Container Packaging

Abstract

The problem that this invention aims to solve is to provide a multilayer film that has good sealing strength for a wide range of substrates. [Solution] The present invention solves the above problems with a container packaging comprising a multilayer film having a seal layer (D) and a surface layer (A), or a laminate formed by laminating the multilayer film, and an adherend that adheres to the seal layer (D) of the multilayer film, wherein the surface material of the adherend is one or more selected from glass, aluminum, polyimide, nylon, acrylic acid ester, high-impact polystyrene (HIPS), polylactic acid, polyvinyl chloride, polycarbonate, and acrylonitrile-butadiene-styrene resin (ABS), and the seal layer (D) contains 65 to 95% by mass of crystalline polyester (d1).

Description

[Technical Field]

[0001] This invention relates to containers and packaging for food products, medical products, and the like. [Background technology]

[0002] Heat-sealable films are called sealant films and are used in a variety of containers and packaging. These include packaging bags made by overlapping films and bonding them together, and packaging containers that use film as a lid for rigid containers. While these films may be single-layer heat-sealable films, multi-layer films made by laminating multiple resins are widely used to better meet functional requirements such as easy opening. When sealing containers and packaging, sealant films are heat-sealed. However, depending on the type of film and the substrate, adhesion may not be possible, or the seal strength may be insufficient. Therefore, it is common practice to use different films depending on the substrate, requiring different films for different substrates. This has led to problems such as complicated inventory management and increased storage space and management costs for various films. In addition, in the manufacturing process, line changes are required to use different films, which can reduce work efficiency. Furthermore, there was a risk of adhesion failure due to incorrect film selection or improper use, which could negatively impact product quality and reliability. A film that could solve these problems and adhere with sufficient seal strength to a wide range of substrates had not yet been found. Furthermore, depending on the substrate, the seal strength sometimes decreased over time after sealing.

[0003] On the other hand, the applicant has invented a multilayer film for use as a lid material for polyester containers, in which the sealing layer (D) contains two or more of the following: crystalline polyester resin, amorphous polyester, and polyolefin resin (Patent Document 1). This easily peelable film is a multilayer film that has suitable heat sealability, easy opening, and film processability for polyester substrates, is less prone to blocking, and has high seal strength. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 7460036 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Through further investigation, the inventors discovered a multilayer film that adheres with sufficient sealing strength not only to polyester substrates but also to a wide range of substrates, thus completing the present invention.

[0006] In other words, the problem that the present invention aims to solve is to provide a multilayer film that has good sealing strength for a wide range of substrates. [Means for solving the problem]

[0007] The present invention solves the above problems with a container and packaging comprising a multilayer film having a seal layer (D) and a surface layer (A), and an adherend that adheres to the seal layer (D) of the multilayer film, wherein the surface material of the adherend is one or more selected from glass, aluminum, polyimide, nylon, acrylic acid ester, high-impact polystyrene (HIPS), polylactic acid, polyvinyl chloride, polycarbonate, and acrylonitrile-butadiene-styrene resin (ABS), and the seal layer (D) contains 65 to 95% by mass of crystalline polyester (d1).

[0008] In addition, the present invention relates to a laminate obtained by laminating a multilayer film having a seal layer (D) and a surface layer (A), and an adherend that adheres to the seal layer (D) of the multilayer film. The surface material of the adherend is selected from one or more of glass, aluminum, polyimide, nylon, acrylate, high impact polystyrene (HIPS), polylactic acid, polyvinyl chloride, polycarbonate, acrylonitrile-butadiene-styrene resin (ABS). The seal layer (D) contains 65 to 95% by mass of crystalline polyester (d1), and solves the above problems by means of container packaging.

Effect of the Invention

[0009] Since the multilayer film used in the present invention has suitable sealing properties for a wide range of adherends, it can be suitably applied as a container packaging for sealing the openings of various containers.

Embodiments for Carrying Out the Invention

[0010] (Multilayer Film) The multilayer film used in the present invention has a seal layer (D) and a surface layer (A), and the seal layer (D) contains 65 to 95% by mass of crystalline polyester (d1).

