes the third layer, the thickness of the second layer is preferably equal to or greater than the thickness of the third layer. Thereby, it is possible to improve the interlayer lamination strength and the tearability with the multilayer. The ratio of the thickness of the second layer: the third layer is preferably 8: 1 to 1: 1 and more preferably 5: 1 to 1: 1.

The resin film of the present invention preferably has a breaking elongation of 500% or more in one direction and in the other direction orthogonal to one direction. The elongation at break of the resin film in the present invention shall be performed in accordance with JIS K7127. Using the Tencilon universal material tester RTC-1310A (manufactured by A & D Co., Ltd.), the test piece was held for 1 minute in an environment with a temperature of 25 ° C and a relative humidity of 50%, and then the temperature was 25 ° C and the relative humidity was 50. Measure in% environment. The measurement was performed using a rectangular test piece having a side of 15 mm and a direction orthogonal to the side of 150 mm, and the initial distance between the gripping tools was 100 mm and the tensile speed was 300 mm / min. As long as the distance between the initial grippers can be measured as 100 mm, the length in the direction orthogonal to one side can be adjusted.

The breaking elongation (%) of the resin film in the flow direction (MD) is preferably 500% or higher. The elongation at break of the resin film in the flow direction (MD) is preferably 700% or more, more preferably 800% or more. Further, the breaking elongation of the resin film in the vertical direction (TD) orthogonal to the flow direction is preferably 500% or more. The elongation at break of the resin film in the vertical direction (TD) is preferably 700% or more, more preferably 800% or less, and further preferably 900% or more.

The above-mentioned one direction may be a direction different from the flow direction (MD) or the vertical direction (TD).

Hereinafter, the first layer, the second layer, the third layer, and the thermoplastic resin layer will be described in detail.

(1st layer)
The first layer is composed of a resin composition containing polypropylene as a main component. Thereby, the heat resistance and the oil resistance of the resin film can be improved. In the present specification, "containing as a main component" and "main component" mean that the content exceeds 50% by mass. Examples of polypropylene include propylene-ethylene block copolymers, propylene-ethylene random copolymers, homopolypropylenes, and mixtures of two or more of these. The resin composition constituting the first layer preferably contains a propylene-ethylene block copolymer from the viewpoint of sealing strength, and may contain a propylene-ethylene random copolymer from the viewpoint of low-temperature sealing property. preferable.

In the resin composition constituting the first layer, the polypropylene content is preferably 51% by mass or more, more preferably 70% by mass or more, and further preferably 90% by mass or more. Thereby, the heat resistance and the oil resistance of the resin film can be further improved.

The resin composition constituting the first layer may contain polyethylene. Thereby, the tearability of the resin film can be improved. Examples of polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and a mixture of two or more of these. The resin composition constituting the first layer preferably contains low-density polyethylene, linear low-density polyethylene, and a mixture thereof from the viewpoint of sealing property.

When a mixture of polypropylene and polyethylene is used as the resin composition constituting the first layer, the resin composition constituting the first layer may have a sea-island structure. Here, the "sea island structure" refers to a structure in which polyethylene is discontinuously dispersed in a region in which polypropylene is continuous. By having the sea-island structure, the tearability of the resin film can be further improved.

In the resin composition constituting the first layer, the content of polyethylene is 20% by mass or less. This makes it possible to obtain a resin film having a sealing property. The content of polyethylene in the resin composition constituting the first layer is preferably 15% by mass or less, and more preferably 10% by mass or less.

The polyethylene of the resin composition constituting the first layer may be fossil fuel polyethylene, biomass polyethylene, or a combination thereof. The resin composition constituting the first layer preferably contains biomass polyethylene from the viewpoint of reducing the environmental load.

In the resin composition constituting the first layer, the biomass degree is preferably 50% or less. The resin obtained from the raw material derived from biomass has a higher proportion of low molecular weight components than the resin obtained from the raw material derived from fossil fuel, and this low molecular weight component may affect the sealing property of the resin film. is there. Therefore, by setting the biomass degree of the resin composition constituting the first layer to 50% or less, the influence on the sealing property can be reduced. From the viewpoint of reducing environmental load and sealing property, the biomass degree of the resin composition constituting the first layer is preferably 0.1% or more and 25% or less, and more preferably 1% or more and 15% or less. preferable.

The resin composition constituting the first layer is preferably 1 g / 10 minutes or more and 30 g / 10 minutes or less, more preferably 3 g / 10 minutes or more and 25 g / 10 minutes or less, and further preferably 5 g / 10 minutes or more and 20 g / 10 minutes. It has the following melt flow rate (MFR). The melt flow rate is a value measured by the method A under the conditions of a temperature of 190 ° C. and a load of 21.18 N in the method specified in JIS K7210-2014. When the MFR of the resin composition constituting the first layer is 1 g / 10 minutes or more, the extrusion load during the molding process can be reduced. Further, when the MFR of the resin composition constituting the first layer is 30 g / 10 minutes or less, the mechanical strength of the resin film can be increased.

The thickness of the first layer is preferably 5 μm or more and 100 μm or less, more preferably 5 μm or more and 80 μm or less, and further preferably 10 μm or more and 50 μm or less. Thereby, the sealing property of the resin film can be further improved. Further, the first layer may be composed of two or more layers.

As long as the characteristics of the present invention are not impaired, the resin composition constituting the first layer is an antioxidant, an antiblocking agent, a lubricant, a filler, a plasticizer, an antistatic agent, an ultraviolet absorber, an inorganic particle, and an organic particle. , One or more additives such as mold release agent and dispersant may be contained.

(2nd layer)
The second layer is composed of a resin composition containing polypropylene as a main component and biomass polyethylene. When the resin composition constituting the second layer contains polypropylene as a main component, the heat resistance and oil resistance of the resin film can be improved. Further, when the resin composition constituting the second layer contains biomass polyethylene, it is possible to improve the environmental load reduction property and the tear property of the resin film.

The resin composition constituting the second layer may have a sea-island structure. By having the sea-island structure, the tearability of the resin film can be further improved.

In the resin composition constituting the second layer, examples of polypropylene include propylene-ethylene block copolymer, propylene-ethylene random copolymer, homopolypropylene, and a mixture of two or more thereof. The resin composition constituting the second layer preferably contains a propylene-ethylene block copolymer from the viewpoint of sealing strength, and may contain a propylene-ethylene random copolymer from the viewpoint of low-temperature sealing property. preferable.

In the resin composition constituting the second layer, the polypropylene content is preferably 51% by mass or more, more preferably 60% by mass or more, and further preferably 70% by mass or more. Thereby, the heat resistance and the oil resistance of the resin film can be further improved.

In the resin composition constituting the second layer, the biomass polyethylene includes, for example, biomass high-density polyethylene, biomass medium-density polyethylene, biomass low-density polyethylene, biomass linear low-density polyethylene, and a mixture of two or more of these. Can be mentioned. The resin composition constituting the second layer preferably contains biomass low-density polyethylene from the viewpoint of tearability.

In the resin composition constituting the second layer, the biomass degree is preferably 5% or more. As a result, the environmental load reduction property of the resin film can be further improved. The biomass degree of the resin composition constituting the second layer is more preferably 5% or more and 95% or less, and further preferably 10% or more and 50% or less.

When the second layer constitutes the outermost layer of the resin film, the biomass degree of the resin composition constituting the second layer is preferably 30% or less. The resin obtained from the raw material derived from biomass has a higher proportion of low molecular weight components than the resin obtained from the raw material derived from fossil fuel, and this low molecular weight component may affect the adhesion to other layers. There is sex. By setting the biomass degree of the resin composition constituting the second layer to 30% or less, the influence on the adhesion to other layers can be reduced. From the viewpoint of reducing environmental load and adhesion, the biomass degree of the resin composition constituting the second layer is preferably 1% or more and 27% or less, and more preferably 5% or more and 20% or less.

