JP2024117810A - Laminate with biomass-derived resin layer - Google Patents

Abstract

[Problem] To provide a laminate having a biomass polyolefin resin layer containing a carbon-neutral polyolefin using ethylene derived from biomass. [Solution] The laminate for packaging products according to the present invention comprises a fossil fuel polyester resin layer made of a fossil fuel polyester resin composition containing, as a main component, a polyester composed of diol units derived from fossil fuels and dicarboxylic acid units derived from fossil fuels, a barrier layer containing inorganic matter, a biomass polyolefin resin layer made of a biomass polyolefin resin composition containing biomass-derived polyethylene obtained by polymerizing a monomer containing ethylene derived from biomass, and a non-biomass polyolefin resin layer made of a resin material containing a raw material derived from fossil fuels, and has two or more non-biomass polyolefin resin layers including the above, and the resin constituting at least one of the non-biomass polyolefin resin layers is polypropylene. [Selected Figure] Figure 1

Description

The present invention relates to a laminate having a biomass-derived resin layer, and more specifically, to a laminate having a biomass polyester resin layer containing a biomass polyester whose diol units are biomass-derived ethylene glycol, and a biomass polyolefin resin layer containing a biomass-derived polyolefin formed by polymerization of a monomer containing biomass-derived ethylene.

In recent years, as calls for the creation of a recycling-oriented society grow, there is a desire to move away from fossil fuels in the materials field, just as there is in the energy field, and the use of biomass has attracted attention. Biomass is an organic compound produced by photosynthesis from carbon dioxide and water, and by using it, it becomes carbon dioxide and water again, making it a so-called carbon-neutral renewable energy. Recently, the practical application of biomass plastics made from these biomass raw materials has progressed rapidly, and attempts are also being made to produce various resins from biomass raw materials.

As for biomass-derived resins, polylactic acid (PLA), which is manufactured via lactic acid fermentation, was the first to be commercially produced; however, since its performance as a plastic differs significantly from current general-purpose plastics, including its biodegradability, there are limitations to its product applications and manufacturing methods, and it has not yet come into widespread use. Furthermore, a life cycle assessment (LCA) is being carried out on PLA, and discussions are being held on the energy consumption during PLA manufacturing and its equivalence as an alternative to general-purpose plastics.

Here, various types of general-purpose plastics are used, including polyethylene, polypropylene, polyvinyl chloride, and polystyrene. In particular, polyethylene is molded into films, sheets, bottles, etc. and is used in a variety of applications, such as packaging material, and is used in large quantities around the world. For this reason, using conventional polyethylene derived from fossil fuels places a large burden on the environment.

Therefore, it is desirable to use biomass-derived raw materials in the production of polyethylene to reduce the amount of fossil fuels used. For example, research has been conducted to date on the production of ethylene and butylene, the raw materials for polyolefin resins, from renewable natural raw materials (see, for example, Patent Document 1).

Special Publication No. 2011-506628

The present inventors focused on ethylene, a raw material for polyolefin laminates, and discovered that a laminate having a biomass polyolefin resin layer made of polyolefin using ethylene derived from biomass as its raw material instead of ethylene obtained from conventional fossil fuels has physical properties such as mechanical properties that are comparable to those of a polyolefin resin laminate produced using ethylene obtained from conventional fossil fuels. The present invention is based on this discovery.

Therefore, the object of the present invention is to provide a laminate having a biomass polyolefin resin layer containing a carbon-neutral polyolefin using ethylene derived from biomass, and to provide a laminate having a biomass resin layer that is comparable in terms of physical properties such as mechanical properties to a laminate having a polyolefin resin layer produced from raw materials obtained from conventional fossil fuels.

In an embodiment of the present invention,
a fossil fuel polyester resin layer made of a fossil fuel polyester resin composition containing, as a main component, a polyester composed of a fossil fuel-derived diol unit and a fossil fuel-derived dicarboxylic acid unit;
A barrier layer including an inorganic material;
A biomass polyolefin resin layer made of a biomass polyolefin resin composition containing biomass-derived polyethylene obtained by polymerizing a monomer containing ethylene derived from biomass;
A non-biomass polyolefin resin layer made of a resin material containing a raw material derived from a fossil fuel;
and
It has two or more non-biomass polyolefin resin layers, including the above-mentioned ones,
There is provided a laminate for packaging products, wherein the resin constituting at least one of the non-biomass polyolefin resin layers is polypropylene.
In another aspect of the present invention, the barrier layer preferably includes a vapor-deposited film of an inorganic substance or an inorganic oxide.
In a further aspect of the present invention, the biomass polyolefin resin layer preferably contains biomass-derived low-density polyethylene and/or biomass-derived linear low-density polyethylene.
In a further aspect of the present invention, the biomass polyolefin resin layer preferably contains 5 mass % or more of ethylene derived from the biomass based on the entirety of the biomass polyolefin resin layer.
In another aspect of the present invention, there is provided a packaging product comprising the above-mentioned laminate for packaging products.

The laminate according to the present invention has a biomass polyolefin resin layer made of a biomass polyolefin resin composition containing biomass-derived polyethylene formed by polymerizing a monomer containing biomass-derived ethylene, thereby realizing a laminate having a carbon-neutral biomass resin layer. Therefore, the amount of fossil fuel used can be significantly reduced compared to conventional methods, and the environmental load can be reduced. In addition, the laminate according to the present invention is comparable in physical properties such as mechanical properties to conventional laminates made of resins produced from raw materials obtained from fossil fuels, and can therefore replace conventional resin laminates.

FIG. 1 is a schematic cross-sectional view showing an example of a laminate according to the present invention. FIG. 1 is a schematic cross-sectional view showing an example of a laminate according to the present invention.

In the present invention, the terms "biomass polyester resin composition," "biomass polyester resin layer," "biomass polyolefin resin composition," and "biomass polyolefin resin layer" refer to compositions that use at least a portion of their raw materials derived from biomass, but do not mean that all of the raw materials are derived from biomass.

The laminate according to the present invention is composed of a biomass polyester resin composition mainly composed of a polyester consisting of diol units and dicarboxylic acid units, and the diol units are ethylene glycol derived from biomass. Alternatively, the laminate is composed of a fossil fuel biomass polyester resin layer composed of a fossil fuel polyester resin composition mainly composed of a polyester consisting of diol units derived from fossil fuels and dicarboxylic acid units derived from fossil fuels, and a biomass polyolefin resin layer. By having the biomass polyolefin resin layer, the laminate can realize a carbon-neutral polyolefin resin laminate. Therefore, the amount of fossil fuel used can be significantly reduced compared to the conventional method, and the environmental load can be reduced. In addition, the laminate according to the present invention is comparable in physical properties such as mechanical properties to conventional polyolefin resin laminates manufactured from raw materials obtained from fossil fuels, and can therefore replace conventional polyolefin resin laminates.

Schematic cross-sectional views of an example of a laminate according to the present invention are shown in Figures 1 and 2. The laminate 10 shown in Figure 1 comprises a biomass polyester resin layer 11 and a biomass polyolefin resin layer 12 formed on the biomass polyester resin layer 11. The laminate 20 shown in Figure 2 comprises a biomass polyester resin layer 21, a first biomass polyolefin resin layer 22 formed on the biomass polyester resin layer 21, and a second biomass polyolefin resin layer 23 formed on the first biomass polyolefin resin layer 22, in this order. Each layer constituting the laminate will be described below.

Biomass polyester resin layer In the present invention, the biomass polyester resin layer is made of the following biomass polyester resin composition containing, as a main component, a polyester composed of diol units and dicarboxylic acid units.

Biomass polyester The biomass polyester contained in the biomass polyester resin composition is composed of a diol unit and a dicarboxylic acid unit, and the diol unit is ethylene glycol derived from biomass. The dicarboxylic acid unit may be a dicarboxylic acid derived from a fossil fuel. The biomass polyester can be obtained by a polycondensation reaction using such ethylene glycol derived from biomass and a dicarboxylic acid derived from a fossil fuel.

Biomass-derived ethylene glycol is made from ethanol (biomass ethanol) produced from biomass as a raw material. For example, biomass-derived ethylene glycol can be obtained by converting biomass ethanol into ethylene oxide by a conventionally known method, or by other methods to produce ethylene glycol. Commercially available biomass ethylene glycol may also be used, and for example, biomass ethylene glycol available from India Glycoal Limited can be suitably used.

The dicarboxylic acid units of the biomass polyester may be dicarboxylic acids derived from fossil fuels. As the dicarboxylic acid, aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and derivatives thereof can be used without restrictions. Examples of aromatic dicarboxylic acids include terephthalic acid and isophthalic acid, and examples of derivatives of aromatic dicarboxylic acids include lower alkyl esters of aromatic dicarboxylic acids, specifically methyl esters, ethyl esters, propyl esters, and butyl esters. Among these, terephthalic acid is preferred, and as a derivative of an aromatic dicarboxylic acid, dimethyl terephthalate is preferred.

Specific examples of aliphatic dicarboxylic acids include linear or alicyclic dicarboxylic acids having 2 to 40 carbon atoms, such as oxalic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, dodecanedioic acid, dimer acid, and cyclohexanedicarboxylic acid. Examples of derivatives of aliphatic dicarboxylic acids include lower alkyl esters such as methyl esters, ethyl esters, propyl esters, and butyl esters of the above aliphatic dicarboxylic acids, and cyclic acid anhydrides of the above aliphatic dicarboxylic acids, such as succinic anhydride. Among these, adipic acid, succinic acid, dimer acid, or a mixture thereof is preferred, and those containing succinic acid as the main component are particularly preferred. Examples of derivatives of aliphatic dicarboxylic acids include methyl esters of adipic acid and succinic acid, or a mixture thereof.

These dicarboxylic acids can be used alone or in combination.

