JP6379479B2 - Polyester film - Google Patents

Description

  The present invention relates to a polyester film, and more particularly to a polyester film using a biomass-derived polyester resin and a recycled polyester resin recovered from a packaging material or the like so that it can be used again as a raw material of the film.

  Plastics, which are materials derived from fossil fuels, are mainly used in the manufacture of packaging materials for filling products such as pharmaceuticals, cosmetics, and foods, from the viewpoint of ease of molding and cost, and these plastic materials are It is produced from petroleum, a fossil resource. As plastic materials widely used as materials for packaging containers, polyester resins, polyolefin resins, polyamide resins, and the like are used. Among these, polyester resins are widely used in various industrial applications such as films, sheets, and packaging containers because they are excellent in mechanical properties, chemical stability, heat resistance, transparency and the like and are inexpensive.

  Polyester is obtained by polycondensation of a diol unit and a dicarboxylic acid unit. For example, polyethylene terephthalate (hereinafter sometimes abbreviated as PET) is obtained by esterifying both ethylene glycol and terephthalic acid as raw materials. After the polycondensation reaction. These raw materials are produced from petroleum which is a fossil resource, for example, ethylene glycol is produced industrially from ethylene and terephthalic acid is produced industrially from xylene.

In recent years, the use of alternative petroleum raw materials for various applications in consideration of the environment has been increasing year after year for such fossil fuel-derived materials, and in order to reduce CO ₂ emissions, we are moving away from fossil fuels. Is desired. As an attempt to reduce the use of fossil fuels, biomass plastics using biomass raw materials as part of various resin raw materials are being put into practical use as packaging materials. As an example, in polyester resins, those derived from biomass as ethylene glycol, which is a monomer component, have been put into practical use, and it is also proposed to apply polyester resins containing such biomass-derived raw materials to packaging materials. ing. For example, Patent Document 1 proposes a packaging film using a resin film containing polyester obtained using biomass-derived ethylene glycol and fossil fuel-derived dicarboxylic acid as a base material layer.

In addition, a method has been proposed in which a polyester resin collected from a used packaging material such as a PET bottle can be reused and recycled as a recycled polyester for molding of the packaging material (see, for example, Patent Documents 2 and 3). ). In Patent Documents 2 and 3, the amount of CO ₂ emissions is reduced by using polyester that has been collected from used products made of fossil fuel-derived polyester and can be reused as part of the packaging material. It has been proposed that

JP 2012-96469 A JP 2011-256328 A JP 2012-41463 A

As mentioned above, in order to reduce CO ₂ emissions, it has been attempted to use carbon-neutral materials as packaging materials for petroleum substitutes. In the future, packaging materials will be manufactured with consideration for the environment. Further departure from fossil fuels is desired. By the way, biomass polyester and recycled polyester have a higher CO ₂ emission reduction effect than fossil fuel polyester. Among them, recycled polyester has a higher CO ₂ emission reduction effect than biomass polyester. Recycled polyester has the highest CO ₂ emission reduction effect, but there is an impression that there is a possibility of contamination, etc., so packaging materials using recycled polyester film (recycled polyester film), especially food Even if a packaging material for filling a product such as the above is manufactured, it is difficult for consumers to obtain trust as a packaging material.

From such a technical background, the present inventors have now made the polyester film a film made of polyester comprising biomass polyester and recycled polyester, so that the entire polyester film is more fossil than unrecycled polyester. The inventors learned that the amount of fuel used can be reduced, the amount of CO ₂ emission can be further reduced, and a film having better hygiene than a recycled polyester film can be obtained. The present invention is based on this finding.

Accordingly, an object of the present invention is to provide a polyester film that is more excellent in CO ₂ reduction effect than non-recycled polyester and has better hygiene than recycled polyester.

  The polyester film according to the present invention is a single-layer polyester film, comprising biomass polyester derived from biomass as a diol unit, a biomass polyester containing a dicarboxylic acid derived from fossil fuel as a dicarboxylic acid unit, and a fossil fuel derived from a diol unit. And a recycled polyester obtained by recycling a polyester resin product containing a diol and / or biomass-derived ethylene glycol and a polyester containing a fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit.

  In the present invention, the total thickness of the polyester film is preferably 5 μm or more and less than 100 μm.

  In the present invention, the dicarboxylic acid is preferably terephthalic acid.

  A laminated film according to another aspect of the present invention includes any one of the above polyester films and a sealant layer provided on one or both sides of the polyester film.

According to the present invention, by forming a polyester film using biomass polyester and recycled polyester, the polyester film is more excellent in CO ₂ reduction effect than non-recycled polyester and more hygienic than recycled polyester. Can be provided.

It is a fragmentary sectional view which shows simply embodiment of the structure of the polyester film by this invention. It is sectional drawing which shows simply an example of a structure of the laminated film to which the polyester film by this invention is applied. It is a figure which shows simply an example of a structure of a standing pouch. It is a fragmentary sectional view of the laminated film which forms a trunk part. It is a fragmentary sectional view which shows an example of the other structure of the laminated | multilayer film which forms a trunk | drum. It is a figure which shows an example of a pillow bag simply. It is a figure which shows an example of a 3 way seal bag simply. It is a figure which shows an example of a 4-way seal bag simply. It is a fragmentary sectional view showing an example of a tube container simply. It is a fragmentary sectional view of the laminated film which forms the cylindrical trunk | drum of a tube container. It is a fragmentary sectional view showing an example of other composition of a lamination film which forms a cylindrical body part of a tube container. It is a perspective view which shows an example of a liquid paper container. It is a fragmentary sectional view which shows an example of a structure of the laminated | multilayer film used for a liquid paper container. It is the perspective view which excised a part of paper cup. It is a fragmentary sectional view which shows an example of a structure of the laminated | multilayer film used for the trunk | drum of a paper cup. It is explanatory drawing which showed an example of the outline of the manufacturing method of a paper cup.

Definition:
In this specification,
The “polyester” is obtained by a polycondensation reaction between a diol unit and a dicarboxylic acid unit.
The “fossil fuel polyester” is a diol derived from a fossil fuel-derived diol and a dicarboxylic acid derived from a fossil fuel-derived dicarboxylic acid.
“Biomass polyester” includes biomass-derived ethylene glycol as a diol unit and fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit, and biomass-derived ethylene glycol as a diol unit and a fossil fuel-derived dicarboxylic acid. May be formed only from a polyester having a dicarboxylic acid unit, or a biomass-derived ethylene glycol and a diol derived from fossil fuel as a diol unit, and a polyester having a dicarboxylic acid derived from fossil fuel as a dicarboxylic acid unit. May be.
“Recycled polyester” is obtained by recycling a polyester resin product containing a polyester containing fossil fuel-derived diol and / or biomass-derived ethylene glycol as a diol unit and fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit. Is.
"Recycled fossil fuel polyester" is obtained by recycling a polyester resin product formed using fossil fuel polyester.
“Recycled biomass polyester” is obtained by recycling a polyester resin product formed using biomass polyester.
“Polyethylene terephthalate (PET)” is a polyester in which ethylene glycol is a diol unit as a diol and terephthalic acid is a dicarboxylic acid unit as a dicarboxylic acid unit.
“Fossil fuel PET” is a diol in which ethylene glycol derived from fossil fuel is used as a diol and terephthalic acid derived from fossil fuel is used as a dicarboxylic acid unit as a dicarboxylic acid unit.
“Biomass PET” is an ethylene glycol derived from biomass as a diol as a diol unit and terephthalic acid derived from a fossil fuel as a dicarboxylic acid unit as a dicarboxylic acid unit.
“Mechanical Recycle PET” is obtained by recycling a polyester resin product containing polyester containing fossil fuel-derived diol and / or biomass-derived ethylene glycol as a diol unit and fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit. It is what

  DESCRIPTION OF EMBODIMENTS Hereinafter, modes for carrying out the present invention (hereinafter referred to as embodiments) will be described in detail. In addition, this invention is not limited by the following embodiment. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the constituent elements disclosed in the following embodiments can be appropriately combined. In the following description, one of the layers in the thickness direction may be referred to as “up” or “up”, and the other of the layers in the thickness direction may be referred to as “down” or “down”.

<Polyester film>
The polyester film according to the present invention will be described. The polyester film according to the present invention comprises biomass polyester and recycled polyester. FIG. 1 is a partial cross-sectional view schematically showing an embodiment of a polyester film according to the present invention. As shown in FIG. 1, the polyester film 10 is composed of a single layer polyester film. Moreover, the polyester film according to the present invention may further contain, for example, polyester such as fossil fuel polyester in addition to biomass polyester and recycled polyester.