The resin composition constituting the second layer may contain fossil fuel polyethylene as long as the characteristics of the present invention are not impaired. Examples of fossil fuel polyethylene include fossil fuel high-density polyethylene, fossil fuel medium-density polyethylene, fossil fuel low-density polyethylene, fossil fuel linear low-density polyethylene, and a mixture of two or more of these.

In the resin composition constituting the second layer, the content of polyethylene is 35% by mass or less. This makes it possible to obtain a resin film having film-forming properties. The content of polyethylene in the resin composition constituting the second layer is preferably 5% by mass or more and 30% by mass or less, and preferably 15% by mass or more and 30% by mass or less. Thereby, the tearability of the resin film can be improved.

The resin composition constituting the second layer is preferably 1 g / 10 minutes or more and 30 g / 10 minutes or less, more preferably 3 g / 10 minutes or more and 25 g / 10 minutes or less, and further preferably 5 g / 10 minutes or more and 20 g / 10 minutes. It has the following melt flow rate (MFR). When the MFR of the resin composition constituting the second layer is 1 g / 10 minutes or more, the extrusion load during the molding process can be reduced. Further, when the MFR of the resin composition constituting the second layer is 30 g / 10 minutes or less, the mechanical strength of the resin film can be increased.

The thickness of the second layer is preferably 10 μm or more and 150 μm or less, more preferably 15 μm or more and 120 μm or less, and further preferably 20 μm or more and 100 μm or less. Thereby, the sealing property of the resin film can be further improved. Further, the second layer may be composed of two or more layers.

As long as the characteristics of the present invention are not impaired, the resin composition constituting the second layer is an antioxidant, an antiblocking agent, a lubricant, a filler, a plasticizer, an antistatic agent, an ultraviolet absorber, an inorganic particle, and an organic particle. , One or more additives such as mold release agent and dispersant may be contained.

(Third layer)
The third layer is composed of a resin composition containing polypropylene as a main component. Thereby, the heat resistance and the oil resistance of the resin film can be improved. Examples of polypropylene include propylene-ethylene block copolymers, propylene-ethylene random copolymers, homopolypropylenes, and mixtures of two or more of these. The resin composition constituting the third layer preferably contains a propylene-ethylene block copolymer from the viewpoint of sealing strength, and may contain a propylene-ethylene random copolymer from the viewpoint of low-temperature sealing property. preferable.

In the resin composition constituting the third layer, the polypropylene content is preferably 51% by mass or more, more preferably 70% by mass or more, and further preferably 90% by mass or more. Thereby, the heat resistance and the oil resistance of the resin film can be further improved.

In the resin film of the present invention, the difference between the polypropylene content in the resin film constituting the third layer and the polypropylene content in the resin film constituting the first layer is preferably 30% by mass or less. , 20% by mass or less, more preferably 10% by mass or less. Thereby, the curl of the resin film can be further reduced.

The resin composition constituting the third layer may contain polyethylene. Thereby, the tearability of the resin film can be improved. When the resin composition constituting the first layer contains polyethylene, examples of the polyethylene include high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene, and a mixture of two or more of these. ..

When a mixture of polypropylene and polyethylene is used as the resin composition constituting the third layer, the resin composition constituting the third layer may have a sea-island structure. By having the sea-island structure, the tearability of the resin film can be further improved.

In the resin composition constituting the third layer, the content of polyethylene is 35% by mass or less. This makes it possible to obtain a resin film having film-forming properties. Regarding the content of polyethylene in the resin composition constituting the third layer, the content of polyethylene is preferably 1% by mass or more and 30% by mass or less, and preferably 5% by mass or more and 25% by mass or less. .. Thereby, the tearability of the resin film can be improved.

The polyethylene of the resin composition constituting the third layer may be fossil fuel polyethylene, biomass polyethylene, or a combination thereof. The resin composition constituting the third layer preferably contains biomass polyethylene from the viewpoint of reducing the environmental load.

When the third layer constitutes the outermost layer of the resin film, the biomass degree of the resin composition constituting the third layer is preferably 30% or less. The resin obtained from the raw material derived from biomass has a higher proportion of low molecular weight components than the resin obtained from the raw material derived from fossil fuel, and this low molecular weight component may affect the adhesion to other layers. There is sex. By setting the biomass degree of the resin composition constituting the third layer to 30% or less, the influence on the adhesion to other layers can be reduced. From the viewpoint of reducing environmental load and adhesion, the biomass degree of the resin composition constituting the third layer is preferably 1% or more and 25% or less, and more preferably 5% or more and 20% or less.

The resin composition constituting the third layer is preferably 1 g / 10 minutes or more and 30 g / 10 minutes or less, more preferably 3 g / 10 minutes or more and 25 g / 10 minutes or less, and further preferably 5 g / 10 minutes or more and 20 g / 10 minutes. It has the following melt flow rate (MFR). When the MFR of the resin composition constituting the third layer is 1 g / 10 minutes or more, the extrusion load during the molding process can be reduced. Further, when the MFR of the resin composition constituting the third layer is 30 g / 10 minutes or less, the mechanical strength of the resin film can be increased.

The thickness of the third layer is preferably 5 μm or more and 100 μm or less, more preferably 5 μm or more and 80 μm or less, and further preferably 10 μm or more and 50 μm or less. Thereby, the adhesion with other layers can be further improved. Further, the third layer may be composed of two or more layers.

As long as the characteristics of the present invention are not impaired, the resin composition constituting the third layer is an antioxidant, an antiblocking agent, a lubricant, a filler, a plasticizer, an antistatic agent, an ultraviolet absorber, an inorganic particle, and an organic particle. , One or more additives such as mold release agent and dispersant may be contained.

(Thermoplastic resin layer)
The thermoplastic resin layer is a layer formed for laminating any two layers. The thermoplastic resin layer can be formed by a conventionally known method, for example, a melt extrusion laminating method or a sand laminating method. As the material of the thermoplastic resin layer, a polyolefin resin such as a polyethylene resin or a polypropylene resin, a cyclic polyolefin resin, or a copolymer resin containing these resins as a main component, a modified resin, or a mixture (alloy). Including) can be used. Examples of the polyolefin resin include low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene, ethylene-α-olefin copolymer polymerized using a metallocene catalyst, and random ethylene-polypropylene. Alternatively, block copolymer, ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methacrylate copolymer (EMAA). , Ethylene-methyl methacrylate copolymer (EMMA), ethylene-maleic acid copolymer, ionomer resin, and in order to improve the adhesion between layers, the above-mentioned polyolefin-based resin is used as acrylic acid, methacrylate, malein. An acid-modified polyolefin-based resin modified with an unsaturated carboxylic acid such as an acid, maleic anhydride, fumaric acid, or itaconic acid can be used. Further, as the polyolefin resin, an unsaturated carboxylic acid, an unsaturated carboxylic acid anhydride, a resin obtained by graft-polymerizing or copolymerizing an ester monomer or the like can be used. These materials can be used alone or in combination of two or more. As the cyclic polyolefin resin, for example, cyclic polyolefins such as ethylene-propylene copolymer, polymethylpentene, polybutene, and polynorbonene can be used. These resins can be used alone or in combination of two or more.

The thermoplastic resin layer may contain a resin obtained from a raw material derived from biomass, or may contain a resin obtained from a raw material derived from fossil fuel.