The biomass polyester may be a copolymerized biomass polyester in which a copolymerization component is added as a third component in addition to the above diol component and dicarboxylic acid component. Specific examples of the copolymerization component include bifunctional oxycarboxylic acid, and at least one polyfunctional compound selected from the group consisting of trifunctional or higher polyhydric alcohols, trifunctional or higher polycarboxylic acids and/or their anhydrides, and trifunctional or higher oxycarboxylic acids to form a crosslinked structure. Among these copolymerization components, bifunctional and/or trifunctional or higher oxycarboxylic acids are particularly preferred because they tend to easily produce copolymerized biomass polyesters with a high degree of polymerization. Among them, the use of trifunctional or higher oxycarboxylic acids is most preferred because it allows the production of biomass polyesters with a high degree of polymerization easily with a very small amount without using a chain extender, which will be described later.

The biomass polyester may be a high molecular weight biomass polyester obtained by chain-extending (coupling) these copolymerized biomass polyesters. Chain extenders such as carbonate compounds and diisocyanate compounds can also be used, but the amount is usually 10 mol % or less, preferably 5 mol % or less, and more preferably 3 mol % or less of carbonate bonds and urethane bonds relative to 100 mol % of all monomer units constituting the biomass polyester.

Specific examples of carbonate compounds include diphenyl carbonate, ditolyl carbonate, bis(chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, dimethyl carbonate, diethyl carbonate, dibutyl carbonate, ethylene carbonate, diamyl carbonate, dicyclohexyl carbonate, etc. In addition, carbonate compounds consisting of the same or different hydroxy compounds derived from hydroxy compounds such as phenols and alcohols can be used.

Specific examples of diisocyanate compounds include known diisocyanates such as 2,4-tolylene diisocyanate, a mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate.

Biomass polyester can be obtained by a conventional method of polycondensing the above-mentioned diol units and dicarboxylic acid units. Specifically, it can be produced by a general melt polymerization method in which an esterification reaction and/or transesterification reaction between the above-mentioned dicarboxylic acid component and diol component is carried out, followed by a polycondensation reaction under reduced pressure, or by a known solution heating dehydration condensation method using an organic solvent.

The amount of diol used in producing biomass polyester is essentially equimolar to 100 moles of dicarboxylic acid or its derivative, but generally, 0.1 to 20 mol % excess is used due to distillation during the esterification and/or transesterification reaction and/or condensation polymerization reaction.

The polycondensation reaction is preferably carried out in the presence of a polymerization catalyst. The timing of adding the polymerization catalyst is not particularly limited as long as it is before the polycondensation reaction, and it may be added when the raw materials are charged or when the pressure reduction starts.

Polymerization catalysts generally include compounds containing metal elements of Groups 1 to 14 of the periodic table, excluding hydrogen and carbon. Specific examples include compounds containing organic groups such as carboxylates, alkoxy salts, organic sulfonates, and β-diketonate salts containing at least one metal selected from the group consisting of titanium, zirconium, tin, antimony, cerium, germanium, zinc, cobalt, manganese, iron, aluminum, magnesium, calcium, strontium, sodium, and potassium, as well as inorganic compounds such as oxides and halides of the above metals and mixtures thereof. Among these, metal compounds containing titanium, zirconium, germanium, zinc, aluminum, magnesium, and calcium, as well as mixtures thereof, are preferred, and titanium compounds, zirconium compounds, and germanium compounds are particularly preferred. In addition, the catalyst is preferably a compound that is liquid during polymerization or that dissolves in ester oligomers or biomass polyesters, because the polymerization rate increases when the catalyst is in a molten or dissolved state during polymerization.

As the titanium compound, tetraalkyl titanates are preferred, specifically tetra-n-propyl titanate, tetraisopropyl titanate, tetra-n-butyl titanate, tetra-t-butyl titanate, tetraphenyl titanate, tetracyclohexyl titanate, tetrabenzyl titanate, and mixed titanates thereof. In addition, titanium (oxy) acetylacetonate, titanium tetraacetylacetonate, titanium (diisopropoxide) acetylacetonate, titanium bis(ammonium lactate) dihydroxide, titanium bis(ethylacetoacetate) diisopropoxide, titanium (triethanolamine) isopropoxide, polyhydroxytitanium stearate, titanium lactate, titanium triethanolamine, butyl titanate dimer, etc. are also preferably used. Furthermore, titanium oxide and composite oxides containing titanium and silicon are also preferably used. Among these, tetra-n-propyl titanate, tetraisopropyl titanate, tetra-n-butyl titanate, titanium (oxy) acetylacetonate, titanium tetraacetylacetonate, titanium bis(ammonium lactate) dihydroxide, polyhydroxytitanium stearate, titanium lactate, butyl titanate dimer, titanium oxide, titania/silica composite oxide (e.g., product name: C-94 manufactured by Acordis Industrial Fibers) are preferred, and tetra-n-butyl titanate, polyhydroxytitanium stearate, titanium (oxy) acetylacetonate, titanium tetraacetylacetonate, titania/silica composite oxide (e.g., product name: C-94 manufactured by Acordis Industrial Fibers) are particularly preferred.

Specific examples of zirconium compounds include zirconium tetraacetate, zirconium acetate hydroxide, zirconium tris(butoxy)stearate, zirconyl diacetate, zirconium oxalate, zirconyl oxalate, potassium zirconium oxalate, polyhydroxyzirconium stearate, zirconium ethoxide, zirconium tetra-n-propoxide, zirconium tetraisopropoxide, zirconium tetra-n-butoxide, zirconium tetra-t-butoxide, zirconium tributoxyacetylacetonate, and mixtures thereof. Zirconium oxide and composite oxides containing, for example, zirconium and silicon may also be used. Among these, zirconyl diacetate, zirconium tris(butoxy)stearate, zirconium tetraacetate, zirconium acetate hydroxide, ammonium zirconium oxalate, potassium zirconium oxalate, polyhydroxyzirconium stearate, zirconium tetra-n-propoxide, zirconium tetraisopropoxide, zirconium tetra-n-butoxide, and zirconium tetra-t-butoxide are preferred.

Specific examples of germanium compounds include inorganic germanium compounds such as germanium oxide and germanium chloride, and organic germanium compounds such as tetraalkoxygermanium. In view of cost and availability, germanium oxide, tetraethoxygermanium, and tetrabutoxygermanium are preferred, with germanium oxide being particularly preferred.

When using metal compounds as these polymerization catalysts, the amount of catalyst used is usually 5 ppm or more, preferably 10 ppm or more, and the upper limit is usually 30,000 ppm or less, preferably 1,000 ppm or less, more preferably 250 ppm or less, and particularly preferably 130 ppm or less, in terms of the amount of metal relative to the biomass polyester produced. If too much catalyst is used, not only is it economically disadvantageous but the thermal stability of the polymer is reduced, whereas if too little is used, the polymerization activity is reduced, and as a result, decomposition of the polymer is easily induced during polymer production. As for the amount of catalyst used here, the method of reducing the amount of catalyst used is a preferred embodiment, since the amount of terminal carboxyl groups in the biomass polyester produced is reduced as the amount of catalyst used is reduced.

The reaction temperature for the esterification reaction and/or transesterification reaction between the dicarboxylic acid component and the diol component is usually in the range of 150 to 260°C, and the reaction atmosphere is usually an inert gas atmosphere such as nitrogen or argon. The reaction pressure is usually from normal pressure to 10 kPa. The reaction time is usually about 1 to 10 hours.

In the above-mentioned manufacturing process, a chain extender (coupling agent) may be added to the reaction system. After the polycondensation is completed, the chain extender is added to the reaction system in a homogeneous molten state without a solvent, and reacted with the biomass polyester obtained by polycondensation.

High molecular weight biomass polyesters using these chain extenders (coupling agents) can be produced using known techniques. After polycondensation is completed, the chain extender is added to the reaction system in a homogeneous molten state without a solvent, and reacted with the biomass polyester obtained by polycondensation. Specifically, a biomass polyester prepolymer obtained by catalytic reaction of a diol with a dicarboxylic acid, which has a terminal group that substantially has a hydroxyl group and has a mass average molecular weight (Mw) of 20,000 or more, preferably 40,000 or more, can be reacted with the chain extender to obtain a biomass polyester resin with a higher molecular weight. If the prepolymer has a mass average molecular weight of 20,000 or more, a small amount of coupling agent can be used to produce a high molecular weight biomass polyester without gel formation during the reaction, since it is not affected by the remaining catalyst even under harsh conditions such as a molten state.

After solidification, the obtained biomass polyester may be subjected to solid-phase polymerization as necessary to further increase the degree of polymerization or to remove oligomers such as cyclic trimers. Specifically, the biomass polyester is chipped and dried, then heated at a temperature of 100 to 180°C for about 1 to 8 hours to pre-crystallize the biomass polyester, and then heated at a temperature of 190 to 230°C under an inert gas flow or under reduced pressure for 1 to several tens of hours.

The intrinsic viscosity of the biomass polyester obtained as described above (measured in orthochlorophenol solution at 35°C) is preferably 0.5 dl/g to 1.5 dl/g, more preferably 0.6 dl/g to 1.2 dl/g. If the intrinsic viscosity is less than 0.5 dl/g, the mechanical properties required of the biomass polyester film as a semi-transparent reflective film substrate, including tear strength, may be insufficient. On the other hand, if the intrinsic viscosity exceeds 1.5 dl/g, productivity is impaired in the raw material production process and film formation process.

Various additives may be added during the production process of biomass polyester, or to the produced biomass polyester, as long as the properties are not impaired. For example, plasticizers, UV stabilizers, color inhibitors, matting agents, deodorants, flame retardants, weather resistance agents, antistatic agents, thread friction reducers, release agents, antioxidants, ion exchange agents, color pigments, etc. can be added. These additives are added in the range of 5 to 50% by mass, preferably 5 to 20% by mass, of the entire biomass polyester resin composition.