[0011] [Seal Layer (D)] The seal layer (D) of the multilayer film used in the present invention contains 65 to 95% by mass of crystalline polyester (d1). When the seal layer (D) contains 65% by mass or more of crystalline polyester (d1), good adhesive strength can be obtained for a wide range of adherends. Further, when the seal layer (D) contains 95% by mass or less of crystalline polyester (d1), defects such as wrinkles and blocking are unlikely to occur during film formation. Furthermore, it is preferable to further contain an amorphous polyester (d2) and / or a polyolefin resin (d3). More preferably, the amorphous polyester (d2) and / or the polyolefin resin (d3) is contained in an amount of 1 to 35% by mass. It is further preferable to contain 75 to 95% by mass of the crystalline polyester (d1) and 1 to 25% by mass of the polyolefin resin (d3). By using the seal layer (D), a multilayer film excellent in film-forming properties and having good adhesive strength to a wide range of adherends can be realized.

[0012] (Crystalline polyester (d1)) The above-mentioned crystalline polyester (d1) is a polyester resin produced by polycondensing a polyvalent carboxylic acid and a polyhydric alcohol and has crystallinity. Specifically, it has a crystal structure such as a lamellar crystal form or a spherulite form derived from a regular arrangement structure in a part of the resin skeleton. Such a crystalline polyester is characterized by having an endothermic peak derived from a single or plural crystal melting heats generated when the crystal structure melts due to heat in differential scanning calorimetry (DSC).

[0013] In the present invention, the melting point (Tm) of a polyester resin such as a crystalline polyester or an amorphous polyester is a value determined by a method conforming to Japanese Industrial Standard (JIS K7121), that is, a differential scanning calorimetry (DSC) method. Specifically, it is a value measured using a differential scanning calorimeter under the following conditions. Measuring device: DSC-7020 manufactured by Hitachi High-Tech Corporation Sample: Put about 5 mg of the sample in an aluminum container and cover it. Measuring conditions; 1. Heating from -50°C to 280°C (10°C / min) 2. Holding at 280 for 5 minutes 3. Cooling from 280°C to 25°C (10°C / min) 4. Holding at 25°C for 5 minutes 5. Heating from 25°C to 280°C (10°C / min) Analysis: In the measurement result of 5, the temperature at which the endothermic peak becomes maximum is taken as the melting point (Tm).

[0014] Examples of the polycarboxylic acids mentioned above include aromatic polycarboxylic acids such as phthalic acid, phthalic anhydride, terephthalic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, and trimellitic acid, as well as aliphatic polycarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, decanoic acid, undecanediic acid, dodecanediic acid, tridecanediic acid, tetradecanediic acid, heptadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, octadecanediic acid, dimer acid, and cyclohexanedicarboxylic acid. These can be used individually, or two or more can be used together. Furthermore, if necessary, monocarboxylic acids such as methaneic acid, ethaneic acid, propanoic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, heptadecanoic acid, and octadecanoic acid may be used as raw material components.

[0015] Examples of the above polyhydric alcohols include ethylene glycol, diethylene glycol, propylene glycol, 2-methyl-1,3-propanediol, 2,2-dimethyltrimethylene glycol, 1,4-butanediol, 1,5-pentanediol, 3-methylpentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,16-hexadecanediol, 1,18-octadecanediol, 1,20-icosanediol, 1,4-cyclohexanedimethanol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, neopentyl glycol, pentaethylene glycol, and trimethylolpropane.

[0016] The polycarboxylic acids and polyhydric alcohols mentioned above can be used in any combination. Specifically, examples include terephthalic acid / ethylene glycol copolymer, terephthalic acid / 1,4-butanediol copolymer, terephthalic acid / 1,4-butanediol / adipic acid copolymer, terephthalic acid / polytetramethylene ether glycol / 1,4-butanediol copolymer, terephthalic acid / isophthalic acid / 1,4-butanediol / polytetramethylene ether glycol copolymer, terephthalic acid / isophthalic acid / 1,4-butanediol copolymer, and so on.

[0017] The melting point of the above-mentioned crystalline polyester (d1) is preferably 100 to 200°C, and more preferably 110 to 180°C. Using a crystalline polyester with this melting point results in good extrusion moldability. Furthermore, the glass transition temperature of the crystalline polyester (d1) is preferably 40°C or lower, more preferably 0°C or lower, and more preferably -20°C or lower. Using a crystalline polyester (d1) with this glass transition temperature results in good heat sealability and easy opening. An example of such a crystalline polyester (d1) is a resin commercially available under the trade name "Byron" (Toyobo Co., Ltd.).

[0018] The glass transition temperature (Tg) of polyester resin is determined by a method conforming to the Japanese Industrial Standard (JIS K7121), i.e., by differential scanning calorimetry (DSC).