(Manufacturing method of resin film)
The method for producing the resin film of the present invention is not particularly limited, and the resin film can be produced by a conventionally known method. The resin film is preferably coextruded, and more preferably coextruded by the T-die method or the inflation method. Hereinafter, an example of a method for producing a resin film by the T-die method and the inflation method will be described.

In the T-die method, after the raw materials of the resin composition constituting the first layer and the raw materials of the resin composition constituting the second layer are dried, the temperatures (Tm) to Tm + 70 ° C. above the melting point of each of these are obtained. Supply to a melt extruder heated to the above temperature, melt them, co-extrude them into a sheet from a T-die die, and quench and solidify the co-extruded sheet with a rotating cooling drum or the like. Can form a resin film.
As the melt extruder, a single-screw extruder, a twin-screw extruder, a vent extruder, a tandem extruder and the like can be used depending on the purpose.

In the inflation method, first, the raw material of the resin composition constituting the first layer and the raw material of the resin composition constituting the second layer are dried, and then the temperatures (Tm) to Tm + 70 above the melting point of each of these are dried. It is supplied to a melt extruder heated to a temperature of ° C., melted, and co-extruded into a cylindrical shape by a die of an annular die. At this time, air is sent from below into the cylindrical molten resin to expand the diameter of the cylinder to a predetermined size, and cooling air is sent from below to the outside of the cylinder. This expanded cylindrical body is called a bubble. Subsequently, the bubble is folded into a film by a guide plate and a pinch roll, and wound up at the winding portion. The folded film may be wound in a tubular shape, or both ends of the cylinder may be removed with a slitter or the like, separated into two films, and then each may be wound. As a result, the resin film can be molded.
As the melt extruder, a single-screw extruder, a twin-screw extruder, a vent extruder, a tandem extruder and the like can be used depending on the purpose.

Laminated body Next, the laminated body 20 of the present invention will be described. The laminate 20 includes at least one biaxially stretched plastic film and the resin film 10 described above. By including the resin film 10 in the laminate, it is possible to obtain a laminate having an environmental load reduction property, a sealing property, and an excellent tear property.

FIG. 7 is a cross-sectional view showing an example of the laminated body 20 of the present invention. As shown in FIG. 7, the laminate 20 includes a first biaxially stretched plastic film 21, a printing layer 22, a first adhesive layer 23, and the resin film 10 in this order. The first biaxially stretched plastic film 21 constitutes the outer surface 20y of the laminate 20, and the resin film 10 constitutes the inner surface 20x.

FIG. 8 is a cross-sectional view showing an example of the laminated body 20 of the present invention. As shown in FIG. 8, the laminate 20 includes a first biaxially stretched plastic film 21, a printing layer 22, a first adhesive layer 23, a second biaxially stretched plastic film 24, and a second. The adhesive layer 25 and the resin film 10 are included in this order. The first biaxially stretched plastic film 21 constitutes the outer surface 20y of the laminate 20, and the resin film 10 constitutes the inner surface 20x.

FIG. 9 is a cross-sectional view showing another example of the laminated body 20 of the present invention. As shown in FIG. 9, the laminate 20 includes a first biaxially stretched plastic film 21, a printing layer 22, a first adhesive layer 23, a metal leaf 26, and a second adhesive layer 25. , The resin film 10 is included in this order. The first biaxially stretched plastic film 21 constitutes the outer surface 20y of the laminate 20, and the resin film 10 constitutes the inner surface 20x.

FIG. 10 is a cross-sectional view showing another example of the laminated body 20 of the present invention. As shown in FIG. 4, the laminate 20 includes a first biaxially stretched plastic film 21, a printing layer 22, a first adhesive layer 23, a thin-film deposition layer 27, and a second biaxially stretched plastic film. 24, the second adhesive layer 25, and the resin film 10 are included in this order. The first biaxially stretched plastic film 21 constitutes the outer surface 20y of the laminate 20, and the resin film 10 constitutes the inner surface 20x.

FIG. 11 is a cross-sectional view showing another example of the laminated body 20 of the present invention. As shown in FIG. 5, the laminate 20 includes a first biaxially stretched plastic film 21, a printing layer 22, a first anchor coat layer 28, a first adhesive resin layer 29, and a vapor deposition layer 27. , The second biaxially stretched plastic film 24, the second anchor coat layer 30, the second adhesive resin layer 31, and the resin film 10 are included in this order. The first biaxially stretched plastic film 21 constitutes the outer surface 20y of the laminate 20, and the resin film 10 constitutes the inner surface 20x.

Hereinafter, the first biaxially stretched plastic film 21, the second biaxially stretched plastic film 24, the printing layer 22, the metal foil 26, the vapor deposition layer 27, the first adhesive layer 23, the second adhesive layer 25, The first anchor coat layer 28, the second anchor coat layer 30, the first adhesive resin layer 29, and the second adhesive resin layer 31 will be described in detail.

(First biaxially stretched plastic film and second biaxially stretched plastic film)
Examples of the resin material constituting the first biaxially stretched plastic film and the second biaxially stretched plastic film include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), 1,4. -Polycyclohexylene methylene terephthalate, polyester such as terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymer, polyamide such as nylon 6 and nylon 6,6, polyolefin such as polyethylene, polypropylene and polymethylpentene, polyvinyl chloride, Vinyl resins such as polyvinyl alcohol (PVA), polyvinyl acetate, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral and polyvinylpyrrolidone (PVP), (meth) acrylic resins such as polyacrylate, polymethacrylate and polymethylmethacrylate. , Cellophane, cellulose acetate, nitrocellulose, cellulose resins such as cellulose acetate propionate (CAP) and cellulose acetate butyrate (CAB), styrene resins such as polystyrene (PS), and chlorinated resins thereof.
Among these, polyolefins, polyesters and polyamides are preferable, and polypropylene, polyethylene terephthalate, and nylon 6 and nylons 6 and 6 are more preferable. In the present invention, "(meth) acrylic" means "acrylic" and "methacrylic". Means to include both. Further, "(meth) acrylate" means to include both "acrate" and "metaaclate".

To the extent that the characteristics of the present invention are not impaired, the first biaxially stretched plastic film and the second biaxially stretched plastic film are fillers, plasticizers, antistatic agents, ultraviolet absorbers, inorganic particles, organic particles, and release. It may contain additives such as molds and dispersants.

(Print layer)
The printing layer is a layer printed on the first biaxially stretched plastic film in order to show product information or give a aesthetic impression to the bag. The print layer represents characters, numbers, symbols, figures, patterns, and the like. As a material constituting the print layer, an ink for gravure printing or an ink for flexographic printing can be used.

The inks that make up the print layer include binders and pigments. The binder includes, for example, polyurethane and the like as well as the first adhesive layer and the second adhesive layer. Polyurethane is a cured product produced by the reaction of a polyol as a main agent and an isocyanate compound as a curing agent. Details of the polyol and isocyanate compounds will be described in the paragraphs of the first adhesive layer and the second adhesive layer.

The pigment in the printing layer is a colored powder and is present in the binder at a predetermined distribution density. The color exhibited by the pigment is not particularly limited, and various pigments such as red, blue, green, white, and black can be used. For example, the average particle size of the pigment may be 0.1 μm or more and 1 μm or less, or 0.5 μm or more and 1 μm or less. It should be noted that white pigments generally have larger dimensions than pigments of other colors. For example, the average particle size of the white pigment is 0.5 μm or more and 1 μm or less. The average particle size of the pigment can be measured by a dynamic light scattering method.

The print layer may consist of a single layer or may include a plurality of layers. For example, the printing layer may include a first layer containing a pigment exhibiting a first color and a second layer containing a pigment exhibiting a second color different from the first color. The thickness of one layer of the printing layer is, for example, 0.5 μm or more and 3 μm or less.