The polyester (hereinafter also referred to as recycled polyester), which may be contained in the biomass polyester resin composition at a ratio of 5 to 45% by mass, is a polyester obtained by recycling a product made of a polyester resin that is composed of diol units and dicarboxylic acid units and is obtained by a polycondensation reaction using a diol derived from a fossil fuel or ethylene glycol derived from biomass as the diol units and a dicarboxylic acid derived from a fossil fuel as the dicarboxylic acid units.

The resin that is the basis of recycled polyester (i.e., polyester resin before recycling) may be one in which both the diol units and the dicarboxylic acid units are made from raw materials derived from fossil fuels (non-biomass polyester), or it may be a biomass polyester as described above.

Examples of diols derived from fossil fuels that are used in the resin that is the basis of recycled polyester include aliphatic diols, aromatic diols, and derivatives thereof, and those that are used as diol units in conventional biomass polyesters can be suitably used. The aliphatic diol is not particularly limited as long as it is an aliphatic or alicyclic compound having two OH groups, but examples of the aliphatic diol include aliphatic diols having a lower limit of 2 or more and an upper limit of usually 10 or less, preferably 6 or less, of carbon atoms. Specific examples include ethylene glycol, 1,3-propylene glycol, neopentyl glycol, 1,6-hexamethylene glycol, decamethylene glycol, 1,4-butanediol, and 1,4-cyclohexanedimethanol. These may be used alone or as a mixture of two or more. Among these, ethylene glycol, 1,4-butanediol, 1,3-propylene glycol, and 1,4-cyclohexanedimethanol are preferred, and ethylene glycol is particularly preferred.

The biomass polyester resin composition containing the biomass polyester obtained as described above preferably contains 10 to 19% of biomass-derived carbon based on radiocarbon (C14) measurement relative to the total carbon in the biomass polyester. Carbon dioxide in the atmosphere contains a certain proportion of C14 (105.5 pMC), and it is known that the C14 content in plants that grow by absorbing carbon dioxide in the atmosphere, such as corn, is also about 105.5 pMC. 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 the total carbon atoms in the biomass polyester. In the present invention, the content of biomass-derived carbon P _bio when the content of C14 in the biomass polyester is P _C14 is defined as follows.
P _bio (%) = P _C14 /105.5×100

Taking polyethylene terephthalate as an example, polyethylene terephthalate is a polymer of ethylene glycol containing 2 carbon atoms and terephthalic acid containing 8 carbon atoms at a molar ratio of 1:1. Therefore, when only biomass-derived ethylene glycol is used, the content of biomass-derived carbon in the biomass polyester, P _bio , is 20%. In the present invention, the content of biomass-derived carbon measured by radioactive carbon (C14) is preferably 10 to 19% relative to the total carbon in the biomass polyester resin composition. If the biomass-derived carbon content in the biomass polyester resin composition is less than 10%, the effect as a carbon offset material is poor. On the other hand, as described above, the biomass-derived carbon content in the biomass polyester resin composition is preferably as close to 20% as possible, but due to problems in the film manufacturing process and physical properties, it is preferable to include recycled polyester and additives as described above in the resin, so the actual upper limit is 18%.

The biomass polyester resin layer is preferably a biomass polyester resin film made of the biomass polyester resin composition described above. To process the biomass polyester resin composition into a film, a method for forming a film from a conventional polyester resin can be adopted. Specifically, after drying the biomass polyester resin composition described above, it is fed to a melt extruder heated to a temperature (Tm) to Tm+70°C above the melting point of the biomass polyester to melt the biomass polyester resin composition, extruded into a sheet from a die such as a T-die, and the extruded sheet is quenched and solidified by a rotating cooling drum or the like to form a film. As the melt extruder, a single screw extruder, a twin screw extruder, a vent extruder, a tandem extruder, or the like can be used according to the purpose.

The biomass polyester resin film is preferably biaxially stretched. Biaxial stretching can be performed by a conventional method. For example, the film extruded onto the cooling drum as described above is subsequently heated by roll heating, infrared heating, or the like, and stretched in the longitudinal direction to form a longitudinally stretched film. This stretching is preferably performed by utilizing the peripheral speed difference between two or more rolls. The longitudinal stretching is usually performed in a temperature range of 50 to 100°C. The longitudinal stretching ratio is preferably 2.5 to 4.2 times, although it depends on the required properties of the film application. If the stretching ratio is less than 2.5 times, the thickness unevenness of the biomass polyester film becomes large, making it difficult to obtain a good film.

The longitudinally stretched film is then subjected to the sequential processing steps of transverse stretching, heat setting, and heat relaxation to become a biaxially stretched film. Transverse stretching is usually performed at a temperature range of 50 to 100°C. The transverse stretching ratio is preferably 2.5 to 5.0 times, depending on the required characteristics of the application. If it is less than 2.5 times, the film thickness will become uneven and it will be difficult to obtain a good film, and if it exceeds 5.0 times, breakage will occur easily during film production.

After the transverse stretching, a heat setting process is performed. The preferred temperature range for heat setting is Tg+70 to Tm-10°C of the biomass polyester. The heat setting time is preferably 1 to 60 seconds. For applications requiring a reduction in the thermal shrinkage rate, a heat relaxation process may be performed as necessary.

The thickness of the stretched film of the resin film obtained as described above is optional depending on the application, but is usually about 5 to 500 μm. The breaking strength of such a resin film is 5 to 40 kg/mm ² in the MD direction and 5 to 35 kg/mm ² in the TD direction, and the breaking elongation is 50 to 350% in the MD direction and 50 to 300% in the TD direction. In addition, the shrinkage rate when left in a temperature environment of 150° C. for 30 minutes is 0.1 to 5%. Thus, the biomass polyester resin film used as the biomass resin layer of the laminate according to the present invention has physical properties equivalent to those of polyester resin films produced only from conventional materials derived from fossil fuels.

Biomass polyolefin resin layer In the present invention, the biomass polyolefin resin layer contains ethylene derived from biomass, as described below, in an amount of preferably 5% by mass or more, more preferably 5 to 95% by mass, and even more preferably 25 to 75% by mass, based on the entire biomass polyolefin resin layer. The biomass polyolefin resin layer may be composed of at least two layers, and may, for example, have a first biomass polyolefin resin layer and a second biomass polyolefin resin layer in that order from the biomass polyester resin layer side. Both the seal layer and the core layer of the laminate may be biomass polyolefin resin layers, or only one of them may be a biomass polyolefin resin layer.

First biomass polyolefin resin layer In the present invention, the first biomass polyolefin resin layer may function as a core layer of the laminate. By having the core layer, the laminate can exhibit excellent flexibility without breaking.

The first biomass polyolefin resin layer preferably contains 5% by mass or more, more preferably 5 to 95% by mass, even more preferably 25 to 75% by mass, and most preferably 40 to 75% by mass of biomass-derived ethylene relative to the entire first biomass polyolefin resin layer. If the concentration of biomass-derived ethylene in the first biomass polyolefin resin layer is 5% by mass or more, it is possible to reduce the amount of fossil fuel used compared to conventional methods, and a carbon-neutral polyolefin resin laminate can be realized.

The first biomass polyolefin resin layer preferably has a density of 0.915 to 0.96 g/cm ³ , more preferably 0.92 to 0.955 g/cm ³ , and even more preferably 0.93 to 0.955 g/cm ³ . The density of the first biomass polyolefin resin layer is a value measured according to the method specified in the A method of JIS K7112-1980 after performing annealing as described in JIS K6760-1995. If the density of the first biomass polyolefin resin layer is 0.915 g/cm ³ or more, the rigidity of the first biomass polyolefin resin layer can be increased. In addition, if the density of the first biomass polyolefin resin layer is 0.96 g/cm ³ or less, the transparency and mechanical strength of the first biomass polyolefin resin layer can be increased.

The first biomass polyolefin resin layer has a melt flow rate (MFR) of 1 to 30 g/10 min, preferably 3 to 25 g/10 min, and more preferably 4 to 20 g/10 min. The melt flow rate is a value measured by Method A under conditions of a temperature of 190°C and a load of 21.18 N in the method specified in JIS K7210-1995. If the MFR of the first biomass polyolefin resin layer is 1 g/10 min or more, the extrusion load during molding can be reduced. Furthermore, if the MFR of the biomass polyolefin resin composition is 30 g/10 min or less, the mechanical strength of the first biomass polyolefin resin layer can be increased.

The first biomass polyolefin resin layer has a thickness of 10 to 100 μm, preferably 10 to 50 μm, and more preferably 15 to 30 μm.

Second biomass polyolefin resin layer In the present invention, the second biomass polyolefin resin layer may function as a seal layer of the laminate. By having a heat seal layer, the laminate can be firmly bonded to another resin film without using an adhesive or the like when laminated on the other resin film.

The second biomass polyolefin resin layer preferably contains 5% by mass or more, more preferably 5 to 95% by mass, and even more preferably 25 to 75% by mass of biomass-derived ethylene relative to the entire second biomass polyolefin resin layer. If the concentration of biomass-derived ethylene in the second biomass polyolefin resin layer is 5% by mass or more, the amount of fossil fuel used can be reduced compared to conventional methods, and a carbon-neutral polyolefin laminate can be realized.

The second biomass polyolefin resin layer has a density of 0.90 to 0.925 g/cm ³ , preferably 0.905 to 0.925 g/cm ³ . The density of the second biomass polyolefin resin layer is a value measured according to the method specified in Method A of JIS K7112-1980 after performing annealing as described in JIS K6760-1995. If the density of the second biomass polyolefin resin layer is 0.90 g/cm ³ or more, the rigidity of the second biomass polyolefin resin layer can be increased. In addition, if the density of the second biomass polyolefin resin layer is 0.925 g/cm ³ or less, the transparency and mechanical strength of the second biomass polyolefin resin layer can be increased.

The second biomass polyolefin resin layer has a melt flow rate (MFR) of 1 to 30 g/10 min, preferably 3 to 25 g/10 min, and more preferably 4 to 20 g/10 min. The melt flow rate is a value measured by Method A under conditions of a temperature of 190°C and a load of 21.18 N in the method specified in JIS K7210-1995. If the MFR of the second biomass polyolefin resin layer is 1 g/10 min or more, the extrusion load during molding can be reduced. Furthermore, if the MFR of the biomass polyolefin resin composition is 30 g/10 min or less, the mechanical strength of the second biomass polyolefin resin layer can be increased.