[0019] The above-mentioned seal layer (D) contains 65 to 95% by mass of crystalline polyester (d1). This allows for good seal strength even with adherends such as nylon and polyimide, which are difficult to adhere to with conventional sealant films. The content is preferably 70 to 95% by mass, more preferably 75 to 90% by mass, and even more preferably 80 to 90% by mass.

[0020] (Amorphous polyester (d2)) In the present invention, the sealing layer (D) preferably contains amorphous polyester (d2). The amorphous polyester (d2) is a polyester resin produced by polycondensation of a polycarboxylic acid and a polyhydric alcohol, and is a polyester that does not exhibit substantially crystalline properties. In particular, in the melting point measurement using differential scanning calorimeter as described above for crystalline polyester (d1), it is a polyester that does not have a clear melting peak temperature in the temperature range of 50°C to 280°C, and specifically means that the heat of fusion (ΔH) of crystallization in this temperature range is 1 J / g or less.

[0021] Examples of the polycarboxylic acids mentioned above include malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, hexahydrophthalic acid, 1,4-cyclohexanedicarboxylic acid, maleic acid, maleic anhydride, citraconic acid, dimethylmaleic acid, cyclopentene-1,2-dicarboxylic acid, 1-cyclohexene-1,2-dicarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, fumaric acid, mesaconic acid, itaconic acid, glutaconic acid, phthalic acid, phthalic anhydride, terephthalic acid, isophthalic acid, orthophthalic acid, 1,2,5-hexanetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, trimellitic acid, trimellitic anhydride, 1,2,5-benzenetricarboxylic acid, 2,5,7-naphthalentricarboxylic acid, pyromellitic acid, pyromellitic anhydride, etc. These may be used individually or in combination of two or more types. Furthermore, if necessary, monocarboxylic acids such as methaneic acid, ethaneic acid, propanoic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, heptadecanoic acid, and octadecanoic acid may be used as raw material components.

[0022] Examples of the above polyhydric alcohols include ethylene glycol, diethylene glycol, propylene glycol, 2-methyl-1,3-propanediol, 2,2-dimethyltrimethylene glycol, 1,4-butanediol, 1,5-pentanediol, 3-methylpentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,16-hexadecanediol, 1,18-octadecanediol, 1,20-icosanediol, 1,4-cyclohexanedimethanol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, neopentyl glycol, pentaethylene glycol, isosorbide, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, and trimethylolpropane. These can be used individually, or two or more can be used together.

[0023] The polycarboxylic acids and polyhydric alcohols mentioned above can be used in any combination. Specifically, examples include terephthalic acid / ethylene glycol / neopentyl glycol copolymer, terephthalic acid / ethylene glycol / 1,4-cyclohexanedimethanol / isosorbide copolymer, terephthalic acid / isophthalic acid / ethylene glycol copolymer, terephthalic acid / ethylene glycol / 1,4-cyclohexanedimethanol copolymer, and terephthalic acid / 1,4-cyclohexanedimethanol / 2,2,4,4-tetramethyl-1,3-cyclobutanediol copolymer.

[0024] The glass transition temperature of the amorphous polyester (d2) described above is preferably 45 to 130°C, and more preferably 60 to 120°C. By using amorphous polyester (d2) with this glass transition temperature, suitable film processability and heat resistance can be ensured. An example of such amorphous polyester (d2) is a resin commercially available under the trade name "ECOZEN" (SK Chemical Co., Ltd.).

[0025] In the present invention, the total content of the crystalline polyester (d1) and amorphous polyester (d2) in the seal layer (D) is preferably 70% by mass or more in order to obtain suitable heat sealability and heat resistance. Furthermore, it is more preferably 75% by mass or more, and even more preferably 80% by mass or more, in order to obtain a suitable film appearance. There is no particular upper limit to the content, but it is preferably 99% by mass or less, and more preferably 95% by mass or less. In addition, the content ratio of the crystalline polyester (d1) to the amorphous polyester (d2) is preferably 2:1 to 9:1.