  The total thickness of the polyester film according to the present invention is preferably 5 μm or more and less than 100 μm. If the total thickness of the polyester film according to the present invention is within the above range, it can be suitably used as a laminated film such as a package.

  The biomass polyester and the recycled polyester constituting the polyester film according to the present invention will be described.

[Biomass polyester]
The biomass polyester contains biomass-derived ethylene glycol as a diol unit and fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit. The ethylene glycol and dicarboxylic acid units that are diol units forming the biomass polyester will be described.

  Biomass-derived ethylene glycol uses ethanol (biomass ethanol) produced from biomass as a raw material. Biomass-derived ethylene glycol can be obtained from biomass ethanol by a conventionally known method, such as a method of producing ethylene glycol via ethylene oxide. Moreover, you may use the biomass ethylene glycol marketed, for example, the biomass ethylene glycol marketed by India Glycol company can be used conveniently.

  As the dicarboxylic acid unit, a dicarboxylic acid derived from fossil fuel is used. As the dicarboxylic acid, aromatic dicarboxylic acid, aliphatic dicarboxylic acid, and derivatives thereof can be used without limitation. Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, and phthalic acid. Examples of the aromatic dicarboxylic acid derivative include lower alkyl esters of aromatic dicarboxylic acid, specifically, methyl ester, ethyl ester, propyl ester, and butyl ester. Among these, terephthalic acid is preferable, and dimethyl terephthalate is preferable as an aromatic dicarboxylic acid derivative.

  Specific examples of the aliphatic dicarboxylic acid include oxalic acid, succinic acid, glutaric acid, 2,6-naphthalenedicarboxylic acid, adipic acid, sebacic acid, dodecanedioic acid, dimer acid, azelaic acid, dodecadicarboxylic acid, and Examples thereof include a chain or alicyclic dicarboxylic acid having usually 2 to 40 carbon atoms, such as cyclohexanedicarboxylic acid. Examples of the aliphatic dicarboxylic acid derivatives include lower alkyl esters such as methyl esters, ethyl esters, propyl esters, and butyl esters of the aliphatic dicarboxylic acids, and cyclic acid anhydrides of the aliphatic dicarboxylic acids such as succinic anhydride. . Among these, as the aliphatic dicarboxylic acid, adipic acid, succinic acid, dimer acid or a mixture thereof is preferable, and those having succinic acid as a main component are particularly preferable. As the derivative of the aliphatic dicarboxylic acid, methyl esters of adipic acid and succinic acid, or a mixture thereof are more preferable.

  These dicarboxylic acids can be used singly or in combination of two or more.

  The biomass polyester may be a copolymer polyester obtained by adding a copolymer component as a third component in addition to the diol unit and the dicarboxylic acid unit. Specific examples of the copolymer component include bifunctional oxycarboxylic acids, trifunctional or higher polyhydric alcohols, trifunctional or higher polyhydric carboxylic acids and / or their anhydrides, and 3 Examples include at least one polyfunctional compound selected from the group consisting of functional or higher oxycarboxylic acids. Among these copolymer components, a bifunctional and / or trifunctional or higher functional oxycarboxylic acid is particularly preferably used because a copolyester having a high degree of polymerization tends to be easily produced. Among them, the use of a tri- or higher functional oxycarboxylic acid is most preferable because a polyester having a high degree of polymerization can be easily produced with a very small amount without using a chain extender (coupling agent) described later.

  The biomass polyester may be a high molecular weight polyester obtained by chain extension (coupling) of these copolymer polyesters. As the coupling agent, a carbonate compound, a diisocyanate compound, or the like can be used, and the amount thereof is usually 10% for the carbonate bond and the urethane bond with respect to 100 mol% of all monomer units constituting the biomass polyester. The mol% or less, preferably 5 mol% or less, more preferably 3 mol% or less.

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

  Specific examples of the diisocyanate compound include 2,4-tolylene diisocyanate, a mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, and xylylene. Known diisocyanates such as range isocyanate, hydrogenated xylylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and the like can be mentioned.

  Biomass polyester can be obtained by a conventionally known method in which the above-described diol unit and dicarboxylic acid unit are polycondensed. Specifically, a general method of melt polymerization in which an esterification reaction and / or a transesterification reaction between the diol unit and the dicarboxylic acid unit is performed, and then a polycondensation reaction is performed under reduced pressure, or an organic solvent It can be produced by a known solution heating dehydration condensation method using

  The amount of the diol unit used in producing the biomass polyester is substantially equimolar with respect to 100 mol of the dicarboxylic acid or derivative thereof. Generally, esterification and / or transesterification and / or polycondensation are performed. Since there is distillation during the reaction, it is used in an excess of 0.1 to 20 mol%.

  The polycondensation reaction is preferably performed in the presence of a polymerization catalyst. The addition timing of 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 may be added at the start of pressure reduction.

  Examples of the polymerization catalyst generally include compounds containing a Group 1 to Group 14 metal element excluding hydrogen and carbon in the periodic table. Specifically, 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. Examples thereof include compounds containing an organic group such as a carboxylate, alkoxy salt, organic sulfonate, or β-diketonate salt, and inorganic compounds such as metal oxides and halides described above, and mixtures thereof. Among these, titanium, zirconium, germanium, zinc, aluminum, magnesium and calcium-containing metal compounds and mixtures thereof are preferable, and titanium compounds, zirconium compounds and germanium compounds are particularly preferable. In addition, since the polymerization rate of the catalyst is high when it is melted or dissolved during polymerization, a catalyst that is liquid during polymerization or is soluble in an ester low polymer or polyester is preferred.

  The titanium compound is preferably a tetraalkyl titanate, specifically, tetra-n-propyl titanate, tetraisopropyl titanate, tetra-n-butyl titanate, tetra-t-butyl titanate, tetraphenyl titanate, tetracyclohexyl titanate, tetra Examples include benzyl titanate and mixed titanates thereof. In addition, titanium (oxy) acetylacetonate, titanium tetraacetylacetonate, titanium (diisoproxide) acetylacetonate, titanium bis (ammonium lactate) dihydroxide, titanium bis (ethylacetoacetate) diisopropoxide, titanium (triethanolaminate) ) Isopropoxide, polyhydroxytitanium stearate, titanium lactate, titanium triethanolamate, butyl titanate dimer and the like 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 and 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 (for example, product name “C-94” manufactured by Acordis Industrial Fibers), particularly tetra-n-butyl titanate, polyhydroxy titanium stearate Rate, titanium (oxy) acetylacetonate, titanium tetraacetylacetonate, titania / silica composite oxide (eg, Acordis Industrial Fiber) The product name “C-94” manufactured by ers Inc.) is preferable.

  Specific examples of the zirconium compound include zirconium tetraacetate, zirconium acetylate hydroxide, zirconium tris (butoxy) stearate, zirconyl diacetate, zirconium oxalate, zirconyl oxalate, potassium potassium oxalate, and polyhydroxyzirconium. Examples include stearate, zirconium ethoxide, zirconium tetra-n-propoxide, zirconium tetraisopropoxide, zirconium tetra-n-butoxide, zirconium tetra-t-butoxide, zirconium tributoxyacetylacetonate and mixtures thereof. Further, zirconium oxide or a complex oxide containing, for example, zirconium and silicon may be used. Among these, zirconyl diacetate, zirconium tris (butoxy) stearate, zirconium tetraacetate, zirconium acetate acetate, zirconium ammonium oxalate, potassium potassium oxalate, polyhydroxyzirconium stearate, zirconium tetra-n-propoxy Zirconium tetraisopropoxide, zirconium tetra-n-butoxide, and zirconium tetra-t-butoxide are preferred.

  Specific examples of the germanium compound include inorganic germanium compounds such as germanium oxide and germanium chloride, and organic germanium compounds such as tetraalkoxygermanium. From the viewpoint of price and availability, germanium oxide, tetraethoxygermanium, tetrabutoxygermanium and the like are preferable, and germanium oxide is particularly preferable.