The second biomass polyolefin resin layer has a thickness of 1 to 50 μm, preferably 1 to 20 μm, and more preferably 1 to 10 μm.

In the present invention, it is preferable that the first biomass polyolefin resin layer and the second biomass polyolefin resin layer satisfy the following specific relationships with respect to density, thickness, MFR, and biomass degree (concentration of ethylene derived from biomass).

In the present invention, it is preferable that the density _d1 of the first biomass polyolefin resin layer and the density _d2 of the second biomass polyolefin resin layer satisfy _d1 > _d2 . This is because the first biomass polyolefin resin layer functions as a core layer and therefore requires rigidity, and the second biomass polyolefin resin layer functions as a heat seal layer and therefore requires flexibility.

In the present invention, it is preferable that the thickness _t1 of the first biomass polyolefin resin layer and the thickness _t2 of the second biomass polyolefin resin layer satisfy _t1 > _t2 . This is because the first biomass polyolefin resin layer functions as a core layer and therefore requires a thickness, whereas the second biomass polyolefin resin layer functions as a heat seal layer and therefore does not require as much thickness as the core layer.

In the present invention, it is preferable that MFR ₁ of the first biomass polyolefin resin layer and MFR ₂ of the second biomass polyolefin resin layer satisfy MFR ₁ > MFR _2. This is because the first biomass polyolefin resin layer functions as a core layer and therefore requires rigidity, and the second biomass polyolefin resin layer functions as a heat seal layer and therefore requires flexibility.

In the present invention, it is preferable that the biomass-derived ethylene concentration _C1 of the first biomass polyolefin resin layer and the biomass-derived ethylene concentration _C2 of the second biomass polyolefin resin layer satisfy _C1 > _C2 . Since the first biomass polyolefin resin layer functions as a core layer, it is thick and uses a large amount of ethylene, and therefore by increasing the biomass degree of the first biomass polyolefin resin layer, the amount of fossil fuel used can be further reduced.

In the present invention, the method for producing biomass-derived ethylene, which is a raw material for biomass-derived polyolefin, is not particularly limited, and can be obtained by a conventionally known method. An example of the method for producing biomass-derived ethylene is described below.

Biomass-derived ethylene can be produced using biomass-derived ethanol as a raw material. In particular, it is preferable to use biomass-derived fermented ethanol obtained from plant raw materials. There are no particular limitations on the plant raw material, and any conventionally known plant can be used. Examples include corn, sugar cane, beet, and manioc.

In the present invention, fermented ethanol derived from biomass refers to ethanol produced by contacting a culture solution containing a carbon source obtained from a plant raw material with an ethanol-producing microorganism or a product derived from its crushed material, and then purifying the ethanol. Conventionally known methods such as distillation, membrane separation, and extraction can be used to purify ethanol from the culture solution. For example, methods include adding benzene, cyclohexane, etc., and removing water by azeotropy or membrane separation, etc.

To obtain the ethylene of the present invention, further advanced purification may be carried out at this stage, such as reducing the total amount of impurities in the ethanol to 1 ppm or less.

A catalyst is usually used to obtain ethylene by the dehydration reaction of ethanol, but there is no particular limitation on the catalyst, and any conventionally known catalyst can be used. From a process standpoint, a fixed-bed flow reaction is advantageous because it is easy to separate the catalyst from the product; for example, gamma-alumina is preferred.

This dehydration reaction is an endothermic reaction, so it is usually carried out under heating conditions. There are no limitations on the heating temperature as long as the reaction proceeds at a commercially useful reaction rate, but a temperature of 100°C or higher is preferable, more preferably 250°C or higher, and even more preferably 300°C or higher is appropriate. There is no particular upper limit, but from the viewpoint of energy balance and equipment, it is preferably 500°C or lower, more preferably 400°C or lower.

The reaction pressure is not particularly limited, but a pressure equal to or higher than atmospheric pressure is preferred to facilitate the subsequent gas-liquid separation. From an industrial perspective, a fixed-bed flow reaction is preferred because it is easy to separate the catalyst, but a liquid-phase suspension bed, fluidized bed, etc. may also be used.

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. In general, when performing a dehydration reaction, it is preferable to have no water, considering the efficiency of removing water. However, in the case of the dehydration reaction of ethanol using a solid catalyst, it has been found that the amount of other olefins, especially butene, produced tends to increase if water is not present. This is probably because the presence of a small amount of water makes it difficult to suppress ethylene dimerization after dehydration. The lower limit of the allowable water content is 0.1% or more, preferably 0.5% or more. There is no particular upper limit, but from the viewpoint of material balance and heat balance, it is preferably 50% by mass or less, more preferably 30% or less, and even more preferably 20% or less.

By carrying out the dehydration reaction of ethanol in this way, a mixture of ethylene, water and a small amount of unreacted ethanol is obtained. However, since ethylene is in a gaseous state at room temperature and below about 5 MPa, water and ethanol can be removed from this mixture by gas-liquid separation to obtain ethylene. This method may be carried out by any known method.

The ethylene obtained by gas-liquid separation is further distilled, and there are no particular restrictions on the distillation method, operating temperature, residence time, etc., except that the operating pressure at this time must be normal pressure or higher.

When the raw material is biomass-derived ethanol, the obtained ethylene contains trace amounts of carbonyl compounds such as ketones, aldehydes, and esters, which are impurities mixed in during the ethanol fermentation process, as well as carbon dioxide, which is their decomposition product, and nitrogen-containing compounds such as amines and amino acids, which are enzyme decomposition products and impurities, as well as ammonia, which is their decomposition product. Depending on the use of ethylene, these trace amounts of impurities may be problematic, so they may be removed by purification. The purification method is not particularly limited, and can be performed by a conventionally known method. An example of a suitable purification operation is an adsorption purification method. The adsorbent used is not particularly limited, and conventionally known adsorbents can be used. For example, a material with a high surface area is preferable, and the type of adsorbent is selected according to the type and amount of impurities in the ethylene obtained by the dehydration reaction of biomass-derived ethanol.

Caustic water treatment may also be used in combination as a method for purifying impurities in ethylene. If caustic water treatment is used, it is preferable to carry it out before adsorption purification. In that case, it is necessary to carry out a moisture removal treatment after the caustic treatment and before adsorption purification.

Biomass polyolefin In the present invention, the biomass-derived polyolefin is obtained by polymerizing a monomer containing biomass-derived ethylene. It is preferable to use the biomass-derived ethylene obtained by the above-mentioned manufacturing method. Since biomass-derived ethylene is used as the raw material monomer, the polymerized polyolefin is derived from biomass. Note that the raw material monomer of the polyolefin does not have to contain 100% by mass of biomass-derived ethylene.

The monomers that are the raw materials for biomass-derived polyolefins may further contain ethylene and/or α-olefins derived from fossil fuels, or may further contain α-olefins derived from biomass.

The above α-olefins are not particularly limited in the number of carbon atoms, but those with 3 to 20 carbon atoms can usually be used, and butylene, hexene, or octene are preferable. This is because butylene, hexene, or octene can be produced by polymerizing ethylene, a raw material derived from biomass. In addition, by including such α-olefins, the polyolefin obtained by polymerization has alkyl groups as a branched structure, making it more flexible than simple linear ones.

The polyolefin is preferably polyethylene. This is because, by using ethylene, a raw material derived from biomass, it is theoretically possible to produce the polyolefin from 100% biomass-derived components.

The biomass-derived ethylene concentration in the polyolefin (hereinafter sometimes referred to as "biomass degree") is a value obtained by measuring the content of biomass-derived carbon by radiocarbon (C14) measurement. Carbon dioxide in the atmosphere contains a certain proportion of C14 (105.5 pMC), and it is known that the C14 content in plants that grow by absorbing carbon dioxide from the atmosphere, such as corn, is also about 105.5 pMC. 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 the total carbon atoms in the polyolefin. In the present invention, when the content of C14 in the polyolefin is P _C14 , the content of biomass-derived carbon P _bio can be calculated as follows.
P _bio (%) = P _C14 /105.5×100

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

In the present invention, the biomass-derived polyolefin and the biomass-derived resin layer do not need to have a biomass content of 100%. This is because the use of biomass-derived raw materials in even a part of the laminate is in line with the purpose of the present invention, which is to reduce the amount of fossil fuel used compared to conventional methods.

In the present invention, the polymerization method of the ethylene-containing monomer derived from biomass is not particularly limited, and can be carried out by a conventionally known method. The polymerization temperature and polymerization pressure should be appropriately adjusted depending on the polymerization method and polymerization apparatus. The polymerization apparatus is also not particularly limited, and a conventionally known apparatus can be used. An example of the polymerization method of the ethylene-containing monomer is described below.

The polymerization method for polyolefins, particularly ethylene polymers and copolymers of ethylene and α-olefins, can be appropriately selected depending on the type of polyethylene desired, for example, differences in density and branching such as high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE), and linear low density polyethylene (LLDPE). For example, it is preferable to use a multi-site catalyst such as a Ziegler-Natta catalyst or a single-site catalyst such as a metallocene catalyst as the polymerization catalyst, and carry out the polymerization in one stage or in multiple stages of two or more stages by any of the methods of gas phase polymerization, slurry polymerization, solution polymerization, and high pressure ionic polymerization.

The single-site catalyst is a catalyst capable of forming a uniform active species, and is usually prepared by contacting a metallocene transition metal compound or a nonmetallocene transition metal compound with an activating cocatalyst. Compared to multi-site catalysts, single-site catalysts have a uniform active site structure, and are therefore preferred because they can polymerize polymers with high molecular weights and highly uniform structures. As a single-site catalyst, it is particularly preferred to use a metallocene catalyst. A metallocene catalyst is a catalyst that contains each of the catalytic components of a transition metal compound of Group IV of the periodic table that contains a ligand having a cyclopentadienyl skeleton, a cocatalyst, and if necessary, an organometallic compound and a carrier.