[0026] The crystalline polyester (d1) and amorphous polyester (d2) in the sealing layer (D) of the present invention may be biodegradable polyesters. Examples of biodegradable polyesters include polylactic acid resins, poly(butylene succinate) (PBS), poly(butylene succinate / adipate) copolymers (PBSA), poly(3-hydroxybutyric acid), copolymers of 3-hydroxybutyric acid and 3-hydroxyvaleric acid, copolymers of 3-hydroxybutyric acid and 4-hydroxybutyric acid, and other polyhydroxyalkanoates, aliphatic polyester compounds such as polyglycolic acid, polycaprolactone, ring-opening polymers such as β-propiolactone and γ-valerolactone, adipic acid and 1.4 Examples of biodegradable resins include: copolyesters of butanediol and terephthalic acid (polybutylene adipate terephthalate), polyesters made of succinic acid and ethylene glycol (polyethylene succinate), polyesters made of aliphatic dibasic acids and aliphatic diols, copolymers of aromatic polyesters and aliphatic polyesters, copolymers of aliphatic polyesters and polyamides, polyvinyl alcohol, pullulan, chitosan, curdlan, starch-based green plastics, esterified starch, cellulose, and cellulose acetate. These biodegradable polyesters are also treated as crystalline polyesters if they have endothermic peaks originating from one or more heats of fusion generated when the crystalline structure melts due to heat in differential scanning calorimetry (DSC), and amorphous polyesters if they do not have a clear melting peak temperature in the temperature range of 50°C to 280°C in differential scanning calorimeter melting point measurements, specifically if the heat of fusion (ΔH) is 1 J / g or less in this temperature range.

[0027] (Polyolefin resin (d3)) The sealing layer (D) in the present invention may also preferably contain a polyolefin resin (d3). The polyolefin resin (d3) is uniformly dispersed in the poorly miscible crystalline polyester (d1) and amorphous polyester (d2), thereby improving blocking resistance and peel appearance. As the polyolefin resin (d3) mentioned above, ethylene resins and propylene resins can be preferably used. As ethylene resins, polyethylene resins such as very low-density polyethylene (VLDPE), linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), linear medium-density polyethylene (LMDPE), medium-density polyethylene (MDPE), and high-density polyethylene (HDPE) can be used. As propylene resins, examples include propylene homopolymers, propylene-α-olefin random copolymers such as propylene-ethylenebutene-1 copolymer, and propylene block copolymers such as propylene-α-olefin block copolymer. Among these, propylene block copolymers are preferred.

[0028] As the propylene block copolymer mentioned above, a resin containing propylene and other α-olefins can be used. Examples of α-olefins include ethylene, 1-butene, 1-hexene, 4-methyl·1-pentene, and 1-octene, among which ethylene is preferred due to its excellent heat resistance and impact resistance. The propylene-ethylene block copolymer is not particularly limited, but for example, it can be obtained by polymerizing a polymer block mainly composed of propylene in the first step, and polymerizing an ethylene-propylene copolymer block in the second step.

[0029] The above-mentioned propylene block copolymer preferably has a cloudiness of 30% or more, and more preferably 40% or more, when molded to a thickness of 60 μm using a T-die film deposition method with a cooling roll at 40°C. Using a resin with this cloudiness level provides suitable blocking resistance and film processability.

[0030] The melt flow rate (MFR) of the above-mentioned propylene block copolymer is preferably 0.5 to 10 g / 10 min (230°C, 21.18 N), and more preferably 2 to 5 g / 10 min, because it facilitates molding and easily provides suitable openability.

[0031] The melting point of the above-mentioned propylene block copolymer is preferably 150°C or higher, and more preferably 160°C or higher, because it facilitates molding and ensures excellent heat resistance.

[0032] In the present invention, when the seal layer (D) contains the polyolefin resin (d3), it is preferable that its content be 1 to 30% by mass of the resin components contained in the seal layer (D). In particular, when the seal layer (D) contains 70 to 95% by mass of crystalline polyester (d1), it is preferable that it contains 1 to 30% by mass of the polyolefin resin (d3), and more preferably that it contains 1 to 30% by mass of propylene block copolymer. That is, it is preferable that the seal layer (D) contains 70 to 95% by mass of crystalline polyester (d1) and 1 to 30% by mass of the polyolefin resin (d3), and more preferably that it contains 70 to 95% by mass of crystalline polyester (d1) and 1 to 30% by mass of propylene block copolymer. By using this sealing layer (D), suitable blocking resistance and film processability can be obtained.

[0033] In the present invention, it is preferable to use two or more of the above-mentioned crystalline polyester (d1), amorphous polyester (d2), and polyolefin resin (d3) as the resin used in the sealing layer (D). It is also preferable to use only these resins, but various other resins used in packaging films may also be used. Examples of other resins include thermoplastic elastomers such as polyethylene elastomers, polypropylene elastomers, and butene elastomers; ethylene copolymers such as ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate (EMA) copolymer, ethylene-ethyl acrylate-maleic anhydride copolymer (E-EA-MAH), ethylene-acrylic acid copolymer (EAA), and ethylene-methacrylic acid copolymer (EMAA); and further, norbornene polymers such as ionomers of ethylene-acrylic acid copolymers, ionomers of ethylene-methacrylic acid copolymers, ring-opening polymers of norbornene monomers (COP), norbornene copolymers obtained by copolymerizing norbornene monomers with olefins such as ethylene (COC), and their hydrogenated products, as well as cyclic polyolefin resins such as vinyl alicyclic hydrocarbon polymers and cyclic conjugated diene polymers.