  The amount of the catalyst used in the case of using a metal compound as the polymerization catalyst is such that the lower limit is usually 5 ppm or more, preferably 10 ppm or more, and the upper limit is usually 30,000 ppm or less, preferably 1 as the amount of metal relative to the produced polyester. 1,000 ppm or less, more preferably 250 ppm or less, and particularly preferably 130 ppm or less. If too much catalyst is used, this is not only economically disadvantageous, but also lowers the thermal stability of the polymer. When the amount of the catalyst used is too small, the polymerization activity is lowered, and accordingly, the decomposition of the polymer is easily induced during the production of the polymer. As the amount of catalyst used, the amount of terminal carboxyl groups of the polyester to be produced is reduced as the amount used is reduced, and therefore the amount of catalyst used is preferably reduced.

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

  In the production process of biomass polyester, a coupling agent may be added to the reaction system. A high molecular weight biomass polyester using a coupling agent can be produced using a known method. After the polycondensation is completed, the coupling agent is added to the reaction system without solvent in a uniform molten state and reacted with the biomass polyester obtained by polycondensation. Specifically, the terminal group obtained by catalyzing a dicarboxylic acid unit and a diol unit has a hydroxyl group substantially, and a mass average molecular weight (Mw) is 20,000 or more, preferably 40,000 or more. A biomass polyester resin having a higher molecular weight can be obtained by reacting the above coupling agent with the biomass polyester prepolymer. If the prepolymer has an Mw of 20,000 or more, it is not affected by the remaining catalyst even under severe conditions such as a molten state by using a small amount of a coupling agent. High molecular weight biomass polyesters can be produced.

  The obtained biomass polyester may be solidified and then subjected to solid phase polymerization as necessary in order to further increase the degree of polymerization or to remove oligomers such as cyclic trimers. Specifically, after biomass polyester is chipped and dried, biomass polyester is pre-crystallized by heating at a temperature of 100 to 180 ° C for 1 to 8 hours, and subsequently at a temperature of 190 to 230 ° C. It is performed by heating for 1 hour to several tens of hours in an inert gas atmosphere or under reduced pressure.

  The inherent viscosity of the obtained biomass polyester is preferably 0.5 dl / g to 1.5 dl / g, more preferably 0.6 dl / g to 1.2 dl / g. When the intrinsic viscosity is less than 0.5 dl / g, mechanical properties required for a biomass polyester film as a transflective film substrate, including tear strength, may be insufficient. On the other hand, when the intrinsic viscosity exceeds 1.5 dl / g, productivity in the raw material manufacturing process and the film forming process is impaired. The intrinsic viscosity is measured at 35 ° C. with an orthochlorophenol solution.

  Various additives can be added to the resin composition containing biomass polyester as long as the characteristics thereof are not impaired in the production process or after the production. Examples of additives include plasticizers, UV stabilizers, anti-coloring agents, matting agents, deodorants, flame retardants, weathering agents, antistatic agents, yarn friction reducing agents, mold release agents, antioxidants, and ions. Examples include exchange agents and coloring pigments. It is preferable that an additive is added in 5-50 mass% with respect to the whole resin composition containing biomass polyester, Preferably it is 5-20 mass%.

The resin composition containing biomass polyester preferably contains 10 to 19% of the carbon derived from biomass as measured by radioactive carbon (C14) with respect to the total carbon in the biomass polyester. Since carbon dioxide in the atmosphere contains C14 at a constant ratio (105.5 pMC), the C14 content in plants that grow by incorporating carbon dioxide in the atmosphere, for example, corn, is also about 105.5 pMC. It is known. It is also known that fossil fuel contains almost no C14. Therefore, the proportion of carbon derived from biomass can be calculated by measuring the proportion of C14 contained in all carbon atoms in the biomass polyester. In the present invention, the content P _bio of the carbon derived from biomass when the content of C14 in the biomass polyester is PC ₁₄ is defined as the following formula (1).
P _bio (%) = P _C14 /105.5×100 (1)

For example, PET is obtained by polymerizing ethylene glycol containing 2 carbon atoms and terephthalic acid containing 8 carbon atoms in a molar ratio of 1: 1. Therefore, when only a diol unit derived from biomass is used as ethylene glycol, The content P _bio of the biomass-derived carbon in the polyester is 20%. In this embodiment, it is preferable that the content of carbon derived from biomass by radioactive carbon (C14) measurement is 10 to 19% with respect to the total carbon in the resin composition. When the carbon content derived from biomass in the resin composition is less than 10%, the effect as a carbon offset material becomes poor. On the other hand, as mentioned above, the biomass-derived carbon content in the resin composition is preferably closer to 20%, but from the viewpoint of problems in film production processes and physical properties, the resin composition contains an additive. Therefore, the actual upper limit is 18%.

That is, when only biomass-derived diol units are used as ethylene glycol, the biomass-derived carbon content _Pbio in the biomass polyester is 20%, and the biomass-derived carbon content is the total carbon in the resin composition. Therefore, the biomass polyester obtained using ethylene glycol derived from biomass as a diol unit and dicarboxylic acid derived from a petrochemical fuel as a dicarboxylic acid unit is based on the entire resin composition. 50 (= 10% / 20%) mass% to 95 (= 19% / 20%) mass% is preferably contained.

  The biomass polyester may partially include a polyester composed of fossil fuel-derived diol units and dicarboxylic acid units in addition to polyesters composed of biomass-derived ethylene glycol and dicarboxylic acid units as diol units. Examples of the diol unit derived from fossil fuel include ethylene glycol, propanediol, butanediol, pentanediol, hexanediol, neopentylglycol, 1,4-cyclohexanedimethanol, decanediol, and 2-ethyl-butyl-1-propane. Examples thereof include diol and bisphenol A. Further, as the dicarboxylic acid unit, for example, the above-mentioned dicarboxylic acid derived from fossil fuel can be used.

[Recycled polyester]
In the recycled polyester, the diol unit of the polyester to be recycled may be a diol derived from fossil fuel, may be ethylene glycol derived from biomass, or contains both diol derived from fossil fuel and ethylene glycol derived from biomass. But you can.

  As the biomass-derived ethylene glycol used in the resin that is the basis of the recycled polyester, the above-mentioned ones can be used. Moreover, the above-mentioned thing can be used also about the diol derived from a fossil fuel used for resin used as the origin of recycled polyester.

  The above-mentioned thing can be used also about the dicarboxylic acid unit used for resin used as the basis of recycle polyester.

  Moreover, the above-mentioned thing can be used also when it contains other components other than a diol unit and a dicarboxylic acid unit.

  In the present embodiment, mechanical recycling is used as a method for recycling resin products. Mechanical recycling is generally performed by crushing the collected polyester resin product such as PET bottles, washing with alkali to remove dirt and foreign matter on the surface of the polyester resin product, and then drying the polyester resin for a certain period of time at high temperature and reduced pressure. This is a method in which contaminants staying inside are diffused and decontaminated to remove stains on resin products made of polyester resin, and then returned to polyester resin again.

Biomass polyester and recycled polyester have a higher CO ₂ emission reduction effect than fossil fuel polyester, and recycled polyester has a higher CO ₂ emission reduction effect than biomass polyester. Therefore, by using recycled polyester, compared with the case where the polyester film is formed only from non-recycled polyester such as biomass polyester, the effect of reducing CO ₂ emission when producing the polyester film is increased. And the environmental load can be further reduced. Moreover, since recycled polyester is used by mixing with biomass polyester, the amount of recycled polyester that appears on the front and back surfaces of the polyester film according to the present invention can be reduced. Therefore, the polyester film according to the present invention is superior in hygiene compared to the case where the polyester film is formed only from recycled polyester.

  The polyester film according to the present invention comprises at least biomass polyester that is not recycled (hereinafter also referred to as virgin biomass polyester) and recycled polyester. The mass is preferably 1 to 85 parts by mass, and more preferably 30 to 50 parts by mass. If the mass of the recycled polyester is within the above range, the film can be stably produced while reducing the amount of fossil fuel used as the whole film.

  Further, the polyester film according to the present invention may contain a non-recycled fossil fuel polyester (hereinafter also referred to as virgin fossil fuel polyester) in addition to the biomass polyester and the recycled polyester.

(Production method of polyester film)
The polyester film according to the present invention can be produced by mixing and molding biomass polyester and recycled polyester. As a method of mixing the biomass polyester and the recycled polyester, there are a method of supplying them separately to a molding machine, a method of supplying them after mixing by dry blending, and the like. Among these, from the viewpoint that the operation is simple, a method of mixing by dry blend is preferable.