In the above-mentioned transition metal compound of Group IV of the periodic table containing a ligand having a cyclopentadienyl skeleton, the cyclopentadienyl skeleton is a cyclopentadienyl group, a substituted cyclopentadienyl group, or the like. The substituted cyclopentadienyl group has at least one substituent selected from a hydrocarbon group having 1 to 30 carbon atoms, a silyl group, a silyl-substituted alkyl group, a silyl-substituted aryl group, a cyano group, a cyanoalkyl group, a cyanoaryl group, a halogen group, a haloalkyl group, a halosilyl group, or the like. The substituted cyclopentadienyl group may have two or more substituents, and the substituents may be bonded to each other to form a ring, such as an indenyl ring, a fluorenyl ring, an azulenyl ring, or a hydrogenated product thereof. The rings formed by bonding the substituents to each other may further have substituents.

In the transition metal compound of Group IV of the periodic table containing a ligand having a cyclopentadienyl skeleton, the transition metal may be zirconium, titanium, hafnium, etc., with zirconium and hafnium being particularly preferred. The transition metal compound usually has two ligands having a cyclopentadienyl skeleton, and it is preferred that the ligands having the cyclopentadienyl skeleton are bonded to each other via a bridging group. Examples of the bridging group include alkylene groups having 1 to 4 carbon atoms, silylene groups, substituted silylene groups such as dialkylsilylene groups and diarylsilylene groups, and substituted germylene groups such as dialkylgermylene groups and diarylgermylene groups. The substituted silylene group is preferred.

In transition metal compounds of Group IV of the periodic table, representative ligands other than those having a cyclopentadienyl skeleton include hydrogen, hydrocarbon groups having 1 to 20 carbon atoms (alkyl groups, alkenyl groups, aryl groups, alkylaryl groups, aralkyl groups, polyenyl groups, etc.), halogens, metaalkyl groups, metaaryl groups, etc.

The above-mentioned transition metal compounds of Group IV of the periodic table containing a ligand having a cyclopentadienyl skeleton can be used as a catalyst component, either alone or in a mixture of two or more kinds.

The co-catalyst refers to a catalyst that can effectively use the above-mentioned transition metal compound of Group IV of the periodic table as a polymerization catalyst, or can balance the ionic charge in a catalytically activated state. Examples of the co-catalyst include benzene-soluble aluminoxanes of organoaluminum oxy compounds and benzene-insoluble organoaluminum oxy compounds, ion-exchangeable layered silicates, boron compounds, ionic compounds consisting of cations with or without active hydrogen groups and non-coordinating anions, lanthanoid salts such as lanthanum oxide, tin oxide, and phenoxy compounds containing fluoro groups.

The transition metal compound of Group IV of the periodic table containing a ligand having a cyclopentadienyl skeleton may be used supported on an inorganic or organic carrier, preferably an inorganic or organic porous oxide, specifically _{montmorillonite or other ion-exchangeable layered silicate, SiO2, Al2O3 , MgO , ZrO2} , _TiO2 , _B2O3 , CaO, ZnO, BaO, _ThO2 , or mixtures thereof.

Furthermore, examples of organometallic compounds that may be used as necessary include organoaluminum compounds, organomagnesium compounds, and organozinc compounds. Of these, organoaluminum compounds are preferably used.

As the polyolefin, ethylene polymers and copolymers of ethylene and α-olefins may be used alone or in combination of two or more kinds.

Biomass polyolefin resin composition In the present invention, the biomass polyolefin resin composition contains the above-mentioned polyolefin as a main component. The biomass polyolefin resin composition contains ethylene derived from biomass in an amount of preferably 5% by mass or more, more preferably 5 to 95% by mass, and even more preferably 25 to 75% by mass, based on the entire biomass polyolefin resin composition. If the concentration of biomass-derived ethylene in the biomass polyolefin resin composition is 5% by mass or more, the amount of fossil fuel used can be reduced compared to conventional methods, and a carbon-neutral polyolefin laminate can be realized.

The biomass polyolefin resin composition may contain two or more polyolefins with different biomass degrees, and the concentration of biomass-derived ethylene in the biomass polyolefin resin composition as a whole may be within the above range.

The biomass polyolefin resin composition may further contain a fossil fuel-derived polyolefin obtained by polymerizing a monomer containing fossil fuel-derived ethylene and fossil fuel-derived ethylene and/or α-olefin. In other words, in the present invention, the biomass polyolefin resin composition may be a mixture of a biomass-derived polyolefin and a fossil fuel-derived polyolefin. The mixing method is not particularly limited, and mixing can be performed by a conventionally known method. For example, dry blending or melt blending may be used.

According to an embodiment of the present invention, the biomass polyolefin resin composition contains preferably 5 to 90 mass%, more preferably 25 to 75 mass%, of biomass-derived polyolefin, and preferably 10 to 95 mass%, more preferably 25 to 75 mass%, of fossil fuel-derived polyolefin. Even when a biomass polyolefin resin composition containing such a mixture is used, it is sufficient that the concentration of biomass-derived ethylene in the biomass polyolefin resin composition as a whole is within the above range.

In the manufacturing process of the biomass polyolefin resin composition described above, or to the manufactured biomass polyolefin resin composition, various additives may be added in addition to the main component polyolefin, as long as the properties of the composition are not impaired. Examples of additives that can be added include plasticizers, UV stabilizers, color inhibitors, matting agents, deodorants, flame retardants, weather resistance agents, antistatic agents, thread friction reducers, slip agents, mold release agents, antioxidants, ion exchange agents, and color pigments. These additives are preferably added in an amount of 1 to 20% by mass, and more preferably 1 to 10% by mass, based on the total biomass polyolefin resin composition.

Non-biomass polyolefin resin layer The laminate according to the present invention may further have a non-biomass polyolefin resin layer. The non-biomass polyolefin resin layer is a resin layer made of a resin material containing a raw material derived from a fossil fuel, and has a biomass degree of 0%. When only one of the core layer and the seal layer of the laminate is a biomass polyolefin resin layer, the other may be a non-biomass polyolefin resin layer. The non-biomass polyolefin resin layer can be formed using a conventionally known raw material, and its composition and formation method are not particularly limited. By further having a non-biomass polyolefin resin layer, the laminate can impart or improve heat resistance, pressure resistance, water resistance, heat sealability, pinhole resistance, puncture resistance, and other physical properties. The laminate may have two or more non-biomass polyolefin resin layers. When the laminate has two or more non-biomass polyolefin resin layers, each may have the same composition or different compositions.

For example, resins such as low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, polypropylene, propylene-ethylene copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl methacrylate copolymer, or ionomer can be used as the non-biomass polyolefin resin layer. These resins may be formed by extrusion lamination, or may be formed into a film by the T-die method or inflation method, etc., and laminated to the heat-resistant substrate layer by dry lamination or extrusion lamination, etc.

It may also be any of stretched polyethylene terephthalate film, silica-deposited stretched polyethylene terephthalate film, alumina-deposited stretched polyethylene terephthalate film, stretched nylon film, silica-deposited stretched nylon film, alumina-deposited stretched nylon film, stretched polypropylene film, polyvinyl alcohol-coated stretched polypropylene film, nylon 6/metaxylylenediamine nylon 6 co-extruded co-stretched film, and polypropylene/ethylene-vinyl alcohol copolymer co-extruded co-stretched film, or a composite film made by laminating two or more of these films.

Barrier layer The laminate according to the present invention may further have a barrier layer. The barrier layer is made of an inorganic substance and/or an inorganic oxide, and is preferably made of a vapor-deposited film of an inorganic substance or an inorganic oxide or a metal foil. The vapor-deposited film can be formed by a conventionally known method using a conventionally known inorganic substance or inorganic oxide, and its composition and forming method are not particularly limited. When the laminate further has a barrier layer, it can impart or improve gas barrier properties that prevent the transmission of oxygen gas, water vapor, etc., and light-shielding properties that prevent the transmission of visible light, ultraviolet rays, etc. The laminate may have two or more barrier layers. When the laminate has two or more barrier layers, each layer may have the same composition or different compositions.

Examples of the deposited film that can be used include deposited films of inorganic substances or inorganic oxides such as silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B), titanium (Ti), lead (Pb), zirconium (Zr), and yttrium (Y). In particular, a deposited film of aluminum metal, or a deposited film of silicon oxide, aluminum metal, or aluminum oxide is suitable for use in packaging materials (bags) and the like.

Inorganic oxides are expressed as _MOx (wherein M represents an inorganic element, and the value of X varies depending on the inorganic element), such as _SiOx , _AlOx , etc. The range of the value of X is as follows: silicon (Si) is 0-2, aluminum (Al) is 0-1.5, magnesium (Mg) is 0-1, calcium (Ca) is 0-1, potassium (K) is 0-0.5, tin (Sn) is 0-2, sodium (Na) is 0-0.5, boron (B) is 0-1.5, titanium (Ti) is 0-2, lead (Pb) is 0-1, zirconium (Zr) is 0-2, and yttrium (Y) is 0-1.5. In the above, when X=0, it is a completely inorganic element (pure substance) and is not transparent, and the upper limit of the range of X is the value when it is completely oxidized. Silicon (Si) and aluminum (Al) are preferably used for the packaging material, and silicon (Si) with a value in the range of 1.0 to 2.0 and aluminum (Al) with a value in the range of 0.5 to 1.5 can be used.

In the present invention, the thickness of the vapor-deposited film of the inorganic substance or inorganic oxide as described above varies depending on the type of inorganic substance or inorganic oxide used, but it is desirable to select and form the film at any thickness within the range of, for example, about 50 to 2000 Å, preferably about 100 to 1000 Å. More specifically, in the case of a vapor-deposited film of aluminum, the thickness is preferably about 50 to 600 Å, more preferably about 100 to 450 Å, and in the case of a vapor-deposited film of aluminum oxide or silicon oxide, the thickness is preferably about 50 to 500 Å, more preferably about 100 to 300 Å.