[0034] In the present invention, when a resin other than the crystalline polyester (d1), amorphous polyester (d2), and polyolefin resin (d3) is used as the resin component for the seal layer (D), it is preferable that its content be 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less of the total resin component in the seal layer (D).

[0035] In the seal layer (D) of the present invention, components such as antistatic agents, heat stabilizers, nucleating agents, antioxidants, antistatic agents, lubricants, antifogging agents, antiblocking agents, mold release agents, ultraviolet absorbers, colorants, and biodegradability-granting agents may be added to the seal layer (D) within a range that does not impair the objective of the present invention. When using these additives, they are preferably used in amounts of 10 parts by mass or less, more preferably about 0.01 to 8 parts by mass, per 100 parts by mass of the resin component used in the seal layer (D). The additives are not particularly limited, and commercially available ones can be used.

[0036] When using the above-mentioned additives, it is preferable to keep the filler content, particularly the inorganic filler content, at 300 ppm or less, more preferably at 200 ppm or less, even more preferably at 100 ppm or less, and especially preferably substantially absent, in order to ensure suitable heat sealability.

[0037] In the present invention, the thickness ratio of the sealing layer (D) to the total thickness of the multilayer film is preferably in the range of 5 to 30%, and more preferably in the range of 10 to 25%, in order to obtain easy opening and film processability.

[0038] [Surface layer (A)] The surface layer (A) of the multilayer film used in the present invention preferably contains two or more of the following: crystalline polyester (a1), amorphous polyester (a2), and polyolefin resin (a3), and more preferably contains crystalline polyester (a1), amorphous polyester (a2), and polyolefin resin (a3). Using this surface layer (A) results in good blocking resistance and film processability.

[0039] The crystalline polyester (a1) used in the surface layer (A) can be the same as the crystalline polyester (d1) used in the sealing layer (D), and the preferred material is also the same.

[0040] The amorphous polyester (a2) used in the surface layer (A) can be the same as the amorphous polyester (d2) used in the sealing layer (D), and the same is also preferred.

[0041] The polyolefin resin (a3) ​​used in the surface layer (A) can be the same as the polyolefin resin (d3) used in the sealing layer (D), and the same is also preferred. In particular, it is preferable to use a propylene block copolymer as the polyolefin resin (a3). By using this polyolefin resin (a3), the surface smoothness of the film is reduced, which improves blocking resistance and also prevents the film surface from adhering to the winding roll.

[0042] The amount of the polyolefin resin (a3) ​​in the resin component contained in the surface layer (A) is preferably 1 to 30% by mass, more preferably 1 to 25% by mass, and even more preferably 3 to 20% by mass, as this facilitates film processability and transparency.

[0043] In the surface layer (A) described above, it is preferable to use two or more of the crystalline polyester (a1), amorphous polyester (a2), and polyolefin resin (a3) ​​described above as the resin to be used, and it is also preferable to use only these resins, but other resins used for packaging films may also be used. The other resins can be the same as the various resins exemplified in the seal layer (D) described above. When using these other resins, it is preferable that their content be 20% by mass or less of the resin components contained in the surface layer (A), more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0044] The surface layer (A) may also be appropriately combined with various additives similar to those used in the sealing layer (D). When using these additives, they are preferably used in amounts of 2 parts by mass or less, and more preferably 0.01 to 1 part by mass, per 100 parts by mass of the resin component used in the surface layer (A).

[0045] The filler content, particularly the inorganic filler content, is preferably 300 ppm or less, more preferably 200 ppm or less, even more preferably 100 ppm or less, and especially preferably substantially absent, similar to the seal layer (D).

[0046] The thickness ratio of the surface layer (A) to the total thickness of the multilayer film is preferably in the range of 10 to 95%, and more preferably in the range of 20 to 90%, as this facilitates obtaining suitable film processability.