As described above, the polyester film according to the present invention is formed including at least biomass polyester and recycled polyester. Biomass polyester has a high CO ₂ emission reduction effect than fossil fuels polyester, recycled polyester is high further CO ₂ emission reduction effect than biomass polyester. Therefore, the polyester film according to the present invention is manufactured by using recycled polyester in addition to biomass polyester as part of the composition of the film, thereby packaging using non-recycled polyester such as virgin biomass polyester and virgin fossil fuel polyester. than the production of material may be CO ₂ emission reduction effect is higher polyester film. Moreover, since recycled polyester is used by mixing with biomass polyester, the amount of recycled polyester that appears on the front and back surfaces of the polyester film according to the present invention can be reduced. For this reason, when the polyester film according to the present invention is used as a packaging material for filling products such as food, it is possible to make the polyester film superior in hygiene compared to the case where the polyester film is formed only from recycled polyester. it can.

Here, when the total thickness of the polyester film was the same, the reduction rate of the CO ₂ emission amount was compared for the polyester film of this embodiment and the polyester film of the comparative form. In Table 1, the structure and composition of the polyester film of this embodiment and the polyester film of a comparative form are shown. The configuration of the PET resin of each composition of Compositions 1 to 3 shown in Table 1 and the configurations of the polyester film of the present embodiment and the polyester film of the comparative embodiment are as follows. The “PET resin” used below is a resin made of polyethylene terephthalate (PET), the “fossil fuel PET resin” is a resin made of fossil fuel PET, and the biomass PET resin is biomass PET. The “mechanically recycled PET resin” is a resin made of mechanically recycled PET.
(Composition 1)
This is an unrecycled biomass PET resin (hereinafter, also referred to as virgin biomass PET resin) obtained using ethylene glycol derived from biomass and terephthalic acid derived from fossil fuel.
(Composition 2)
This is a mechanically recycled PET resin obtained by mechanically recycling PET obtained using ethylene glycol derived from fossil fuel and terephthalic acid derived from fossil fuel.
(Composition 3)
This is a non-recycled fossil fuel PET resin (hereinafter also referred to as virgin fossil fuel PET resin) obtained by using ethylene glycol derived from fossil fuel and terephthalic acid derived from fossil fuel.
(This embodiment)
The polyester film of this embodiment is a single layer, and is composed of a PET resin obtained by blending 67% virgin biomass PET resin of composition 1 and 33% of mechanically recycled PET resin of composition 2.
(Comparative form 1)
The polyester film of comparative form 1 is a single layer and is composed of 100% virgin fossil fuel PET resin of composition 3, and corresponds to non-recycled fossil fuel PET (hereinafter also referred to as virgin fossil fuel PET). To do.
(Comparative form 2)
The polyester film of comparative form 2 is a single layer, and is composed of PET resin obtained by blending 67% of virgin biomass PET resin of composition 1 and 33% of virgin fossil fuel PET resin of composition 3, and is not recycled biomass PET (hereinafter, Equivalent to Virgin Biomass PET).
(Comparative form 3)
The polyester film of comparative form 3 is a single layer and is composed of 100% mechanically recycled PET resin of composition 2, and corresponds to mechanically recycled PET.

Table 2 shows the results of calculating the CO ₂ emission for the polyester film of this embodiment and the polyester films of Comparative Examples 1 to 3. As can be seen from Table 2, the polyester film of this embodiment, about 24% compared to the polyester film of Comparative Embodiment 1, is about 15% CO ₂ emissions is small value compared to a polyester film of Comparative Embodiment 2 Yes. The polyester film of this embodiment has higher CO ₂ emissions than the polyester film of comparative form 3, but contains biomass PET that has not been recycled in part of the polyester film, so it is more than the polyester film of comparative form 3. Also excellent in hygiene.

<Laminated film>
Next, the laminated film to which the polyester film according to the present invention is applied will be described. The laminated film to which the polyester film according to the present invention is applied has the polyester film according to the present invention and a sealant layer provided on one or both sides of the polyester film according to the present invention. FIG. 2 is a cross-sectional view schematically showing an example of the configuration of a laminated film to which the polyester film according to the present invention is applied. As shown in FIG. 2, the laminated film 20 includes a polyester film 10 and a sealant layer 21, and is configured by laminating the sealant layer 21 on the polyester film 10. In the embodiment shown in FIG. 2, the laminated film 20 has a configuration in which the sealant layer 21 is laminated above the surface of the polyester film 10, but the laminated film 20 has a sealant layer below the surface of the polyester film 10. 21 may be laminated, and a sealant layer 21 may be provided on both the upper and lower sides of the surface of the polyester film 10.

  In addition to the sealant layer 21, the laminated film 20 may have at least one other layer such as a barrier layer, a support, a resin layer, and a printing layer above and / or below the surface of the polyester film 10. Good. The explanation of these other layers will be described later.

  As shown in FIG. 2, the sealant layer 21 is provided on the surface of the polyester film 10 of the laminated film 20. The sealant layer 21 is a layer formed of a heat-sealable resin film that can be fused to each other by heat.

  The material for forming the sealant layer 21 is not particularly limited as long as it is a resin that can be fused to each other by heat. Specifically, for example, low density polyethylene (LDPE), medium density polyethylene (MDPE), high Density polyethylene (HDPE), linear (linear) low density polyethylene (LLDPE), ethylene-α-olefin copolymer polymerized using a metallocene catalyst, ethylene-polypropylene random or block copolymer, polypropylene, Ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate Copolymer (EMMA), ionomer resin, heat sealable ethylene Alcohol resin or copolymerized resin Methylpentene resin, ethylene-propylene copolymer, methylpentene polymer, polybutene polymer, polyolefin resin such as polyethylene, polypropylene or cyclic olefin copolymer, polyolefin resin such as acrylic acid, methacrylic resin Acid-modified polyolefin resins modified with unsaturated carboxylic acids such as acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, polyvinyl acetate resins, poly (meth) acrylic resins, polyvinyl chloride resins, etc. And the like. These may be used alone or as a mixture of two or more. The sealant layer 21 can be used as a resin film or sheet as described above, or a coating film thereof.

  When polyethylene is used as a material for forming the sealant layer 21, a raw material obtained by polymerizing ethylene derived from biomass in addition to ethylene obtained from fossil fuel may be used. Specifically, as the ethylene derived from biomass, for example, those described in JP 2012-251006 A can be used. By using polyethylene obtained by polymerizing ethylene derived from biomass as a material constituting the sealant layer 21, a layer made of a carbon neutral material can be used. By using together with polyester, the amount of fossil fuel used can be greatly reduced, and the environmental load can be reduced.

  Commercially available ethylene may be used as biomass-derived ethylene, for example, “C4LL-LL118 (d = 0.916, MFR = 1.0 g / 10 min)” made by Braschem Co. A low density polyethylene resin can be used.

  In the present embodiment, the sealant layer 21 is a single layer, but two or more sealant layers 21 may be provided. When two or more sealant layers 21 are included, each may have the same composition or a different composition.

  As thickness of the sealant layer 21, 20-200 micrometers is preferable and 30-130 micrometers is more preferable.

  Examples of a method for laminating the sealant layer 21 on the upper surface side (inner surface side) of the laminated film 20 include a dry lamination method and a melt extrusion lamination method. Moreover, when performing said lamination | stacking, pre-treatments, such as a corona treatment, an ozone treatment, a flame treatment, etc., can be given to a film as needed. Of these, the dry lamination method is more preferable because of its excellent adhesive strength.

  Moreover, in this embodiment, although the laminated | multilayer film 20 is set as the structure provided with the polyester film 10 and the sealant layer 21, it is not limited to this, If the laminated film 20 is provided with these layers, In addition to the polyester film 10 and the sealant layer 21, at least one other layer may be included. For example, the laminated film 20 is formed by laminating the polyester film 10 and the sealant layer 21, the surface of the sealant layer 21 opposite to the surface on which the polyester film 10 is laminated, or the sealant layer 21 of the polyester film 10. Depending on the form of the package, another layer may be provided on the surface opposite to the surface side.

  Examples of other layers include a barrier layer, a support, a resin layer, and a printing layer. When two or more other layers are included, each may have the same composition or a different composition. These other layers can be laminated together via an adhesive layer by a dry lamination method or via an adhesive resin layer by a melt extrusion lamination method.