Methods for forming the vapor-deposited film include, for example, physical vapor deposition methods (PVD methods) such as vacuum deposition, sputtering, and ion plating, or chemical vapor deposition methods (CVD methods) such as plasma chemical vapor deposition, thermal chemical vapor deposition, and photochemical vapor deposition.

In another embodiment, the barrier layer may be a metal foil obtained by rolling a metal. Any conventional metal foil may be used as the metal foil. Aluminum foil is preferred from the viewpoints of gas barrier properties that prevent the transmission of oxygen gas, water vapor, etc., and light blocking properties that prevent the transmission of visible light, ultraviolet light, etc.

Paper Layer The laminate according to the present invention may further have a paper layer. By having the laminate have a paper layer, it is possible to provide the rigidity required for a container. The paper used as the paper layer has a basis weight of preferably 10 to 150 g/m ² , more preferably 20 to 100 g/m ² . The paper layer may be any "wrapping paper" of "western paper", but from the viewpoint of safety, it is preferable to use high-quality paper, art paper, etc. using 100% chemical pulp. In addition, by having a paper layer derived from biomass such as natural pulp, it is possible to improve the biomass degree of the entire laminate, and it is also possible to realize an all-biomass laminate.

Other layers The laminate according to the present invention may further have at least one other layer in addition to the above-mentioned layers. When the laminate has two or more other layers, each of them may have the same composition or different compositions. The other layers can be formed on any one or more of the above-mentioned layers. Examples of the other layers include a printed layer and an adhesive layer. The printed layer can be formed using a conventionally known pigment or dye, and the method of forming the printed layer is not particularly limited. The adhesive layer is an adhesive layer or an adhesive resin layer formed to bond any two layers by lamination. As the lamination adhesive, for example, one-liquid or two-liquid type cured or non-cured vinyl, (meth)acrylic, polyamide, polyester, polyether, polyurethane, epoxy, rubber, and other solvent-based, water-based, or emulsion-based lamination adhesives can be used. As the coating method of the above adhesive, for example, the direct gravure roll coating method, gravure roll coating method, kiss coating method, reverse roll coating method, Fountain method, transfer roll coating method, and other methods can be used. The coating amount is preferably about 0.1 g/m ² to 10 g/m ² (dry state), and more preferably about 1 g/m ² to 5 g/m ² (dry state).

In addition, a resin layer made of a thermoplastic resin layer is used as the adhesive resin layer. Specifically, the adhesive resin layer may be made of low-density polyethylene resin, medium-density polyethylene resin, high-density polyethylene resin, linear low-density polyethylene resin, copolymer resin of ethylene and α-olefin polymerized using a metallocene catalyst, ethylene-polypropylene copolymer resin, ethylene-vinyl acetate copolymer resin, ethylene-acrylic acid copolymer resin, ethylene-ethyl acrylate copolymer resin, ethylene-methacrylic acid copolymer resin, ethylene-methyl methacrylate copolymer resin, ethylene-maleic acid copolymer resin, ionomer resin, resin obtained by graft-polymerizing or copolymerizing unsaturated carboxylic acid, unsaturated carboxylic acid anhydride, or ester monomer with polyolefin resin, resin obtained by graft-modifying maleic anhydride with polyolefin resin, etc. These materials may be used in combination of one or more kinds.

The method for producing the laminate according to the present invention is not particularly limited, and it can be produced by a conventionally known method. In the present invention, it is preferable to form a biomass polyolefin resin layer on a biomass polyester resin layer by extrusion molding, and it is more preferable that the biomass polyolefin resin layer is formed by coextrusion molding. It is even more preferable that the coextrusion molding is performed by a T-die method or an inflation method.

For example, a laminate can be formed by extrusion molding in the following manner. After drying the biomass polyolefin resin composition described above, it is fed to a melt extruder heated to a temperature above the melting point of the polyolefin (Tm) to Tm+70°C to melt the biomass polyolefin resin composition, and extruded onto the biomass polyester resin layer in the form of a sheet from a die such as a T-die. The extruded sheet is rapidly cooled and solidified on a rotating cooling drum or the like to form a laminate. As the melt extruder, a single screw extruder, twin screw extruder, vent extruder, tandem extruder, etc. can be used depending on the purpose.

The thickness of the laminate obtained as described above can vary depending on the application, but is usually about 5 to 500 μm, preferably about 20 to 300 μm.

The laminate of the present invention can be subjected to secondary processing in order to impart surface functions such as chemical functions, electrical functions, magnetic functions, mechanical functions, friction/wear/lubrication functions, optical functions, thermal functions, and biocompatibility. Examples of secondary processing include embossing, painting, adhesion, printing, metallizing (plating, etc.), machining, and surface treatment (antistatic treatment, corona discharge treatment, plasma treatment, photochromism treatment, physical vapor deposition, chemical vapor deposition, coating, etc.). The laminate of the present invention can also be subjected to lamination (dry lamination and extrusion lamination), bag making, and other post-treatment processes to manufacture molded products.

The laminate according to the present invention can be suitably used for various applications, including packaging products such as packaging containers and packaging bags, sheet molded products such as decorative sheets and trays, laminated films, optical films, resin plates, various label materials, lid materials, and laminate tubes, and is particularly preferred for packaging products.

Another aspect of the present invention is to provide a laminate having a biomass polyester resin layer containing a carbon-neutral polyester using ethylene glycol derived from biomass, and a biomass polyolefin resin layer containing a carbon-neutral polyolefin using ethylene derived from biomass. It is also an object of the present invention to provide a biomass resin laminate that is comparable in physical properties, such as mechanical properties, to a laminate having a polyester resin layer and a polyolefin resin layer produced from raw materials obtained from conventional fossil fuels.
According to yet another aspect of the present invention,
A biomass polyester resin layer made of a biomass polyester resin composition containing a polyester composed of a diol unit and a dicarboxylic acid unit as a main component, the diol unit being ethylene glycol derived from biomass;
and a biomass polyolefin resin layer made of a biomass polyolefin resin composition containing a biomass-derived polyolefin obtained by polymerizing a monomer containing ethylene derived from biomass.
In an aspect of the present invention, the biomass polyolefin resin layer may contain 5 mass % or more of ethylene derived from the biomass based on the entirety of the biomass polyolefin resin layer.
In an embodiment of the present invention, the biomass polyolefin resin layer has, in order from the biomass polyester resin layer side, a first biomass polyolefin resin layer and a second biomass polyolefin resin layer, the first biomass polyolefin resin layer contains 5% by mass or more of ethylene derived from the biomass based on the entire first biomass polyolefin resin layer, and the second biomass polyolefin resin layer contains 5% by mass or more of ethylene derived from the biomass based on the entire second biomass polyolefin resin layer.
In an embodiment of the present invention, the concentration _C1 of biomass-derived ethylene in the first biomass polyolefin resin layer and the concentration _C2 of biomass-derived ethylene in the second biomass polyolefin resin layer may satisfy _C1 > _C2 .
In an embodiment of the invention, the monomers may further comprise ethylene and/or alpha-olefins derived from fossil fuels.
In an embodiment of the present invention, the monomer may further comprise an α-olefin derived from biomass.
In an embodiment of the present invention, the biomass polyolefin resin composition may further contain a fossil fuel-derived polyolefin obtained by polymerizing a monomer containing ethylene derived from a fossil fuel and ethylene and/or an α-olefin derived from a fossil fuel.
In an aspect of the present invention, the biomass polyolefin resin composition may contain 5 to 90% by mass of the biomass-derived polyolefin and 10 to 95% by mass of the fossil fuel-derived polyolefin.
In an embodiment of the present invention, the α-olefin may be butylene, hexene, or octene.
In an embodiment of the present invention, the polyolefin may be polyethylene.
In an aspect of the present invention, the laminate may further include a non-biomass polyolefin resin layer made of a resin material containing a raw material derived from a fossil fuel.
In an aspect of the present invention, the laminate may further include a barrier layer made of an inorganic material and/or an inorganic oxide.
In an aspect of the present invention, the laminate may further include a paper layer.
In an aspect of the present invention, the biomass polyolefin resin layer may be formed on the biomass polyester resin layer by extrusion molding.
In an aspect of the present invention, the biomass polyolefin resin layer may be formed by coextrusion molding.
In an embodiment of the present invention, the co-extrusion molding may be carried out by a T-die method or an inflation method.
In another aspect of the present invention, there is provided a packaging product comprising the laminate described above.
The laminate according to the present invention has a biomass polyester resin layer containing a carbon-neutral polyester using ethylene glycol derived from biomass, and a biomass polyolefin resin layer containing a carbon-neutral polyolefin using ethylene derived from biomass, thereby realizing a carbon-neutral biomass resin laminate. Therefore, the amount of fossil fuel used can be significantly reduced compared to the conventional method, and the environmental load can be reduced. In addition, the laminate according to the present invention is comparable in physical properties such as mechanical properties to conventional resin laminates manufactured from raw materials obtained from fossil fuels, and can therefore replace conventional resin laminates.

The present invention will be explained in more detail below with reference to examples and comparative examples, but the present invention should not be construed as being limited to the following examples.

Measurement Conditions In the following Reference Examples, Reference Comparative Examples, Examples, and Comparative Examples, the biomass degree refers to the content of carbon derived from biomass as determined by radiocarbon (C14) measurement.

The conditions of the extrusion film-forming machine used below were as follows.
Screw diameter: 90mm
Screw type: Full flight L/D: 28
T-die: 11S type straight manifold T-die effective opening length: 560 mm

Preparation of resin film for core layer
Reference Example 1
A biomass-derived high-density polyethylene (manufactured by Braskem, product name: SHA7260, biomass ratio: 94.5%, density: 0.955 g/cm ³ , MFR: 20 g/10 min) was extruded onto a 12 μm-thick PET film (manufactured by Toyobo, product name: E5100) at a resin temperature of 290° C. to obtain a resin film. The extrusion molding conditions were set to an effective width of 560 mm, an extrusion thickness of 30 μm, and an extrusion speed of 100 m/min.