(Metal leaf)
As the metal foil, a conventionally known metal foil can be used. Aluminum foil is preferable from the viewpoint of gas barrier property that blocks the transmission of oxygen gas, water vapor, and the like, and light-shielding property that blocks the transmission of visible light, ultraviolet rays, and the like. The thickness of the metal foil is, for example, 5 μm or more and 15 μm or less.

(Embedded layer)
The thin-film deposition layer is a layer provided to enhance the gas barrier property of the bag. The vapor deposition layer is, for example, silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B), titanium (Ti). , Lead (Pb), zirconium (Zr), yttrium (Y) and the like, and one or more kinds of inorganic substances or inorganic oxide vapor deposition films are provided. The vapor deposition layer may include one layer or two or more vapor deposition films.

The vapor-deposited film can be formed by depositing the above-mentioned inorganic substance or inorganic oxide on one side of a film such as the above-mentioned biaxially stretched plastic film. Examples of the method for forming the vapor-deposited film include known methods such as a vacuum vapor deposition method, a sputtering method, and a chemical vapor deposition method.

The film thickness of the thin-film film of the inorganic substance or the inorganic oxide is 100 Å to 2000 Å, preferably 200 Å to 1000 Å.

The vapor-deposited layer may be provided with a gas-barrier coating film on the vapor-deposited film of the inorganic substance and the inorganic oxide as described above in order to enhance the gas barrier property. The gas barrier coating film is of the general formula R ¹ _n M (OR ² ) _m (where R ¹ and R ² represent organic groups having 1 to 8 carbon atoms, M represents a metal atom, and n. Represents an integer of 0 or more, m represents an integer of 1 or more, and n + m represents the valence of M). Obtained from a transparent gas barrier composition containing a resin and / or an ethylene / vinyl alcohol copolymer and further polycondensing by the solgel method in the presence of a solgel method catalyst, acid, water and an organic solvent. ..

(First adhesive layer and second adhesive layer)
The adhesive layer such as the first adhesive layer and the second adhesive layer contains an adhesive for adhering the first biaxially stretched plastic film, the second biaxially stretched plastic film, and the like to each other. The adhesive constituting the adhesive layer is produced from an adhesive composition prepared by mixing a first composition containing a main agent and a solvent and a second composition containing a curing agent and a solvent. Specifically, the adhesive contains a cured product produced by the reaction of the main agent and the solvent in the adhesive composition.

Examples of the adhesive include an ether-based two-component reaction type adhesive or an ester-based two-component reaction type adhesive. Examples of the ether-based two-component reaction type adhesive include polyether polyurethane and the like. The polyether polyurethane is a cured product produced by reacting a polyether polyol as a main agent with an isocyanate compound as a curing agent. Examples of the ester-based two-component reaction type adhesive include polyester polyurethane and polyester. Polyester polyurethane is a cured product produced by the reaction of a polyester polyol as a main agent and an isocyanate compound as a curing agent.

Examples of the isocyanate compound that reacts with a polyol such as a polyether polyol or a polyester polyol to form a cured product include an aromatic isocyanate compound and an aliphatic isocyanate compound. Of these, aromatic isocyanate compounds elute components that cannot be used in food applications in a high-temperature environment such as during heat sterilization (retort treatment). By the way, as shown in FIGS. 7 to 11, the adhesive layer is in contact with the resin film 10 constituting the inner surface 20x of the laminated body 20. Therefore, when the adhesive layer contains an aromatic isocyanate compound, the components eluted from the aromatic isocyanate compound may adhere to the contents of the bag 40 composed of the laminate 20.

In consideration of such problems, a cured product produced by reacting a polyol as a main agent with an aliphatic isocyanate compound as a curing agent is used as an adhesive constituting the adhesive layer. This makes it possible to prevent components that cannot be used in food applications from adhering to the contents due to the adhesive layer. Examples of the aliphatic isocyanate include hexamethylene diisocyanate (HDI) and isophorone diisocyanate (IPDI).

Further, by increasing the molar ratio of the isocyanate group of the aliphatic isocyanate compound to the hydroxy group of the polyol, the drop impact resistance can be enhanced. For example, the molar ratio of the curing agent (aliphatic isocyanate compound) to the hydroxy group of the main agent (polyol) is conventionally about 3. In the present embodiment, the molar ratio of the isocyanate group of the aliphatic isocyanate compound to the hydroxy group of the polyol is preferably 3.5 or more, more preferably 4 or more, and 4.5 or more. Is more preferable. More preferably, the molar ratio of the isocyanate group of the aliphatic isocyanate compound to the hydroxy group of the polyol is larger than 5.

On the other hand, the aliphatic isocyanate compound is expensive, and increasing the amount of the aliphatic isocyanate compound is not preferable in terms of production cost. Further, the larger the molar ratio of the isocyanate group of the aliphatic isocyanate compound to the hydroxy group of the polyol, the higher the temperature required for curing the adhesive composition or the longer the time. In consideration of these points, the molar ratio of the aliphatic isocyanate group to the hydroxy group is preferably 7 or less, and more preferably 6 or less.

The adhesive layer applies the adhesive composition to a first biaxially stretched plastic film, a second biaxially stretched plastic film, a metal foil or a resin film, after which the adhesive composition dries and adheres. It is formed by the reaction between the main agent in the agent composition and the solvent to cure the adhesive composition. In the present embodiment, the weight of the dried adhesive composition per unit area is preferably, for example, 2 g / m ² or more and 5 g / m ² or less, and 3 g / m ² or more and 4 g / m ² or less. It is more preferable to do so. The thickness of the adhesive layer 60 is preferably 2 μm or more and 5 μm or less, and more preferably 3 μm or more and 4 μm or less.

(First adhesive resin layer and second adhesive resin layer)
The adhesive resin layer such as the first adhesive resin layer and the second adhesive resin layer contains a thermoplastic resin for adhering the first biaxially stretched plastic film, the second biaxially stretched plastic film, and the like to each other. The adhesive resin layer is formed by a melt extrusion laminating method using a thermoplastic resin. As the thermoplastic resin that can be used for the adhesive resin layer, the same material as the above-mentioned material for the thermoplastic resin layer can be used.

(First anchor coat layer and second anchor coat layer)
Anchor coat layers such as the first anchor coat layer and the second anchor coat layer are formed to improve the adhesion of the adhesive resin layer. The anchor coat layer can be formed by applying an anchor coat agent to the surface of the layer to be laminated and drying it. Examples of the anchor coating agent include an anchor coating agent made of any resin having a heat resistant temperature of 135 ° C. or higher, for example, a vinyl-modified resin, an epoxy resin, a urethane resin, a polyester resin, or the like. An anchor coating agent composed of a polyacrylic or polymethacrylic resin having a hydroxyl group and an isocyanate compound as a curing agent can be preferably used. Further, a silane coupling agent may be used in combination with this as an additive, or nitric acid cotton may be used in combination to increase heat resistance.