  The barrier layer functions as a layer having gas barrier properties that prevent permeation of gas such as oxygen gas or water vapor barrier properties that prevent permeation of water vapor and the like. Examples of the barrier layer include a layer made of a metal foil obtained by rolling a metal such as an aluminum foil, a layer made of a vapor deposited film of a metal such as aluminum, a layer made of a vapor deposited film of an inorganic oxide such as alumina, and a gas barrier property. A layer made of a coating film, a saponified ethylene-vinyl acetate copolymer (EVOH), or the like can also be used. Further, when the barrier layer is formed of a layer made of an inorganic oxide vapor-deposited film such as alumina, the layer made of the gas barrier coating film is formed from the inorganic oxide vapor-deposited film in order to impart or improve gas barrier properties. It may be provided on at least one surface of the layer to be formed. The barrier layer can be formed by a conventionally known method, and its composition and formation method are not particularly limited. Specifically, as the metal foil and vapor deposition film constituting the barrier layer, for example, those described in JP 2012-96469 A can be used. The gas barrier coating film is a film obtained by polycondensation by a sol-gel method, containing one or more alkoxides and a polyvinyl alcohol resin and / or an ethylene / vinyl alcohol copolymer. For example, those described in JP 2012-96469 A can be used. Specifically, as EVOH constituting the barrier layer, for example, those described in JP-A-2008-307847 can be used. Two or more barrier layers may be provided. When two or more barrier layers are provided, each may have the same composition or a different composition. One or more barrier layers may be provided on both sides of the polyester film 10.

  The support supports the laminated film 20 such as a stretched polyester-based resin layer, a stretched polyamide-based resin layer, a stretched polyolefin-based resin layer, and a paper base material (paper layer), and provides strength properties and impact resistance of the laminated film 20. If it can improve, it will not specifically limit, It can form using a well-known thing. Moreover, you may use the material derived from biomass as a support body. Moreover, a support body can use these layers individually or in combination of 2 or more layers.

  As the polyester-based resin layer that can be used as the support, biomass-derived polyesters can be used in addition to conventionally known fossil fuel-derived polyesters. The polyester-based resin layer may be a layer formed by mixing a resin material containing a conventional fossil fuel-derived raw material and a resin material containing a biomass-derived raw material.

  In addition, in order to improve adhesiveness, you may use what contains a sulfonic acid group containing dicarboxylic acid as a dicarboxylic acid component. Examples of the sulfonic acid group-containing dicarboxylic acid include a sulfonic acid metal salt-containing dicarboxylic acid. Examples of the dicarboxylic acid containing a sulfonic acid metal salt include metals such as sulfoterephthalic acid, 5-sulfoisophthalic acid, 4-sulfophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, and 5- [4-sulfophenoxy] isophthalic acid. And salts (alkali metal salts, alkaline earth metal salts, etc.). In particular, from the viewpoint of obtaining good adhesion and deformation resistance, it is preferable to use sodium sulfoterephthalic acid or 5-sodium sulfoisophthalic acid. In the sulfone group-containing polyester, the copolymerization ratio of the sulfonic acid group-containing dicarboxylic acid is preferably 0.5 to 10 mol% with respect to the total acid component. Further, the intrinsic viscosity is preferably 0.3 to 0.8 dl / g.

  Various polyester resins can be used according to the use of the package including the laminated film to which the polyester film according to the present invention is applied, and a mixture of two or more kinds may be used. For example, when polyester is used, a support having excellent thermal dimensional stability, fragrance retention and heat resistance can be obtained. Moreover, when using a sulfone group containing polyester, the coextruded film which has high interlayer adhesive strength is obtained.

  The polyester resin layer may contain various additives such as a lubricant as required.

  Moreover, as a polyamide-type resin layer which can be used as a support body, you may mainly use aliphatic polyamide, but you may contain other polyamide components, for example, aromatic polyamide etc. Examples of the aliphatic polyamide include hexamethylene diamine, decamethylene diamine, dodecamethylene diamine, 2,2,4- or 2,4,4-trimethylhexamethylene diamine, 1,3- or 1,4-bis (amino Aliphatic and alicyclic diamines such as methyl) cyclohexane and bis (p-aminocyclohexylmethane), and dicarboxylic acids such as adipic acid, suberic acid, sebacic acid, cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid and the like Aliphatic polyamides obtained by polycondensation reaction with derivatives, polyamide resins obtained by condensation of ε-aminocaproic acid, 11-aminoundecanoic acid, polyamide resins obtained from lactam compounds such as ε-caprolactam, ω-laurolactam, Or a mixture of these It can be used. Specifically, for example, an aliphatic polyamide resin such as nylon 6, nylon 6,6, nylon 9, nylon 11, nylon 12, nylon 6/66, nylon 66/610, nylon MXD6 can be used. Among them, suitable aliphatic polyamides include nylon 6, nylon 6,6, nylon-6 / 6,6 and the like. Examples of the two or more aliphatic polyamides include combinations of nylon 6 and nylon 6/6, 6 in any ratio.

  Examples of the stretched polyolefin resin layer that can be used as a support include low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), and linear (linear) low density polyethylene. (LLDPE), polypropylene (PP), an ethylene-α-olefin copolymer polymerized using a metallocene catalyst, a random or block copolymer of ethylene-polypropylene, and the like can be used.

  When formed using a polyester-based resin layer or a polyamide-based resin layer as a support, in order to improve the adhesion of the support to the sealant layer 21, a modified polyolefin is interposed between the support and the sealant layer 21. A modified polyolefin-based resin layer may be provided. The modified polyolefin is modified by a method such as replacing a part of the main component polyolefin with another substance (monomer) by copolymerization or cocondensation, or reacting an appropriate substance (monomer) locally. Polyolefin resin. Specifically, for example, low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear (linear) low density polyethylene (LLDPE), ethylene polymerized using a metallocene catalyst -Α-olefin copolymer, polypropylene (PP), ethylene-vinyl acetate copolymer (EVA), ionomer resin, ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), Polyolefin resins such as ethylene-methacrylic acid copolymer (EMAA), ethylene-propylene copolymer, methylpentene polymer, polyethylene, polyethylene resin, or polypropylene resin, acrylic acid, methacrylic acid, maleic anhydride, Modified with fumaric acid or other unsaturated carboxylic acid Acid-modified polyolefin-based resin and the like. In addition, it cannot be overemphasized that what uses the above-mentioned ethylene derived from biomass as a monomer unit can be used as above-mentioned polyethylene-type resin.

  A preferable modified polyolefin is a copolymer having a structure in which a polyolefin segment and a segment having a polarity other than olefin are bonded in a block shape and / or a graft shape and / or a random shape, such as a propylene-based polyolefin segment. A copolymer of ethylene and a segment containing lactic acid as a constituent component, a copolymer of an ethylene-based polyolefin segment and a segment containing an acrylic acid unit as a constituent component, a propylene-based polyolefin segment and a segment containing an acrylic acid unit as a constituent component A copolymer etc. are mentioned. Specifically, for example, ADMER SE800, SF740, SF731, and SF730 manufactured by Mitsui Chemicals, Inc. can be used as the maleic anhydride-modified polyolefin resin.

  Moreover, as a material derived from biomass constituting the support, in addition to the above, a commercially available polylactic acid film may be used. For example, a polylactic acid film sold by Mitsui Chemicals, Inc. Can be used.

  Moreover, as a paper base material (paper layer) that can be used as a support, any paper can be used depending on the desired rigidity, for example, fine paper, imitation paper, art paper, coated paper, Uses well-known paper such as pure white roll paper, kraft paper, water-resistant label paper, cup base paper, card paper, ivory paper, paperboard such as Manila ball, milk carton base paper, cup base paper, synthetic paper, clay coat paper can do.

  The thickness of the above-described polyester-based resin layer or the like as the support may be appropriately adjusted depending on the use application of the laminated film. For example, when the laminated film is used as a packaging material for applications where rigidity is required, it is thick. It can be a support.

  Moreover, a support body becomes a layer which consists of carbon neutral resin by forming a support body using the resin material containing the raw material derived from biomass. A laminated film having two or more layers made of a carbon neutral resin can be produced by forming the laminated film with a layer made of the polyester film 10 and the support made of a carbon neutral resin. Thereby, the usage-amount of the fossil fuel used for formation of a support body can be reduced significantly, and an environmental load can be reduced.

  A conventionally known method can be used as the method for forming the support, and it is not particularly limited. The support may be formed by extruding and laminating these materials, or laminated on the printed layer using a dry laminating method or the like as a film formed in advance using a T-die method or an inflation method. May be.