Reference Example 2
A resin (biomass degree: 48%, density: 0.937 g/cm ³ , MFR: 17 g/10 min) obtained by dry blending 50 parts by mass of biomass-derived high density polyethylene (manufactured by Braskem, product name: SHA7260, biomass degree: 94.5%, density: 0.955 g/cm ³ , MFR: 20 g/10 min) and 50 parts by mass of fossil fuel-derived low density polyethylene (manufactured by Japan Polyethylene Co., Ltd., product name: LC701, biomass degree: 0%, density: 0.919 g/cm ³ , MFR: 14 g/10 min) was extruded onto a 12 μm-thick PET film (manufactured by Toyobo Co., Ltd., product name: E5100) at a resin temperature of 290° C. to obtain a resin film. The extrusion molding conditions were set to an effective width of 560 mm, an extrusion thickness of 30 μm, and an extrusion speed of 100 m/min.

Reference Example 3
A resin (biomass degree: 32%, density: 0.931 g/cm ³ , MFR: 16 g/10 min) obtained by dry blending 33 parts by mass of biomass-derived high density polyethylene (manufactured by Braskem, product name: SHA7260, biomass degree: 94.5%, density: 0.955 g/cm ³ , MFR: 20 g/10 min) and 67 parts by mass of fossil fuel-derived low density polyethylene (manufactured by Japan Polyethylene Co., Ltd., product name: LC701, biomass degree: 0%, density: 0.919 g/cm ³ , MFR: 14 g/10 min) was extruded onto a 12 μm-thick PET film (manufactured by Toyobo Co., Ltd., product name: E5100) at a resin temperature of 290° C. to obtain a resin film. The extrusion molding conditions were set to an effective width of 560 mm, an extrusion thickness of 30 μm, and an extrusion speed of 100 m/min.

Reference Comparative Example 1
A resin film was obtained by extruding a fossil fuel-derived low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd., product name: LC701, biomass ratio: 0%, density: 0.919 g/cm ³ , MFR: 14 g/10 min) onto a 12 μm-thick PET film (manufactured by Toyobo Co., Ltd., product name: E5100) at a resin temperature of 290° C. The extrusion molding conditions were set as follows: effective width: 560 mm, extrusion thickness: 30 μm, and extrusion speed: 100 m/min.

Evaluation of Biomass Polyolefin Resin Composition and Resin Film The processability of the biomass polyolefin resin compositions used in Reference Examples 1 to 3 and Reference Comparative Example 1 and the properties of the films obtained were evaluated in the following manner: (1) drawdown, (2) neck-in, (3) motor load, (4) resin pressure, and (5) loop stiffness.
(1) Drawdown
The biomass polyolefin resin compositions used in the above Reference Examples 1 to 3 and Reference Comparative Example 1 were subjected to measurement of the maximum take-up speed (m/min) at which the extrusion coating film broke or surged under the conditions of a T-die width of 560 mm, a resin temperature of 290° C., and a screw rotation speed of 34 rpm using the above extrusion film-forming machine. The measurement results are shown in Table 1 below.

(2) Neck-in The biomass polyolefin resin compositions used in the above Reference Examples 1 to 3 and Reference Comparative Example 1 were subjected to measurement of both ear neck-in (mm) using the above extrusion film-forming machine under conditions of a T-die width of 560 mm, a screw rotation speed of 105 rpm, a take-up speed of 140 m/min, and an air gap of 120 mm. The measurement results are shown in Table 1 below.

(3) Motor Load In the above-mentioned Reference Examples 1 to 3 and Reference Comparative Example 1, the motor load (A) was measured when the resin film was produced using the above-mentioned extrusion film-forming machine. The measurement results are shown in Table 1 below.

(4) Resin Pressure In the above-mentioned Reference Examples 1 to 3 and Reference Comparative Example 1, the resin pressure (MPa) was measured when the resin film was produced using the above-mentioned extrusion film-forming machine. The measurement results are shown in Table 1 below.

(5) Loop Stiffness The resin films obtained in the above Reference Examples 1 to 3 and Reference Comparative Example 1 were cut into pieces having a width of 15 mm and a length of 150 mm, and the stiffness (N) of the films was measured using a stiffness tester (manufactured by Toyo Seiki Seisakusho, product name: Loop Stiffness Tester). The length of the loop was 60 mm. The measurement results were as shown in Table 1 below.

Preparation of resin film for sealing layer
Reference Example 4
A biomass-derived linear low-density polyethylene (Braskeem, product name: SLL318, biomass ratio: 87%, density: 0.918 g/cm ³ , MFR: 2.7 g/10 min) was extruded onto a 12 μm-thick PET film (Toyobo, product name: E5100) at a resin temperature of 320° C. to obtain a resin film. The extrusion molding conditions were set to an effective width of 560 mm, an extrusion thickness of 30 μm, and an extrusion speed of 100 m/min.

Reference Example 5
A resin film was obtained by melt blending 33 parts by mass of biomass-derived linear low-density polyethylene (SLL318, manufactured by Braskem; biomass ratio: 87%, density: 0.918 g/cm ³ , MFR: 2.7 g/10 min) and 67 parts by mass of fossil fuel-derived low-density polyethylene (product name: LC604, manufactured by Japan Polyethylene Co., Ltd.; biomass ratio: 0%, density: 0.918 g/cm ³ , MFR: 8 g/10 min) onto a 12 μm-thick PET film (product name: E5100, manufactured by Toyobo Co. ^, Ltd.) at a resin temperature of 320° C. The extrusion conditions were set as follows: effective width: 560 mm, extrusion thickness: 30 μm, extrusion speed: 100 m/min.

Reference Example 6
A resin (biomass degree: 29%, density: 0.916 g/cm ³ , MFR: 15 g/10 min) was melt-blended with 33 parts by mass of biomass-derived linear low-density polyethylene (manufactured by Braskem, product name: SLL318, biomass degree: 87%, density: 0.918 g/cm ³ , MFR: 2.7 g/10 min), 37 parts by mass of fossil fuel-derived low-density polyethylene (manufactured by Japan Polyethylene, product name: LC604, biomass degree: 0%, density: 0.918 g/cm ^{3 , MFR: 8 g/10 min), and 30 parts by mass of fossil fuel-derived linear low-density polyethylene (manufactured by Japan Polyethylene, product name: KC573, biomass degree: 0%, density: 0.910 g/cm 3} , MFR: 15 g/10 min) ^. A resin film was obtained by extruding a 12 μm-thick PET film (manufactured by Toyobo Co., Ltd., product name: E5100) at a resin temperature of 320° C. The conditions for extrusion molding were set to an effective width of 560 mm, an extrusion thickness of 30 μm, and an extrusion speed of 100 m/min.

Reference Example 7
A resin (biomass degree: 29%, density: 0.912 g/cm ³ , MFR: 16 g/10 min) was melt-blended with 33 parts by mass of biomass-derived linear low-density polyethylene (manufactured by Braskem, product name: SLL318, biomass degree: 87%, density: 0.918 g/cm ³ , MFR: 2.7 g/10 min), 37 parts by mass of fossil fuel-derived low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd., product name: LC604, biomass degree: 0%, density: 0.918 g/cm ^{3 , MFR: 8 g/10 min), and 30 parts by mass of fossil fuel-derived linear low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd., product name: KS560T, biomass degree: 0%, density: 0.898 g/cm 3} , MFR: 16 g/10 min ⁾ . A resin film was obtained by extruding a 12 μm-thick PET film (manufactured by Toyobo Co., Ltd., product name: E5100) at a resin temperature of 320° C. The conditions for extrusion molding were set to an effective width of 560 mm, an extrusion thickness of 30 μm, and an extrusion speed of 100 m/min.

Reference Comparative Example 2
A resin film was obtained by extruding a fossil fuel-derived low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd., product name: LC600A, biomass ratio: 0%, density: 0.919 g/cm ³ , MFR: 7 g/10 min) onto a 12 μm-thick PET film (manufactured by Toyobo Co., Ltd., product name: E5100) at a resin temperature of 320° C. The extrusion molding conditions were set to an effective width of 560 mm, an extrusion thickness of 30 μm, and an extrusion speed of 100 m/min.

Evaluation of Biomass Polyolefin Resin Composition and Resin Film The processability of the biomass polyolefin resin compositions used in Reference Examples 4 to 7 and Reference Comparative Example 2 and the properties of the films obtained were evaluated in the following various ways: (6) drawdown, (7) neck-in, (8) motor load, (9) resin pressure, and (10) seal start temperature.

(6) Drawdown The biomass polyolefin resin compositions used in the above Reference Examples 4 to 7 and Reference Comparative Example 2 were subjected to the above extrusion film-forming machine under the conditions of a T-die width of 560 mm, a resin temperature of 290° C., and a screw rotation speed of 34 rpm, and the maximum take-up speed (m/min) at which the extrusion coating film broke or surged was measured. The measurement results are shown in Table 2 below.

(7) Neck-in The biomass polyolefin resin compositions used in the above Reference Examples 4 to 7 and Reference Comparative Example 2 were subjected to measurement of both ear neck-in (mm) using the above extrusion film-forming machine under conditions of a T-die width of 560 mm, a screw rotation speed of 105 rpm, a take-up speed of 140 m/min, and an air gap of 120 mm. The measurement results are shown in Table 2 below.

(8) Motor Load In the above-mentioned Reference Examples 4 to 7 and Reference Comparative Example 2, the motor load (A) was measured when the resin film was produced using the above-mentioned extrusion film-forming machine. The measurement results are shown in Table 2 below.

(9) Resin Pressure In the above-mentioned Reference Examples 4 to 7 and Reference Comparative Example 2, the resin pressure (MPa) was measured when the resin film was produced using the above-mentioned extrusion film-forming machine. The measurement results are shown in Table 2 below.