[0047] (Middle layer (C)) In the multilayer film used in the present invention, it is also preferable to have an intermediate layer (C) that is directly laminated with the seal layer (D) between the surface layer (A) and the seal layer (D). If the intermediate layer (C) is provided, the intermediate layer contains crystalline polyester (c1) and / or amorphous polyester (c2), and the difference between the sum of the mass ratio of the crystalline polyester (d1) in the resin component contained in the seal layer (D) and the mass ratio of the crystalline polyester (c1) in the resin component contained in the intermediate layer (C) and the sum of the mass ratio of the amorphous polyester (d2) in the resin component contained in the seal layer (D) and the mass ratio of the amorphous polyester (c2) in the resin component contained in the intermediate layer (C) is preferably within 60% by mass, more preferably within 30% by mass, and even more preferably within 25% by mass. In other words, it is preferable to adjust the composition ratio of crystalline polyester (c1) and amorphous polyester (c2) in the intermediate layer (C) according to the composition ratio of crystalline polyester (d1) and amorphous polyester (d2) in the sealing layer (D). By providing such an intermediate layer (C), it becomes easier to ensure particularly stable peelability, and therefore it can be suitably used in applications where easy peelability is required.

[0048] The crystalline polyester (c1) and amorphous polyester (c2) described above can be the same as the crystalline polyester (d1) and amorphous polyester (d2) disclosed in the sealing layer (D), and the preferred materials are also the same.

[0049] The total content of the crystalline polyester (c1) and / or amorphous polyester (c2) in the resin component contained in the intermediate layer (C) is preferably 70 to 100% by mass, and more preferably 80 to 100% by mass. By setting the total content of the crystalline polyester (c1) and / or amorphous polyester (c2) within this range, stable easy-open properties can be easily ensured, and transparency is also good.

[0050] The intermediate layer (C) may further contain a polyolefin resin (c3). The same polyolefin resin (c3) as that used in the sealing layer (D) can be used, and the same preferred resins are also used. In particular, it is preferable to use a propylene block copolymer as the polyolefin resin (c3). The content of the polyolefin resin (c3) is preferably less than 30% by mass of the resin components contained in the intermediate layer (C), and more preferably less than 20% by mass.

[0051] In the intermediate layer (C) described above, it is preferable to use only the crystalline polyester (c1) and amorphous polyester (c2) as resin components, but a polyolefin resin (c3) may also be used, or various other resins used in packaging films may be used. As such other resins, the various resins exemplified in the sealing layer (D) described above can be used in the same way. When using these other resins, it is preferable that their content be less than 20% by mass of the resin components contained in the intermediate layer (C), more preferably less than 10% by mass, and even more preferably less than 5% by mass.

[0052] In the intermediate layer (C) described above, various additives similar to those used in the sealing layer (D) may be used in appropriate combination. When using these additives, they are preferably used in amounts of 2 parts by mass or less, and more preferably 0.01 to 1 part by mass, per 100 parts by mass of the resin component used in the intermediate layer (C).

[0053] When the above-mentioned intermediate layer (C) is provided, the thickness ratio of the intermediate layer (C) to the total thickness of the multilayer film is preferably in the range of 5 to 80%, and more preferably in the range of 10 to 70%.

[0054] (Middle layer (B)) The multilayer film used in the present invention may include an intermediate layer (B) in addition to the surface layer (A), intermediate layer (C), and sealing layer (D) described above. The intermediate layer (B) is located between the surface layer (A) and the intermediate layer (C). The intermediate layer (B) may consist of two or more layers.

[0055] The intermediate layer (B) preferably contains crystalline polyester (b1) and / or amorphous polyester (b2) as resin components. Furthermore, the total mass ratio of crystalline polyester (b1) and amorphous polyester (b2) in the resin components contained in the intermediate layer (B) is preferably 80% by mass or more, and more preferably 90% by mass or more. Moreover, from a cost standpoint, it is preferable that the mass ratio of crystalline polyester (b1) in the resin components contained in the intermediate layer (B) is less than that of amorphous polyester (b2). Furthermore, when the intermediate layer (B) is composed of multiple layers, the effects of the present invention can be suitably realized by having each layer contain crystalline polyester (b1) and amorphous polyester (b2), with the content of crystalline polyester (b1) in the resin component contained in the intermediate layer (B) being 0 to 50% by mass and the content of amorphous polyester (b2) being 50 to 100% by mass. Note that when the intermediate layer (B) is composed of multiple layers, each layer may have the same formulation or different formulations, as long as it remains within the specified formulation range.

[0056] The thickness ratio of the above-mentioned intermediate layer (B) is preferably 20-90%, and more preferably 40-70%. When the intermediate layer (B) consists of multiple layers, the total thickness of the intermediate layer (B) is preferably 20-90% of the total thickness of the multilayer film, and more preferably 40-70%.