  A printing layer can be provided as needed, for example, can be provided between the polyester film 10 and a support body. The print layer can be any desired printed pattern such as characters, pictures, figures, symbols, patterns, etc. for decoration, content display, best-of-life display, manufacturer, seller display, etc. It is a layer which forms. The printing layer may be provided on the entire surface or may be provided on a part.

  The printing layer can be formed using conventionally known pigments and dyes, and contains one or more ordinary ink vehicles as a main component, and if necessary, a plasticizer, a stabilizer, an antioxidant, a light One or more additives such as stabilizers, UV absorbers, curing agents, cross-linking agents, lubricants, antistatic agents, fillers, etc. can be optionally added, and colorants such as dyes and pigments can be added. Ink compositions obtained by sufficiently kneading with a solvent, a diluent or the like can be used.

  As the above-mentioned ink vehicle, known ones such as sesame oil, drill oil, soybean oil, hydrocarbon oil, rosin, rosin ester, rosin modified resin, shellac, alkyd resin, phenolic resin, maleic acid resin, natural resin Resin, hydrocarbon resin, polyvinyl chloride resin, polyacetic acid resin, polystyrene resin, polyvinyl butyral resin, acrylic or methacrylic resin, polyamide resin, polyester resin, polyurethane resin, epoxy resin, urea resin, One or more of melamine resin, aminoalkyd resin, nitrocellulose, ethylcellulose, chlorinated rubber, cyclized rubber, etc. can be used in combination.

  The formation method of a printing layer is not specifically limited, For example, normal printing methods, such as gravure printing, offset printing, letterpress printing, screen printing, transfer printing, flexographic printing, etc., can be used. A printing layer can be formed by printing a desired printing pattern on the outer surface side of a support using the ink layer forming method.

The coating amount of the ink composition is preferably 1μm~8μm position in the dry state after coating, and more preferably 2g / m ² ~3g / m ² in the coating unit.

  The print layer is preferably formed after surface treatment is previously performed on the print layer forming side of the support. Examples of such surface treatment include corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, oxidation treatment using chemicals, and other pretreatments. is there. In addition, a primer coating agent, an undercoat agent, an anchor coating agent, or the like can be arbitrarily applied in advance and surface-treated.

The adhesive layer provided when two layers are bonded by the dry lamination method can be formed by applying an adhesive (laminating adhesive) used for laminating to the surface of the layer to be laminated and drying it. . Examples of laminating adhesives include one-part or two-part cured or non-cured vinyl, (meth) acrylic, polyamide, polyester, polyether, polyurethane, epoxy, and rubber. Other types of adhesives such as a solvent type, an aqueous type, and an emulsion type can be used. As a coating method of the above laminating adhesive, for example, a laminated film is constituted by a direct gravure roll coating method, a gravure roll coating method, a kiss coating method, a reverse roll coating method, a fountain method, a transfer roll coating method, and other methods. It can apply | coat to the application surface of a layer. The coating ^{amount, 0.1g / m 2 ~10g / m} 2 ( dry) are ^{preferred, 1g / m 2 ~5g / m} 2 ( dry) is more preferable.

  The adhesive resin layer provided when two layers are bonded by the melt extrusion lamination method is formed by a melt extrusion lamination method using a thermoplastic resin. Examples of the thermoplastic resin that can be used for the adhesive resin layer include a polyethylene resin, a polypropylene resin, or a cyclic polyolefin resin, or a copolymer resin, a modified resin, or a mixture (including alloy) containing these resins as a main component. ) Can be used. Examples of polyolefin resins include low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear (linear) low density polyethylene (LLDPE), polypropylene (PP), and metallocene catalysts. Ethylene-α / olefin copolymer, ethylene / polypropylene random or block copolymer, ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene Ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ethylene / maleic acid copolymer, ionomer resin, and interlayer adhesion In order to improve the , It can be used acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and an acid-modified polyolefin resin modified with an unsaturated carboxylic acid such as itaconic acid. Further, a resin obtained by graft polymerization or copolymerization of an unsaturated carboxylic acid, an unsaturated carboxylic acid anhydride, or an ester monomer can be used as the polyolefin resin. These materials can be used alone or in combination of two or more. As the cyclic polyolefin-based resin, for example, cyclic polyolefins such as ethylene-propylene copolymer, polymethylpentene, polybutene, and polynorbornene can be used. These resins can be used alone or in combination. In addition, it cannot be overemphasized that what uses the above-mentioned ethylene derived from biomass as a monomer unit can be used as above-mentioned polyethylene-type resin.

  For the adhesive resin layer, if necessary, for example, film processability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slipperiness, mold release properties, flame retardancy, antifungal properties Various plastic compounding agents and additives can be added for the purpose of improving and modifying electrical characteristics, strength, etc. The amount of addition can be from a very small amount to several tens of percent. Depending on the case, it can be added arbitrarily. In the above, as general additives, for example, coloring of lubricants, plasticizers, fillers, antistatic agents, antiblocking agents, crosslinking agents, antioxidants, ultraviolet absorbers, light stabilizers, dyes, pigments, etc. An agent or the like can be used, and a modifying resin can also be used.

  The thickness of the adhesive resin layer can be appropriately set within a range of usually 5 to 800 μm, preferably 10 to 500 μm. If the thickness is less than this range, the moisture barrier property is insufficient, and if it is more than this range, the quality becomes excessive and the moldability also deteriorates.

  In the case of laminating the adhesive resin layer on the surface of the polyester film 10 by a melt extrusion lamination method using a polyolefin resin having a polar group such as the acid-modified polyolefin resin as described above as the adhesive resin layer, The adhesive resin layer can be laminated without performing a surface treatment such as an anchor coating agent.

  Also, one or both surfaces of the laminated film 20 have chemical functions, electrical functions, magnetic functions, mechanical functions, friction / abrasion / lubricating functions, optical functions, thermal functions, biocompatibility, etc. Secondary processing can be performed for the purpose of imparting surface functions and the like. Examples of secondary processing include, for example, embossing, painting, adhesion, printing, metalizing (plating, etc.), machining, surface treatment (antistatic treatment, corona discharge treatment, plasma treatment, photochromism treatment, physical vapor deposition, chemical Vapor deposition, coating, etc.). Moreover, the laminated film 20 can be subjected to laminating (dry laminating or extrusion laminating), bag-making, and other post-processing to produce a molded product such as a package.

Thus, the laminated film 20 is a film provided with the polyester film 10 and the sealant layer 21, and the polyester film 10 is formed of a layer made of a carbon neutral material and is excellent in hygienic properties. By using 20 as a packaging material, the amount of fossil fuel used as a whole film can be reduced, and a laminated film having a high CO ₂ emission reduction effect and excellent hygiene can be realized.

<Packaging body>
The laminated film to which the polyester film according to the present invention is applied is useful as a packaging material for foods and the like because it reduces the amount of fossil fuel used, has a high CO ₂ emission reduction effect, and is excellent in hygiene. For example, it can be suitably used as a packaging film for a package. Examples of the package include a packaged product (packaging bag), a lid material, a laminate tube, a liquid container, a paper cup, and various label materials. As packaging bags, for example, standing pouch type, side seal type, two-side seal type, three-side seal type, four-side seal type, envelope-attached seal type, joint-attached seal type (pillow seal type), pleated seal type, flat bottom seal type And various forms of packaging bags such as a square bottom seal type and a gusset type. The thickness of the laminated film can be appropriately determined according to the application. For example, it is used in the form of a film having a thickness of 30 to 300 μm, preferably 35 to 180 μm. An example of a package using a laminated film to which the polyester film according to the present invention is applied will be described below. In addition, in this embodiment, although each layer other than the sealant layer 21 of the package illustrated below is made into one layer, it is not limited to this, You may have two or more layers. Moreover, although the package body illustrated below is provided with the printing layer, it is not limited to this, The printing layer does not need to be provided.

[Standing pouch]
The case where the laminated film which applied the polyester film by this invention is applied to a standing pouch is demonstrated. FIG. 3 is a diagram schematically illustrating an example of a configuration of a standing pouch. As shown in FIG. 3, the standing pouch 30 includes two body parts (side sheet) 31 and a bottom part (bottom sheet) 32. In the standing pouch 30, the side sheet 31 and the bottom sheet 32 are configured as separate members. The standing pouch 30 is a package formed by bag making so that the sealant layer of the laminated film constituting the side sheet 31 becomes the innermost layer. In the present embodiment, the standing pouch 30 includes the side sheet 31 and the bottom sheet 32 as separate members, but is not limited thereto, and the side sheet 31 and the bottom sheet 32 are the same member. It may be comprised.