(10) Sealing initiation temperature The resin films obtained in the above Reference Examples 4 to 7 and Reference Comparative Example 2 were cut into a thickness width of 15 mm and length of 200 mm, and heat sealed at a sealing temperature of 90 to 150° C., a sealing pressure of 30 N/cm ² , and a sealing time of 1 second. The test pieces were subjected to measurement of T-time peel strength at a tensile speed of 300 mm/min using a tensile tester (Tensilon RTC-125A, manufactured by Orientec Co., Ltd.), and the temperature (° C.) at which sealing started was identified. The measurement results were as shown in Table 2 below.

Example 1
A resin was prepared by dry blending fossil fuel-derived low-density polyethylene (Japan Polyethylene Corporation: LC701, MFR: 14, density: 0.919) and biomass-derived high-density polyethylene (Braskem: SHA7260, MFR: 20, density: 0.955, biomass ratio: 94.5%) in a ratio of 50:50. This resin was extrusion coated onto paper (pure white, basis weight: 30 g/ ^m2 ) to a thickness of 15 μm, and then laminated with a biomass PET film (12 μm, biomass ratio: 14%).

Next, a resin was prepared by dry blending fossil fuel-derived low-density polyethylene (Japan Polyethylene Corporation: LC701, MFR: 14, density: 0.919) and biomass-derived high-density polyethylene (Braskem: SHA7260, MFR: 20, density: 0.955, biomass degree: 94.5%) at a ratio of 50:50 as the inner core layer of the biomass PET film (12 μm, biomass degree: 14%). In addition, a resin was prepared by melt blending fossil fuel-derived linear low-density polyethylene (Japan Polyethylene Corporation: KC581, MFR: 11, density: 0.919) and biomass-derived linear low-density polyethylene (Braskem: SLL318, MFR: 2.7, density: 0.918, biomass degree: 87%) at a ratio of 67:33 as the sealing layer. The above resins were extrusion coated on the inside of the biomass PET film via an anchor coating agent at resin temperatures of 290°C and 320°C (core layer: 15 μm, seal layer: 5 μm) to obtain a laminate. The biomass content of the extrusion layer was 44%. This laminate was used to create a pillow bag with outer dimensions of 20 mm x 100 mm and a back seal width of 5 mm.

Comparative Example 1
Paper (pure white, basis weight 30 g/m ² ) was extrusion coated with fossil fuel-derived low-density polyethylene (Japan Polyethylene Corporation: LC701, MFR: 14, density: 0.919) to a thickness of 15 μm, and then laminated with a biomass PET film (12 μm, biomass content: 14%).

Next, a fossil fuel-derived low-density polyethylene (Japan Polyethylene Corporation: LC701, MFR: 14, density: 0.919) was prepared as the inner core layer of the biomass PET film (12 μm, biomass degree: 14%). A fossil fuel-derived linear low-density polyethylene (Japan Polyethylene Corporation: KC581, MFR: 11, density: 0.919) was prepared as the sealing layer. The above resins were extrusion-coated on the inside of the biomass PET film via an anchor coating agent at resin temperatures of 290°C and 320°C (core layer: 15 μm, sealing layer: 5 μm) to obtain a laminate. The biomass degree of the extrusion layer was 0%. Using this laminate, a pillow bag with outer dimensions of 20 mm x 100 mm and a back seal width of 5 mm was created.

Each laminate obtained in Example 1 and Comparative Example 1 was cut into a width of 15 mm and a length of 200 mm, and heat sealed at a sealing temperature of 110 to 180° C., a sealing pressure of 30 N/cm ² , and a sealing time of 1 second. The test pieces were subjected to measurement of T-time peel strength at a tensile speed of 300 mm/min using a tensile tester (Tensilon RTC-125A, manufactured by Orientec Co., Ltd.), and the temperature at which sealing began was identified. The measurement results were as shown in Table 3 below.

Example 2
A resin obtained by dry-blending 50 parts by mass of fossil fuel-derived low-density polyethylene (manufactured by Japan Polyethylene Corporation: LC701, MFR: 14, density: 0.919) and 50 parts by mass of biomass-derived linear low-density polyethylene (manufactured by Braskem: SLL318, MFR: 2.7, density: 0.918, biomass degree: 87%) on a biomass-derived PET film (thickness 12 μm, biomass degree: 14%) was extruded (15 μm) through an anchor coat at a resin temperature of 300° C. and laminated with aluminum foil (manufactured by Nippon Foil Corporation: 1N30 material, thickness 7 μm). Furthermore, a resin obtained by dry blending 50 parts by mass of fossil fuel-derived low-density polyethylene (manufactured by Japan Polyethylene Corporation: LC701, MFR: 14, density: 0.919) and 50 parts by mass of biomass-derived linear low-density polyethylene (manufactured by Braskem: SLL318, MFR: 2.7, density: 0.918, biomass degree: 87%) was extruded (30 μm) onto the aluminum foil through an anchor coat at a resin temperature of 300° C. by extrusion lamination to obtain a laminate.

Comparative Example 2
A fossil fuel-derived low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd.: LC701, MFR: 14, density: 0.919) was extruded (15 μm) through an anchor coat at a resin temperature of 300 ° C. onto a biomass-derived PET film (thickness 12 μm, biomass degree: 14%), and laminated with an aluminum foil (manufactured by Japan Foil Co., Ltd.: 1N30 material, thickness 7 μm). Further, a fossil fuel-derived low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd.: LC701, MFR: 14, density: 0.919) was extruded (30 μm) through an anchor coat onto the aluminum foil at a resin temperature of 300 ° C. by extrusion lamination to obtain a laminate.

Each laminate obtained in Example 2 and Comparative Example 2 was cut into a test piece with a width of 15 mm and a length of 200 mm. The PET film and the aluminum foil were peeled away from each other, and the peel strength at time T was measured using a tensile tester (Tensilon RTC-125A, manufactured by Orientec Co., Ltd.). The tensile speed in this measurement was 50 mm/min. The measurement results are shown in Table 4 below.

The seal strength of each of the laminates obtained in Example 2 and Comparative Example 2 was measured under the same conditions as above, except that the test conditions were a sealing pressure of 30 N/ ^cm2 , a sealing time of 1 second, a sealing temperature of 170°C, and a pulling speed of 300 mm/min. The measurement results are shown in the table below.

Example 3
For use as the inner film of a long-term storage type paper container for liquid, an aluminum foil (Toyo Aluminum Co., Ltd., 7 μm) and a 12 μm-thick biomass-derived PET film (Toyobo Co., Ltd.: DE024, 12 μm) were bonded together using a dry laminate (DIC: base agent LX-703A/curing agent KR-90). Thereafter, the PET film side was coated with a polyester polyol/isocyanate two-component curing anchor agent, and a resin obtained by dry-blending 50 parts by mass of fossil fuel-derived low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd.: LC520 (MFR: 3.6, density: 0.923)) and 50 parts by mass of biomass-derived linear low-density polyethylene (manufactured by Braskem Co., Ltd.: SLL318, MFR: 2.7, density: 0.918, biomass degree: 87%) was extruded (20 μm, line speed 100 m/min) at a resin temperature of 320° C., while bonding it to a low-density polyethylene film (manufactured by Dai Nippon Printing Co., Ltd.: SKL, density: 0.923, 40 μm) to obtain a laminate. The biomass degree of the entire laminate was 10%.

Comparative Example 3
For use as the inner film of a long-term storage type paper container for liquid, an aluminum foil (Toyo Aluminum, 7 μm) and a fossil fuel-derived PET film (Toyobo: E5100, 12 μm) were bonded together using a dry laminate (DIC: base agent LX-703A/hardener KR-90). Thereafter, the PET film side was coated with a polyester polyol/isocyanate two-component curing anchor agent, and a resin obtained by dry-blending 50 parts by mass of fossil fuel-derived low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd.: LC520 (MFR: 3.6, density: 0.923)) and 50 parts by mass of biomass-derived linear low-density polyethylene (manufactured by Braskem Co., Ltd.: SLL318, MFR: 2.7, density: 0.918, biomass degree: 87%) was extruded (20 μm, line speed 100 m/min) at a resin temperature of 320° C., while bonding with a low-density polyethylene film (manufactured by Dai Nippon Printing Co., Ltd.: SKL, density: 0.923, 40 μm) to obtain a laminate. The biomass degree of the entire laminate was 7%.

REFERENCE SIGNS LIST 10 Laminate 11 Biomass polyester resin layer 12 Biomass polyolefin resin layer 20 Laminate 21 Biomass polyester resin layer 22 First biomass polyolefin resin layer 23 Second biomass polyolefin resin layer

Claims (5)

a fossil fuel polyester resin layer made of a fossil fuel polyester resin composition containing, as a main component, a polyester composed of a fossil fuel-derived diol unit and a fossil fuel-derived dicarboxylic acid unit;
A barrier layer including an inorganic material;
A biomass polyolefin resin layer made of a biomass polyolefin resin composition containing biomass-derived polyethylene obtained by polymerizing a monomer containing ethylene derived from biomass;
A non-biomass polyolefin resin layer made of a resin material containing a raw material derived from a fossil fuel;
and
It has two or more non-biomass polyolefin resin layers, including the above-mentioned ones,
A laminate for packaging products, wherein the resin constituting at least one of the non-biomass polyolefin resin layers is polypropylene. The laminate for packaging products according to claim 1, wherein the barrier layer comprises a vapor-deposited film of an inorganic substance or an inorganic oxide. The laminate for packaging products according to claim 1 or 2, wherein the biomass polyolefin resin layer comprises biomass-derived low-density polyethylene and/or biomass-derived linear low-density polyethylene. The laminate for packaging products according to any one of claims 1 to 3, wherein the biomass polyolefin resin layer contains 5% by mass or more of ethylene derived from the biomass relative to the entire biomass polyolefin resin layer. A packaging product comprising the laminate for packaging products according to any one of claims 1 to 4.