[0057] [Multilayer film] The multilayer film used in the present invention is a film having the above-mentioned sealing layer (D) and surface layer (A). Furthermore, it is preferable that the mass ratio of crystalline polyester resin to the total resin constituting the multilayer film is 10% by mass or more, the mass ratio of amorphous polyester resin to the total resin constituting the multilayer film is 20% by mass or more, and the mass ratio of polyolefin resin to the total resin constituting the multilayer film is 1% by mass or more. The crystalline polyester resin includes crystalline polyester (a1), crystalline polyester (b1), crystalline polyester (c1), crystalline polyester (d1), and other crystalline polyester resins; the amorphous polyester resin includes amorphous polyester (a2), amorphous polyester (b2), amorphous polyester (c2), amorphous polyester (d2), and other amorphous polyester resins; and the polyolefin resin includes polyolefin resin (a3), polyolefin resin (b3), polyolefin resin (c3), polyolefin resin (d3), and other polyolefin resins.

[0058] The mass ratio of the crystalline polyester resin to the total resin constituting the multilayer film used in the present invention is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 20 to 50% by mass or more, and particularly preferably 20 to 40% by mass. When the mass ratio of the crystalline polyester resin is within this range, it becomes easier to achieve both high transparency and a good peel appearance. Furthermore, the mass ratio of the amorphous polyester resin to the entire multilayer film is preferably 20% by mass or more, more preferably 50% by mass or more, and even more preferably 60-80% by mass. When the mass ratio of the amorphous polyester resin is within this range, the rigidity is good, and the physical properties of the multilayer film can be easily adjusted. Furthermore, the mass ratio of the polyolefin resin to the total resin constituting the multilayer film is preferably 1% by mass or more, more preferably 1 to 20% by mass, and even more preferably 2 to 10% by mass. When the mass ratio of the polyolefin resin is within this range, a multilayer film with excellent blocking resistance and a good peel appearance can be obtained.

[0059] In order to prevent blocking, the multilayer film used in the present invention preferably contains the polyolefin resin in either the sealing layer (D) or the surface layer (A), and more preferably contains the polyolefin resin in both the sealing layer (D) and the surface layer (A).

[0060] Each layer of the multilayer film used in the present invention (surface layer (A), intermediate layer (B), intermediate layer (C), sealing layer (D), etc.) may contain, as needed, components such as antistatic agents, heat stabilizers, nucleating agents, antioxidants, antistatic agents, lubricants, antifogging agents, antiblocking agents, mold release agents, ultraviolet absorbers, colorants, and biodegradability-granting agents, to the extent that they do not impair the objectives of the present invention.

[0061] The minimum layer configuration of the multilayer film used in the present invention is a surface layer (A) / seal layer (D). If an intermediate layer (C) is provided, the multilayer film has a layer configuration of surface layer (A) / intermediate layer (C) / seal layer (D). If an intermediate layer (B) is provided, the multilayer film has a layer configuration of surface layer (A) / intermediate layer (B) / intermediate layer (C) / seal layer (D). Furthermore, if the intermediate layer (B) consists of multiple layers, the layer configuration may be, for example, surface layer (A) / intermediate layer (B1) / intermediate layer (B2) / intermediate layer (C) / seal layer (D). Other layers may also be included. The multilayer film used in this invention, with its configuration, has suitable heat sealability and easy peelability, is less prone to blocking during film formation, and has suitable heat resistance that ensures high seal strength even after high-temperature treatment.

[0062] The multilayer film used in the present invention more preferably includes the above-mentioned intermediate layer (C) and / or intermediate layer (B). By including the intermediate layer (C) and / or intermediate layer (B), it becomes easier to adjust the amount of polyolefin resin added to the multilayer film used in the present invention, and transparency can be improved.

[0063] In the multilayer film used in the present invention, it is preferable that the mass ratio of polyester resin to the total resin constituting the multilayer film is 70% by mass or more. The polyester resin includes the crystalline polyester resin, the amorphous polyester resin, and other polyesters. Furthermore, it is more preferable that the mass ratio is 80% by mass or more, and even more preferable that it is 90% by mass or more. By setting the mass ratio to 70% by mass or more, the recyclability of the film is improved. Furthermore, when it is 90% by mass or more, it becomes easier to achieve monomaterialization of the packaging material, and the recyclability is further improved.