  The side sheet 31 can be formed using a laminated film to which the polyester film according to the present invention is applied. FIG. 4 is a partial cross-sectional view of the laminated film forming the body portion. As shown in FIG. 4, the laminated film 20 </ b> B forming the side sheet 31 includes, for example, a sealant layer 21, a support 33, a printing layer 34, and a polyester film 10, and the sealant layer 21, the support 33, and the printing layer 34. And the polyester film 10 can be laminated in this order from the inner surface side to the outer surface side. The standing pouch 30 is manufactured by heat-sealing and bonding the sealant layers 21 of the side sheets 31 to each other. In the laminated film 20B, the barrier layer may be provided between any of the layers constituting the laminated film 20B, for example, between the polyester film 10 and the print layer 34.

  In the present embodiment, the print layer 34 is provided between the polyester film 10 and the support 33. However, when the support 33 is transparent, the print layer 34 is the sealant layer 21 and the support. 33 may be provided.

  Moreover, in this embodiment, although the side sheet 31 is formed using the laminated | multilayer film which applied the polyester film by this invention, it is not limited to this, The bottom sheet 32 is polyester by this invention. The laminated film to which the film is applied may be used, or both the side sheet 31 and the bottom sheet 32 may be formed using the laminated film to which the polyester film according to the present invention is applied.

  Further, the laminated film 20B forming the side sheet 31 is not limited to the layer configuration as shown in FIG. 4, and may have the layer configuration shown in FIG. 2 or other layers as described above. You may use what comprises. Moreover, according to the material which comprises the support body 33, you may change each layer suitably in arbitrary positions, for example, as shown in FIG. 5, the laminated film 20C which forms the side sheet 31 is the sealant layer 21, The laminated film 20 </ b> C includes a polyester film 10, a support 33, and a printed layer 34, and a laminated film 20 </ b> C has a layer configuration in which the sealant layer 21, the polyester film 10, the support 33, and the printed layer 34 are laminated in this order from the inner surface to the outer surface. It may be. Also in the laminated film 20C, the barrier layer may be provided between any of the layers constituting the laminated film 20C, for example, between the polyester film 10 and the sealant layer 21.

  The standing pouch 30 can be manufactured using a conventionally known manufacturing method. For example, the two side sheets 31 are overlapped with the side sheets 31 facing each other so that the sealant layer 21 is the innermost layer, The bottom sheet 32 is inserted between the two side sheets 31, and the side sheet 31 and the bottom sheet 32 are heat sealed.

  As a heat sealing method, for example, a known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, or an ultrasonic seal can be used.

  The standing pouch 30 is a packaging bag filled with liquid, for packaging chemical products, pharmaceuticals, quasi-drugs, cosmetics, foods, etc., for example, as an outer bag for patches, or as a liquid detergent, liquid softener, It can be suitably used as a standing pouch used for refill contents such as liquid soap.

  Moreover, according to the form which heat-seals a laminated | multilayer film, it can be set as various packaging bags other than a standing pouch. FIG. 6 is a diagram schematically illustrating an example of a pillow bag, FIG. 7 is a diagram schematically illustrating an example of a three-way seal bag, and FIG. 8 is a diagram schematically illustrating an example of a four-way seal bag. is there. In addition, in FIGS. 6-8, the heat seal location is displayed by hatching. As shown in FIG. 6, the pillow bag 41 is formed so that the sealant layer 21 of the laminated films 20 </ b> A to 20 </ b> C as shown in FIG. 2, FIG. 4, and FIG. It can be obtained by heat-sealing and bonding the two surfaces. Further, as shown in FIG. 7, the three-side seal bag 42 is formed by stacking the bags so that the sealant layer 21 of the laminated films 20 </ b> A to 20 </ b> C as shown in FIGS. 2, 4, and 5 is the innermost layer. It is obtained by heat-sealing and adhering the three sides of the films 20A to 20C. Further, as shown in FIG. 8, the four-side seal bag 43 is formed and laminated so that the sealant layer 21 of the laminated films 20 </ b> A to 20 </ b> C as shown in FIGS. 2, 4, and 5 is the innermost layer. It is obtained by heat-sealing and adhering the four sides of the film 20.

[Cover material]
Next, the case where a cover material is formed using the laminated | multilayer film to which the polyester film by this invention is applied is demonstrated. The lid material is a case where the support 33 constituting the laminated film is constituted by a paper layer, and can be formed using laminated films 20A to 20C having a layer structure as shown in FIGS. 2, 4 and 5. it can.

  The lid is made of cup-shaped packaging containers, especially instant foods that are poured into hot water such as cup ramen and cup fried noodles, foods heated in microwave ovens, other instant foods, heated beverages, and heated in microwave ovens It can be suitably used as a lid for packaging containers for sealing contents such as beverages, snacks, confectionery, and jelly.

[Tube container]
Next, the case where a tube container is formed using the laminated | multilayer film to which the polyester film by this invention is applied is demonstrated. FIG. 9 is a partial cross-sectional view schematically showing an example of a tube container. As shown in FIG. 9, the tube container 50 includes a head 51 and a cylindrical body 52.

  The head 51 includes a hollow conical shoulder 53 and a spout 54 and is integrally formed.

  The cylindrical body 52 is connected to the shoulder 53 of the head 51. The cylindrical trunk | drum 52 can be formed using a laminated film. FIG. 10 shows a partial cross-sectional view of the laminated film that forms the cylindrical body of the tube container. As shown in FIG. 10, the laminated film 20D forming the cylindrical body 52 includes a first sealant layer 21A, a polyester film 10, a print layer 34, and a second sealant layer 21B, and the first sealant layer 21A, the polyester film 10, the printing layer 34, and the second sealant layer 21B are laminated in this order from the inner surface side to the outer surface side of the cylindrical body portion 52. In addition, the laminated film 20D may be provided with the barrier layer between any of the layers constituting the laminated film 20D, for example, between the polyester film 10 and the printing layer 34.

  Further, the laminated film 20D forming the cylindrical body 52 is not limited to the layer configuration as shown in FIG. 10, and the layer configuration of the laminated film 20D can be arbitrarily adjusted as appropriate. An example of another layer configuration of the laminated film forming the cylindrical body 52 is shown in FIG. As shown in FIG. 11, the laminated film 20 </ b> E that forms the cylindrical body 52 is provided with an adhesive resin layer 55 between the polyester film 10 and the printing layer 34 in the laminated film 20 </ b> D shown in FIG. 10. A support 33 is provided between the second sealant layer 21 and the second sealant layer 21B. Also in the laminated film 20E, the barrier layer may be provided between any of the layers constituting the laminated film 20E, for example, between the polyester film 10 and the adhesive resin layer 55.

  The cylindrical body 52 is produced by superimposing the first sealant layer 21A and the second sealant layer 21B on both ends of the cylindrical body 52, and heat-sealing and welding the overlapped portions. . The cylindrical body 52 has a head 51 connected to the upper part of one opening thereof. In addition, the both ends of the cylindrical trunk | drum 52 are not limited to the method of superimposing the 1st sealant layer 21A and the 2nd sealant layer 21B, Even if it overlaps the 2nd sealant layer 21B. Good.

  As a heat sealing method, a conventionally known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, an ultrasonic seal, or a flame seal can be used.

  An example of the manufacturing method of the tube container 50 is demonstrated. The head 51 is connected to one opening of the cylindrical body 52 by, for example, a normal method such as compression molding. Thereafter, the contents are filled from the other open end connected to the head portion 51 of the cylindrical body portion 52, and the open end is thermally welded to form the bottom seal portion 56. Thereby, the tube container 50 filled and packaged with the contents can be obtained. A cap can be attached to the spout portion 54 by various methods, such as screwing or fitting, according to the shape of the spout portion 54.

  The tube container 50 can be suitably used as, for example, a tube container for toothpaste, cosmetics, glue, paste hot pepper, paste wasabi, cream, paint, cartilage, pharmaceuticals, and other conventionally known products.

[Liquid paper container]
Next, the case where a liquid paper container is formed using the laminated | multilayer film to which the polyester film by this invention is applied is demonstrated. FIG. 12 is a perspective view showing an example of a liquid paper container. As shown in FIG. 12, the liquid paper container 60 has a square cylindrical body 61 including a side surface, a square plate-shaped bottom portion 62, and an upper portion 63.