(Specific example of layer structure of laminated body)
Specific examples of the laminated body 20 shown in FIGS. 7 to 11 are shown below. In addition, "/" represents the boundary between layers. The leftmost layer is a layer forming the outer surface 20y of the laminated body 20, and the rightmost layer is a layer forming the inner surface 20x of the laminated body 20. Further, "biaxially stretched PET film" means biaxially stretched polyethylene terephthalate film, "biaxially stretched PP film" means biaxially stretched polypropylene film, and "AC" means anchor coat layer. ..
(1) Biaxially stretched PET film / printing layer / adhesive layer / resin film (2) Biaxially stretched PET film / printing layer / adhesive layer / biaxially stretched nylon film / adhesive layer / resin film (3) Axial stretched PET film / printing layer / adhesive layer / biaxially stretched PET film / adhesive layer / resin film (4) Biaxially stretched PET film / printing layer / adhesive layer / metal foil / adhesive layer / resin film (4) 5) Biaxially stretched PET film / printing layer / adhesive layer / vapor deposition layer / biaxially stretched PET film / adhesive layer / resin film (6) Biaxially stretched polypropylene film / printing layer / AC / adhesive resin layer / vapor deposition layer / Biaxially stretched PET film / AC / Adhesive resin layer / Resin film

(Manufacturing method of laminated body)
The method for producing the laminate is not particularly limited, and the laminate can be produced by using a conventionally known method such as a dry laminating method, a melt extrusion laminating method, or a sand laminating method.

Bag Next, the bag 40 of the present invention will be described. FIG. 12 is a front view showing the bag 40 according to the present embodiment. The bag 40 includes an accommodating portion 40a for accommodating the contents. Hereinafter, the configuration of the bag 40 will be described.

The bag 40 includes an upper portion 41, a lower portion 42, and a side portion 43, and has a substantially rectangular contour in the front view. The names such as "upper part", "lower part" and "side part", and the terms such as "upper" and "lower" refer to the relative positions and directions of the bag 40 and its components. Not too much. The posture during transportation and use of the bag 40 is not limited by the names and terms in the present specification.

As shown in FIG. 12, the bag 40 includes a front surface film 44 that constitutes the front surface and a back surface film 45 that constitutes the back surface. The front surface film 44 and the back surface film 45 are each composed of the above-mentioned laminate 20.

The terms "front surface film" and "back surface film" described above are merely those in which each film is partitioned according to the positional relationship, and the method of providing the film when manufacturing the bag 40 is limited by the above terms. Will not be done. For example, the bag 40 may be manufactured by using one film in which the front surface film 44 and the back surface film 45 are connected in series.

The inner surfaces of the front surface film 44 and the back surface film 45 are joined by a sealing portion. In the front view of the bag 40 shown in FIG. 12, the seal portion is hatched.

As shown in FIG. 12, the sealing portion has an outer edge sealing portion extending along the outer edge of the bag 40. The outer edge seal portion includes an upper seal portion 41a extending along the upper 41, a lower seal portion 42a extending along the lower 42, and a pair of side seal portions 43a extending along the pair of side portions 43. In the bag 40 in the state before the contents are filled (the state in which the contents are not filled), an opening (not shown) is formed in the upper portion 41 of the bag 40. Then, after the contents are contained in the bag 40, the inner surface of the front surface film 44 and the inner surface of the back surface film 45 are joined at the upper portion 41 to form the upper sealing portion 41a and seal the bag 40.

The upper seal portion 41a, the lower seal portion 42a, and the side seal portion 43a are seal portions formed by joining the inner surface of the front surface film 44 and the inner surface of the back surface film 45.

As long as the films facing each other can be joined to seal the bag 40, the method for forming the sealing portion is not particularly limited. For example, the inner surface of the film may be melted by heating or the like and the inner surfaces may be welded to each other, that is, the seal portion may be formed by heat sealing.

(Easy opening means)
The front surface film 44 and the back surface film 45 may be provided with an easy-to-open means 47 for tearing the front surface film 44 and the back surface film 45 to open the bag 40. For example, as shown in FIG. 12, the easy-to-open means 46 may include a notch 47 formed in the side sealing portion 43a of the bag 40, which is a starting point of tearing. Further, a half-cut line formed by laser processing, a cutter, or the like may be provided as an easy-to-open means 46 in a portion serving as a path when tearing the bag 40.

Further, although not shown, the easy-to-open means 46 may include a group of cuts and scars formed in a region of the front surface film 44 and the back surface film 45 where the seal portion is formed. The scar group may include, for example, a plurality of through holes formed to penetrate the front surface film 44 and / or the back surface film 45. Alternatively, the scar group may include a plurality of holes formed on the outer surface of the front surface film 44 and / or the back surface film 45 so as not to penetrate the front surface film 44 and / or the back surface film 45.

(Bag manufacturing method)
First, the front surface film 44 and the back surface film 45 made of the above-mentioned laminate 20 are prepared. Subsequently, the inner surfaces of the films are heat-sealed to form seal portions such as the lower seal portion 42a and the side seal portion 43a. Further, the films bonded to each other by heat sealing are cut into an appropriate shape to obtain the bag 40 shown in FIG. Subsequently, the contents are filled in the bag 40 through the opening (not shown) of the upper portion 41. The contents are, for example, chocolate and the like. After that, the upper portion 41 is heat-sealed to form the upper seal portion 41a. In this way, the bag 40 in which the contents are contained and sealed can be obtained.

Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the description of the following Examples as long as the gist of the present invention is not exceeded.

[Example 1-1]
As a raw material for the resin composition constituting the first layer, a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , Biomass degree: 0%) was melted.
Next, as a raw material for the resin composition constituting the second layer, 85 parts by mass of a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density). : 910 kg / m ³ , polymer degree: 0%) and 15 parts by mass of biomass linear low density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³ , biomass degree: 87%) and was separately melted.
These melts were co-extruded with a T-die to prepare an unstretched resin film having a layer thickness ratio of 1: 4 (first layer: second layer) and a thickness of 50 μm. The polypropylene content in the resin film was 88% by mass, and the biomass degree of the resin film was 10%.

Next, as the first biaxially stretched plastic film 21, a biaxially stretched polyethylene terephthalate film having a thickness of 12 μm (manufactured by Toyobo Co., Ltd., product name: E5100) was prepared. Subsequently, the print layer 22 was formed on the first biaxially stretched plastic film 21. The thickness of the print layer 22 was 1.0 μm. Further, as the second biaxially stretched plastic film 24, a biaxially stretched polyethylene terephthalate film having a thickness of 12 μm (manufactured by Toyobo Co., Ltd., product name: E5100) was prepared.

Subsequently, by the dry laminating method, the first biaxially stretched plastic film 21, the printing layer 22, the first adhesive layer 23, the second biaxially stretched plastic film 24, the second adhesive layer 25, and the resin film. 10 were laminated in order to prepare a laminated body 20 shown in FIG. As the first adhesive layer 23 and the second adhesive layer 25, a two-component polyurethane adhesive (main agent: RU-40, curing agent: H-4) manufactured by Rock Paint Co., Ltd. was used. The main agent, RU-40, is a polyester polyol. The thickness of the first adhesive layer 23 and the second adhesive layer 25 was 3.0 μm, respectively. In the laminated body 20, the first layer of the resin film 10 constitutes the innermost layer.

Next, the bag 40 shown in FIG. 12 was produced. Specifically, first, a front surface film 44 and a back surface film 45 were produced from the obtained laminate 20. Next, the front surface film 44 and the back surface film 45 were superposed so that the resin film 10 of the front surface film 44 and the resin film 10 of the back surface film 45 were in contact with each other.

Then, the upper seal portion 41a, the lower seal portion 42a, and the side seal portion 43a were formed by heat sealing according to the shape of each bag 40. The heat seal was performed under the following conditions.
(Heat seal condition)
-Heat seal device: Heat sealer (manufactured by Tester Sangyo Co., Ltd., product name: TP-701-A)
-Heat seal temperature: 200 ° C, 190 ° C, 180 ° C, 170 ° C, 160 ° C, 150 ° C
・ Heat seal pressure: 0.1 MPa
・ Heat seal time: 1 second

Next, the bag 40 shown in FIG. 14 was produced by cutting the heat-sealed region according to the shape of each bag 40. Further, in the prepared bag 40, a notch 47 was formed as an easy-to-open means 46.