  The upper part 63 includes a pair of opposed inclined plates 63a and a pair of folding portions 64 that are located between the inclined plates 63a and are folded between the inclined plates 63a. The pair of inclined plates 63a is provided with a margin 65 at each upper end, and the pair of inclined plates 63a are bonded to each other by a margin 65 provided at each upper end. Note that a spout may be attached to one inclined plate 63a of the pair of inclined plates 63a, and the spout may be sealed with a cap.

  The liquid paper container 60 can be formed using a laminated film. FIG. 13 is a cross-sectional view showing an example of the configuration of a laminated film used in a liquid paper container. As shown in FIG. 13, the laminated film 20F forming the liquid paper container 60 includes a first sealant layer 21A, a polyester film 10, an adhesive resin layer 55, a paper base material (paper layer) 66, and a second sealant layer 21B. The first sealant layer 21A, the polyester film 10, the adhesive resin layer 55, the paper layer 66, the second sealant layer 21B, and the print layer 34 are arranged from the inner surface side of the liquid paper container 60 to the outer surface. The layers can be laminated in this order toward the side. Further, the laminated film 20F may be provided with the barrier layer between any of the layers constituting the laminated film 20F, for example, between the polyester film 10 and the adhesive resin layer 55. You may provide the layer which consists of a layer which consists of a vapor deposition film of a metal, a vapor deposition film of an inorganic oxide, and a gas barrier coating film.

  As the paper layer 66, any paper can be used depending on the desired rigidity, for example, high-quality paper, imitation paper, art paper, coated paper, pure white roll paper, kraft paper, and a label with improved water resistance. Known paper such as paper, cup base paper, card paper, ivory paper, paperboard such as manila ball, milk carton base paper, cup base paper, synthetic paper, clay coat paper can be used.

  Further, before laminating the second sealant layer 21B on the paper layer 66, the surface of the paper layer 66 may be subjected to corona discharge treatment, frame treatment, or the like. By performing these treatments, the adhesive strength between the layers can be improved. The corona discharge treatment can be performed by using a known corona discharge treatment device and passing the paper substrate through the generated corona atmosphere. The frame processing can be performed by using a known frame processing device and burning the surface of the paper substrate with fire.

  The liquid paper container 60 can be manufactured by a conventionally known method using the above-described laminated film. For example, the liquid film container 60 can be made into a variety of shapes such as a gable top type and a brick type by boxing the laminated film. Can be manufactured.

  The liquid paper container 60 is a wrapping paper for general liquids such as alcohol such as sake, shochu and wine, milk drinks such as milk, soft drinks such as orange juice and tea, chemical products such as car wax, shampoo and detergent. It can be suitably used as a container.

[Paper cup]
The case where a paper cup is formed using the laminated | multilayer film to which the polyester film by this invention is applied is demonstrated. FIG. 14 is a perspective view in which a part of the paper cup is cut out. As shown in FIG. 14, the paper cup 70 has a flange portion 71 at the top and is provided at a cylindrical barrel portion 72 that gradually increases in diameter toward the opening, and a lower end (one end) of the barrel portion 72. And a bottom portion 73. The body portion 72 is provided with a flange portion 71 whose upper end is rounded outward. In addition, the paper cup 70 is sealed by sticking a cover material along the flange portion 71 of the trunk portion 72 after storing the contents. The lid member preferably has a gas barrier property, and a conventionally known lid member having a gas barrier property can also be used.

  The trunk | drum 72 can be formed using the laminated | multilayer film to which the polyester film by this invention is applied. FIG. 15 is a partial cross-sectional view showing an example of a configuration of a laminated film used in the body portion of the paper cup. As shown in FIG. 15, the laminated film 20 </ b> G forming the body portion 72 includes a sealant layer 21, a polyester film 10, an adhesive resin layer 55, a paper base material (paper layer) 66, and a printing layer 34. The polyester film 10, the adhesive resin layer 55, the paper layer 66, and the printing layer 34 can be configured by laminating in this order from the inner surface side to the outer surface side of the body portion 72. In addition, the laminated film 20G may be provided with the barrier layer between any of the layers constituting the laminated film 20G such as between the polyester film 10 and the adhesive resin layer 55. You may provide the layer which consists of a layer which consists of a vapor deposition film of a metal, a vapor deposition film of an inorganic oxide, and a gas barrier coating film.

  As the laminated film 20G forming the body portion 72, for example, a laminated film obtained by laminating low-density polyethylene as the sealant layer 21, the polyester film 10, the low-density polyethylene as the adhesive resin layer 55, and the support 33 in this order is used. it can. As for the bottom portion 73, similarly to the body portion 72, a laminated film in which low density polyethylene, the polyester film 10 as the sealant layer 21, low density polyethylene as the adhesive resin layer 55, and a paper layer 66 are laminated in this order is used. Can do.

  In the present embodiment, the laminated film 20G is provided with the printing layer 34 on the outer surface side of the paper layer 66, but the present invention is not limited to this. Further, a sealant layer 21 may be provided between the two.

  An example of the outline of the manufacturing method of a paper cup is shown in FIG. As shown in FIG. 16, the printed layer 34 of the body blank 72 ′ cut out in a fan shape from the laminated film shown in FIG. 15 and given a predetermined contour is positioned outside, and the printed layer 34 is positioned inside. Then, they are rounded into a cylindrical shape and bonded together by heat sealing in a state where both end portions 72a ′ are overlapped. As a result, a body pasting portion 75 is formed in the body portion 2.

  Further, a bottom blank 73 ′ is cut out circularly from a cup base paper (not shown), and the outer peripheral edge of the bottom blank 73 ′ is bent downward to form a bent portion 73 a ′. The bottom blank 73 'may be cut out from the laminated film 20G.

  Next, a molded bottom blank 73 ′ is disposed below the barrel blank 72 ′ processed into a cylindrical shape. And the lower end part of trunk | drum blank 72 'is bent so that the bending part 73a' of bottom blank 73 'may be wrapped in the lower end part of trunk | drum blank 72'. While maintaining this state, the portion where the bent portion 73a ′ of the bottom blank 73 ′ and the lower end of the trunk blank 72 ′ overlap is melted with hot air, and these are integrated by applying a predetermined pressure to the portion. To do. Then, the paper cup 70 is completed by forming the flange part 71 in the upper end part of the trunk | drum 72. FIG. The laminated film 20G forming the body 72 is laminated in the order of the sealant layer 21, the polyester film 10, the adhesive resin layer 55, the paper layer 66, and the printing layer 34 from the inner surface side to the outer surface side of the paper cup 70. Layer 34 is configured to be located on the outermost side.

  The paper cup 70 can be suitably used as a container for storing snacks, instant foods that are poured into hot water, foods heated in a microwave oven, other instant foods, heated beverages, beverages heated in a microwave oven, and the like. .

  In this embodiment, although the case where the trunk | drum 72 was formed using laminated | multilayer film 20G was demonstrated, it is not limited to this, Only the bottom part 73 or the trunk | drum 72 and the bottom 73 forms laminated | multilayer film 20G. It may be formed using.

DESCRIPTION OF SYMBOLS 10 Polyester film 20A-20G Laminated film 21 Sealant layer 21A 1st sealant layer 21B 2nd sealant layer 30 Standing pouch 33 Support body 34 Print layer 41 Pillow bag 42 Three-way seal bag 43 Four-way seal bag 50 Tube container 54 Adhesion Resin layer 60 Liquid paper container 70 Paper cup

Claims (4)

A laminated film for food packaging having a single layer polyester film and a sealant layer provided on one side of the polyester film ,
The polyester film is located on the outermost surface side of the laminated film for food packaging,
The polyester film includes a biomass-derived ethylene glycol as a diol unit, and a virgin biomass polyester including a dicarboxylic acid derived from fossil fuel as a dicarboxylic acid unit;
A mechanically recycled polyester obtained by mechanically recycling a PET bottle containing a fossil fuel-derived diol and / or biomass-derived ethylene glycol as a diol unit and a fossil fuel-derived dicarboxylic acid as a dicarboxylic acid unit. A laminated film for food packaging . The laminated film for food packaging according to claim 1, wherein the total thickness of the polyester film is 5 μm or more and less than 100 μm. The laminated film for food packaging according to claim 1 or 2, wherein the dicarboxylic acid is terephthalic acid. The package provided with the laminated | multilayer film for food packaging as described in any one of Claims 1-3.

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