In the produced bag 40, the height S1 (see FIG. 12) is 140 mm, the width S2 is 120 mm, the width S3 of the upper seal portion 41a, the width S4 of the lower seal portion 42a, and the width S5 of the side seal portion 43a are 5. It was 0.0 mm.

[Example 1-2]
80 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the second layer. / ^{M 3} , polymer degree: 0%) and 20 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³⁾ , Biomass degree: 87%), and a resin film was prepared in the same manner as in Example 1-1. The layer thickness ratio was 1: 4 (first layer: second layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 84% by mass, and the biomass content of the resin film was 14%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 1-1.

[Example 1-3]
70 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the second layer. / ^{m 3,} biomass degree: 0%), 30 parts by weight of the biomass linear low density polyethylene (Braskem Inc., product name: SLL-318, MFR: 2.7g / 10 minutes, density: 918 kg / ^{m 3} , Biomass degree: 87%), and a resin film was prepared in the same manner as in Example 1-1. The layer thickness ratio was 1: 4 (first layer: second layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 76% by mass, and the biomass degree of the resin film was 21%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 1-1.

[Example 1-4]
90 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the first layer. / ^{M 3} , polymer degree: 0%) and 10 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³ , Biomass degree: 87%), and as a raw material for the resin composition constituting the second layer, 70 parts by mass of a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , polymer degree: 0%) and 30 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR). A resin film was prepared in the same manner as in Example 1-1, except that 2.7 g / 10 minutes, density: 918 kg / m ^{3, and polymer degree: 87%) were used.} The layer thickness ratio was 1: 4 (first layer: second layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 74% by mass, and the biomass degree of the resin film was 23%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 1-1.

[Example 1-5]
85 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the second layer. / ^{M 3} , polymer degree: 0%) and 15 parts by mass of biomass low density polyethylene (manufactured by Braskem, product name: SEB-853, MFR: 2.7 g / 10 minutes, density: 923 kg / m ³ , biomass degree : 95%) was used, but a resin film was produced in the same manner as in Example 1-1. The layer thickness ratio was 1: 4 (first layer: second layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 88% by mass, and the biomass degree of the resin film was 11%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 1-1.

[Example 1-6]
70 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the second layer. / ^{M 3} , polymer degree: 0%) and 30 parts by mass of biomass low density polyethylene (manufactured by Braskem, product name: SEB-853, MFR: 2.7 g / 10 minutes, density: 923 kg / m ³ , biomass degree : 95%) was used, but a resin film was produced in the same manner as in Example 1-1. The layer thickness ratio was 1: 4 (first layer: second layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 76% by mass, and the biomass degree of the resin film was 23%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 1-1.

[Example 1-7]
As a raw material for the resin composition constituting the second layer, 70 parts by mass of propylene-ethylene block copolymer (manufactured by Prime Polymer Co., Ltd., product name: J715M, MFR: 9.0 g / 10 minutes, degree of biomass: 0%) and 30 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³ , polymer degree: 87%) A resin film was produced in the same manner as in Example 1-1 except that the above was used. The layer thickness ratio was 1: 4 (first layer: second layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 76% by mass, and the biomass degree of the resin film was 21%. The structure of the resin film of this example is shown in Table 1.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 1-1.

[Comparative Example 1-1]
Only propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , biomass degree: 0%) is melted and melted. Was extruded with a T-die to prepare an unstretched resin film having a thickness of 50 μm.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 1-1.

[Comparative Example 1-2]
Only the propylene-ethylene block copolymer (manufactured by Prime Polymer Co., Ltd., product name: J715M, MFR: 9.0 g / 10 minutes, biomass degree: 0%) is melted, and the melt is extruded with a T-die. , An unstretched resin film having a thickness of 50 μm was prepared.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 1-1.

[Comparative Example 1-3]
70 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the first layer. / ^{M 3} , polymer degree: 0%) and 30 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³⁾ , Biomass degree: 87%), and as a raw material for the resin composition constituting the second layer, 70 parts by mass of a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , polymer degree: 0%) and 30 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR). A resin film was prepared in the same manner as in Example 1-1, except that 2.7 g / 10 minutes, density: 918 kg / m ^{3, and polymer degree: 87%) were used.} The layer thickness ratio was 1: 4 (first layer: second layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 70% by mass, and the biomass content of the resin film was 26%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 1-1.

[Comparative Example 1-4]
As a raw material for the resin composition constituting the first layer, a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , Biomass degree: 0%) was melted.
Next, as a raw material for the resin composition constituting the second layer, 60 parts by mass of a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density). : 910 kg / m ³ , polymer degree: 0%) and 40 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³ , biomass degree: 87%) and was separately melted.
These melts were co-extruded with a T-die, but the resin composition could not be formed into a film.

The details of each layer and the details of the resin film according to Examples 1-1 to 1-7 and Comparative Examples 1-1 to 1-4 are shown in Tables 1 and 2. In Table 1, "petrified random PP" means a propylene-ethylene random copolymer, "petrified block PP" means a propylene-ethylene block copolymer, and "bio-LLDPE" means a biomass linear low-density polyethylene. Means, "bio-LDPE" means biomass low density polyethylene. The contents in Tables 1 and 2 are all based on mass.

[Example 2-1]
As a raw material for the resin composition constituting the first layer, a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , Biomass degree: 0%) was melted.
Next, as a raw material for the resin composition constituting the second layer, 80 parts by mass of a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density). : 910 kg / m ³ , polymer degree: 0%) and 20 parts by mass of biomass linear low density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³ , biomass degree: 87%) and was separately melted.
Next, as a raw material for the resin composition constituting the third layer, a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m). ^3. Biomass degree: 0%) was separately melted.
These melts were co-extruded with a T-die to prepare an unstretched resin film having a layer thickness ratio of 1: 3: 1 (first layer: second layer: third layer) and a thickness of 50 μm. The polypropylene content in the resin film was 88% by mass, and the biomass degree of the resin film was 10%.

Next, as the first biaxially stretched plastic film 21, a biaxially stretched polyethylene terephthalate film having a thickness of 12 μm (manufactured by Toyobo Co., Ltd., product name: E5100) was prepared. Subsequently, the print layer 22 was formed on the first biaxially stretched plastic film 21. The thickness of the print layer 22 was 1.0 μm. Further, as the second biaxially stretched plastic film 24, a biaxially stretched polyethylene terephthalate film having a thickness of 12 μm (manufactured by Toyobo Co., Ltd., product name: E5100) was prepared.

Subsequently, by the dry laminating method, the first biaxially stretched plastic film 21, the printing layer 22, the first adhesive layer 23, the second biaxially stretched plastic film 24, the second adhesive layer 25, and the resin film. 10 were laminated in order to prepare a laminated body 20 shown in FIG. As the first adhesive layer 23 and the second adhesive layer 25, a two-component polyurethane adhesive (main agent: RU-40, curing agent: H-4) manufactured by Rock Paint Co., Ltd. was used. The main agent, RU-40, is a polyester polyol. The thickness of the first adhesive layer 23 and the second adhesive layer 25 was 3.0 μm, respectively. In the laminated body 20, the first layer of the resin film 10 constitutes the innermost layer.

Next, the bag 40 shown in FIG. 12 was produced. Specifically, first, a front surface film 44 and a back surface film 45 were produced from the obtained laminate 20. Next, the front surface film 44 and the back surface film 45 were superposed so that the resin film 10 of the front surface film 44 and the resin film 10 of the back surface film 45 were in contact with each other.

Then, the upper seal portion 41a, the lower seal portion 42a, and the side seal portion 43a were formed by heat sealing according to the shape of each bag 40. The heat seal was performed under the following conditions.
(Heat seal condition)
-Heat seal device: Heat sealer (manufactured by Tester Sangyo Co., Ltd., product name: TP-701-A)
-Heat seal temperature: 200 ° C, 190 ° C, 180 ° C, 170 ° C, 160 ° C, 150 ° C
・ Heat seal pressure: 0.1 MPa
・ Heat seal time: 1 second

Next, the bag 40 shown in FIG. 14 was produced by cutting the heat-sealed region according to the shape of each bag 40. Further, in the prepared bag 40, a notch 47 was formed as an easy-to-open means 46.

In the produced bag 40, the height S1 (see FIG. 12) is 140 mm, the width S2 is 120 mm, the width S3 of the upper seal portion 41a, the width S4 of the lower seal portion 42a, and the width S5 of the side seal portion 43a are 5. It was 0.0 mm.

[Example 2-2]
70 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the second layer. / ^{m 3,} biomass degree: 0%), 30 parts by weight of the biomass linear low density polyethylene (Braskem Inc., product name: SLL-318, MFR: 2.7g / 10 minutes, density: 918 kg / ^{m 3} , Biomass degree: 87%), and a resin film was prepared in the same manner as in Example 2-1. The layer thickness ratio was 1: 3: 1 (first layer: second layer: third layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 82% by mass, and the biomass content of the resin film was 16%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 2-1.

[Example 2-3]
90 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the first layer. / ^{M 3} , polymer degree: 0%) and 10 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³ , Biomass degree: 87%), and as a raw material for the resin composition constituting the second layer, 70 parts by mass of a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , polymer degree: 0%) and 30 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR). A resin film was prepared in the same manner as in Example 2-1 except that 2.7 g / 10 minutes, density: 918 kg / m ^{3, and polymer degree: 87%) were used.} The layer thickness ratio was 1: 3: 1 (first layer: second layer: third layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 80% by mass, and the biomass degree of the resin film was 17%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 2-1.

[Example 2-4]
90 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the first layer. / ^{m 3,} biomass degree: 0%), 10 parts by weight of biomass linear low density polyethylene (Braskem Inc., product name: SLL-318, MFR: 2.7g / 10 minutes, density: 918 kg / ^{m 3} , Biomass degree: 87%), and 70 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA) as a raw material for the resin composition constituting the second layer. , MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , polymer degree: 0%) and 30 parts by mass of biomass linear low density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³ , biomass degree: 87%), and 80 parts by mass of propylene-ethylene random common weight as a raw material for the resin composition constituting the third layer. Combined (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , biomass degree: 0%) and 20 parts by mass of biomass linear low-density polyethylene. (Manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³ , polymer degree: 87%), except that the same as in Example 2-1 was used. To prepare a resin film. The layer thickness ratio was 1: 3: 1 (first layer: second layer: third layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 76% by mass, and the biomass degree of the resin film was 21%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 2-1.

[Example 2-5]
80 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the second layer. / ^{M 3} , polymer degree: 0%) and 20 parts by mass of biomass low density polyethylene (manufactured by Braskem, product name: SEB-853, MFR: 2.7 g / 10 minutes, density: 923 kg / m ³ , biomass degree : 95%) was used, but a resin film was produced in the same manner as in Example 2-1. The layer thickness ratio was 1: 3: 1 (first layer: second layer: third layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 88% by mass, and the biomass degree of the resin film was 11%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 2-1.

[Example 2-6]
70 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the second layer. / ^{M 3} , polymer degree: 0%) and 30 parts by mass of biomass low density polyethylene (manufactured by Braskem, product name: SEB-853, MFR: 2.7 g / 10 minutes, density: 923 kg / m ³ , biomass degree : 95%) was used, but a resin film was produced in the same manner as in Example 2-1. The layer thickness ratio was 1: 3: 1 (first layer: second layer: third layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 82% by mass, and the biomass degree of the resin film was 17%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 2-1.

[Example 2-7]
A propylene-ethylene block copolymer (manufactured by Prime Polymer Co., Ltd., product name: J715M, MFR: 9.0 g / 10 minutes, biomass degree: 0%) was used as a raw material for the resin composition constituting the first layer. 70 parts by mass of propylene-ethylene block copolymer (manufactured by Prime Polymer Co., Ltd., product name: J715M, MFR: 9.0 g / 10 minutes) as a raw material for the resin composition constituting the second layer. , Polymer degree: 0%) and 30 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³ , polymer degree : 87%) and as a raw material for the resin composition constituting the third layer, a propylene-ethylene block copolymer (manufactured by Prime Polymer Co., Ltd., product name: J715M, MFR: 9.0 g) A resin film was prepared in the same manner as in Example 2-1 except that the degree of biomass: 0% was used for 10 minutes. The layer thickness ratio was 1: 3: 1 (first layer: second layer: third layer), and the thickness of the resin film was 50 μm. The polypropylene content of the resin film was 82% by mass, and the biomass content in the resin film was 16%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 2-1.

[Comparative Example 2-1]
Only propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , biomass degree: 0%) is melted and melted. Was extruded with a T-die to prepare an unstretched resin film having a thickness of 50 μm.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 2-1.

[Comparative Example 2-2]
Only the propylene-ethylene block copolymer (manufactured by Prime Polymer Co., Ltd., product name: J715M, MFR: 9.0 g / 10 minutes, biomass degree: 0%) is melted, and the melt is extruded with a T-die. , An unstretched resin film having a thickness of 50 μm was prepared.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 2-1.

[Comparative Example 2-3]
70 parts by mass of propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg) as a raw material for the resin composition constituting the first layer. / ^{M 3} , polymer degree: 0%) and 30 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³⁾ , Biomass degree: 87%), and as a raw material for the resin composition constituting the second layer, 70 parts by mass of a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , polymer degree: 0%) and 30 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR). A resin film was prepared in the same manner as in Example 2-1 except that 2.7 g / 10 minutes, density: 918 kg / m ^{3, and polymer degree: 87%) were used.} The layer thickness ratio was 1: 3: 1 (first layer: second layer: third layer), and the thickness of the resin film was 50 μm. The polypropylene content in the resin film was 76% by mass, and the biomass degree of the resin film was 21%.
Further, using the obtained resin film, a laminate and a bag were produced in the same manner as in Example 2-1.

[Comparative Example 2-4]
As a raw material for the resin composition constituting the first layer, a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m ³ , Biomass degree: 0%) was melted.
Next, as a raw material for the resin composition constituting the second layer, 60 parts by mass of a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density). : 910 kg / m ³ , polymer degree: 0%) and 40 parts by mass of biomass linear low-density polyethylene (manufactured by Braskem, product name: SLL-318, MFR: 2.7 g / 10 minutes, density: 918 kg / m ³ , biomass degree: 87%) and was separately melted.
Next, as a raw material for the resin composition constituting the third layer, a propylene-ethylene random copolymer (manufactured by Prime Polymer Co., Ltd., product name: F219DA, MFR: 8.0 g / 10 minutes, density: 910 kg / m). ^3. Biomass degree: 0%) was separately melted.
These melts were co-extruded with a T-die, but the resin composition could not be formed into a film.

The details of each layer and the details of the resin film according to Examples 2-1 to 2-7 and Comparative Examples 2-1 to 2-4 are shown in Tables 3 and 4. In Table 3, "petrified random PP" means a propylene-ethylene random copolymer, "petrified block PP" means a propylene-ethylene block copolymer, and "bio-LLDPE" means a biomass linear low-density polyethylene. Means, "bio-LDPE" means biomass low density polyethylene. The contents in Tables 3 and 4 are all based on mass.

<< Seal strength test >>
Bags according to Examples 1-1 to 1-7 and Comparative Examples 1-1 to 1-3, and Examples 2-1 to 2-7 and Comparative Examples 2-1 to 2-3 having a heat seal temperature of 200 ° C. A seal strength test was performed using 40. The seal strength was measured in an environment of a temperature of 25 ° C. and a relative humidity of 50% in accordance with JIS Z 0238: 1998, and a tensile tester: SA-1150 manufactured by Orientec Co., Ltd. was used as a measuring instrument. Specifically, as shown in FIG. 13, a rectangular test piece 50 having a side S6 of 15 mm and an other side S7 extending in a direction orthogonal to one side of 50 mm was cut out so as to include the side seal portion 43a. Subsequently, as shown in FIG. 14, the unsealed portion of the front surface film 44 and the unsealed portion of the back surface film 45 in the test piece 50 are oriented in opposite directions in the direction orthogonal to the surface direction of the sealed portion. That is, after forming a T-shape, the end portion of the non-seal portion of the front surface film 44 and the end portion of the non-seal portion of the back surface film 45 were fixed to the grippers 51 and 52, respectively. With the chuck distance (S8) set to 50 mm, the respective grippers 51 and 52 are pulled in the opposite directions in the direction orthogonal to the surface direction of the seal portion of the test piece 50 at a speed of 300 mm / min, and the tensile stress is applied. Measure the maximum value of. This operation is performed a total of 5 times using the test pieces 50 cut out from different bags 40, and the average value of the maximum values of the 5 times tensile stress is taken as the seal strength. The evaluation results are shown in Tables 5 and 6.
(Evaluation criteria)
-Good: The seal strength was 40 N / 15 mm or more.
-Yes: The seal strength was 20 N / 15 mm or more and less than 40 N / 15 mm.
-Not possible: The seal strength was less than 20 N / 15 mm.

<< Low temperature sealability test >>
Examples 1-1 to 1-7 and Comparative Examples 1-1 to 1-3, and Examples 2-1 to 2-7, where the heat seal temperature is 150 ° C., 160 ° C., 170 ° C., 180 ° C. and 190 ° C. A low temperature sealability test was conducted using the bags 40 according to Comparative Examples 2-1 to 2-3, respectively. In the low-temperature sealability test, as in the seal strength test, the seal strength is measured in an environment with a temperature of 25 ° C and a relative humidity of 50% in accordance with JIS Z 0238: 1998. Tensile tester: SA-1150 was used. Specifically, as shown in FIG. 13, a rectangular test piece 50 having a side S6 of 15 mm and an other side S7 extending in a direction orthogonal to one side of 50 mm was cut out so as to include the side seal portion 43a. Subsequently, as shown in FIG. 14, the unsealed portion of the front surface film 44 and the unsealed portion of the back surface film 45 in the test piece 50 are oriented in opposite directions in the direction orthogonal to the surface direction of the sealed portion. That is, after forming a T-shape, the end portion of the non-seal portion of the front surface film 44 and the end portion of the non-seal portion of the back surface film 45 were fixed to the grippers 51 and 52, respectively. With the chuck distance (S8) set to 50 mm, the respective grippers 51 and 52 are pulled in the opposite directions in the direction orthogonal to the surface direction of the seal portion of the test piece 50 at a speed of 300 mm / min, and the tensile stress is applied. Measure the maximum value of. This operation is performed a total of 5 times using the test pieces 50 cut out from different bags 40, and the average value of the maximum values of the 5 times tensile stress is taken as the seal strength. The evaluation results are shown in Tables 5 and 6.
(Evaluation criteria)
Good: In a bag having a heat seal temperature of 150 ° C. or higher, the seal strength was 20 N / 15 mm or higher.
Possible: In a bag having a heat seal temperature of 170 ° C. or higher, the seal strength was 20 N / 15 mm or higher.
Impossible: The seal strength was less than 20 N / 15 mm in a bag having a heat seal temperature of 190 ° C.

<< Tearability test >>
Bags according to Examples 1-1 to 1-7 and Comparative Examples 1-1 to 1-3, and Examples 2-1 to 2-7 and Comparative Examples 2-1 to 2-3 having a heat seal temperature of 200 ° C. A tearability test was performed using 40. In the tearability test, the sample is held by the left hand so that the notch 47 of the bag 40 of each example and the comparative example is on the left side and sideways, and the bag 40 is torn by pulling the bag 40 toward the front with the right hand while keeping the left hand fixed. Was done by. The evaluation results are shown in Tables 5 and 6.
(Evaluation criteria)
-Good: The bag 40 could be torn linearly.
-Yes: Although it is not straight, the bag 40 could be torn.
-No: The bag 40 could not be torn.

<< Evaluation of film-forming property >>
The film-forming property was evaluated in Examples 1-1 to 1-7 and Comparative Examples 1-1 to 1-4, and Examples 2-1 to 2-7 and Comparative Examples 2-1 to 2-4. Judgment was made based on the possibility of film formation. The evaluation results are shown in Tables 5 and 6.
(Evaluation criteria)
-Good: The resin composition was made into a film.
-No: The resin composition could not be made into a film.

As is clear from the above table, the resin film, laminate and bag of the present invention have an environmental load reducing property, a sealing property and a film forming property, and are also excellent in tearing property.

10 Resin film 11 1st layer 12 2nd layer 13 1st thermoplastic resin layer 14 3rd layer 15 2nd thermoplastic resin layer 20 Laminated body 20x Inner surface 20y Outer surface 21 1st biaxially stretched plastic film 22 Printing layer 23 First adhesive layer 24 Second biaxially stretched plastic film 25 Second adhesive layer 26 Metal foil 27 Vapor deposition layer 28 First anchor coat layer 29 First adhesive resin layer 30 Second anchor coat layer 31 Second adhesive resin layer 40 Bag 40a Storage part 41 Upper 41a Upper seal part 42 Lower 42a Lower seal part 43 Side 43a Side seal 44 Front film 45 Back film 46 Easy-to-open means 47 Notch 50 Test piece 51, 52 Grip

Claims (8)

A resin film having at least two layers, a first layer and a second layer.
The first layer and the second layer are laminated either directly or via a thermoplastic resin layer.
The first layer constitutes the innermost layer of the resin film.
The resin film contains polypropylene and polyethylene, and the resin film contains polypropylene and polyethylene.
The resin composition constituting the first layer contains polypropylene as a main component and contains polypropylene.
The content of polyethylene in the first layer is 20% by mass or less, and the content is 20% by mass or less.
The resin composition constituting the second layer contains polypropylene as a main component and biomass polyethylene.
A resin film having a polyethylene content of the second layer of 35% by mass or less. The resin film further comprises a third layer.
The third layer is laminated to the second layer directly or via a thermoplastic resin layer.
The resin composition constituting the third layer contains polypropylene as a main component and contains polypropylene.
The resin film according to claim 1, wherein the content of polyethylene in the third layer is 35% by mass or less. The resin film according to claim 1 or 2, wherein the biomass degree is 5% or more. The resin film according to any one of claims 1 to 3, wherein the layer constituting the outermost layer of the resin film has a biomass degree of 30% or less. The resin film according to any one of claims 1 to 4, wherein the polypropylene content is 66% by mass or more. The resin film according to any one of claims 1 to 5, wherein the elongation at break in one direction and the other direction orthogonal to the one direction are 500% or more, respectively. A laminate comprising at least one biaxially stretched plastic film and the resin film according to any one of claims 1 to 6. A bag comprising the laminate according to claim 7.

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