[0064] The multilayer film used in this invention preferably has a thickness of 5 to 100 μm, more preferably 10 to 80 μm, and even more preferably 20 to 60 μm. A film thickness within this range makes it easier to obtain suitable heat sealability, heat resistance, film processability, and other properties.

[0065] Furthermore, the thickness of each layer is not particularly limited, but for example, the thickness of the surface layer (A) is preferably 1 to 40 μm, more preferably 1 to 30 μm, and even more preferably 3 to 30 μm. The thickness of the sealing layer (D) is preferably 1 to 30 μm, more preferably 2 to 20 μm, and even more preferably 2.5 to 10 μm. If an intermediate layer (C) is provided, its thickness is preferably 1 to 30 μm, more preferably 2 to 20 μm, and even more preferably 3 to 10 μm. If an intermediate layer (B) is provided, its thickness is preferably 1 to 60 μm, more preferably 2 to 50 μm, and even more preferably 3 to 40 μm.

[0066] Furthermore, when the intermediate layer (B) consists of multiple layers, for example, a surface layer (A) / intermediate layer (B1) / intermediate layer (B2) / intermediate layer (C) / seal layer (D), it is preferable that the total thickness of intermediate layer (B1) and intermediate layer (B2) is within the preferred thickness range of the intermediate layer (B).

[0067] The sealing method is not particularly limited, and methods such as ultrasonic sealing may be used, but heat sealing is particularly preferred.

[0068] The method for manufacturing the multilayer film used in the present invention is not particularly limited, but for example, the resin or resin mixture used for the surface layer (A) and the sealing layer (D), the resin or resin mixture used for the intermediate layer (C) if an intermediate layer (C) is provided, and the resin or resin mixture used for the intermediate layer (B) if an intermediate layer (B) is provided are each heated and melted in separate extruders, and then laminated in the molten state in the order of (A) / (D), (A) / (C) / (D), or (A) / (B) / (C) / (D) using methods such as the co-extrusion multilayer die method or the feed block method, and then formed into a film by inflation or the T-die chill roll method. This co-extrusion method is preferred because it allows for relatively free adjustment of the thickness ratio of each layer, and a multilayer film with excellent hygiene and cost performance can be obtained.

[0069] Since the multilayer film used in the present invention is obtained as a substantially unstretched multilayer film by the above manufacturing method, secondary molding such as deep drawing by vacuum forming is also possible.

[0070] Furthermore, it is preferable to apply a surface treatment to the surface layer (A) in order to improve adhesion to printing inks and lamination suitability when used as a sealant film for lamination. Examples of such surface treatments include surface oxidation treatments such as corona treatment, plasma treatment, chromic acid treatment, flame treatment, hot air treatment, ozone / ultraviolet treatment, or surface roughening treatments such as sandblasting, but corona treatment is preferred.

[0071] (Laminated structure) The multilayer film used in the present invention can also be laminated by bonding it to a substrate, coating it, or the like to form a laminate having the multilayer film. The structure of the laminate used in the present invention is as follows: (1) Substrate / Adhesive layer / Multilayer film used in the present invention (2) Substrate / Adhesive layer / Printing layer / Multilayer film used in the present invention (3) Substrate / Adhesive layer / Second substrate / Printing layer / Adhesive layer / Multilayer film used in the present invention (4) Substrate / Adhesive layer / First printing layer / Second printing layer / Multilayer film used in the present invention (5) Substrate / Adhesive layer / Barrier layer / Adhesive layer / Multilayer film used in the present invention (6) Substrate / Adhesive layer / Barrier layer / Printing layer / Adhesive layer / Multilayer film used in the present invention (7) Substrate / Printing layer / Adhesive layer / Multilayer film used in the present invention (8) Substrate / First printing layer / Second printing layer / Adhesive layer / Multilayer film used in the present invention (9) Substrate / Printing layer / Adhesive layer / Barrier layer / Adhesive layer / Multilayer film used in the present invention (10) Substrate / Adhesive layer / Barrier layer / Adhesive layer / Second substrate / Adhesive layer / Multilayer film used in the present invention (11) Substrate / Printing layer / Adhesive layer / Barrier layer / Adhesive layer / Second substrate / Adhesive layer / Multilayer film used in the present invention Examples include, but are not limited to, additional base materials may be included. When multiple adhesive layers are included, each layer may have the same composition or be different, and the thickness of the multiple adhesive layers may be the same or different; there are no particular limitations. The second and additional substrates may be unstretched resin films, stretched resin films, metal-deposited films such as unstretched metal-deposited films or stretched metal-deposited films, or transparent metal-deposited films, and are not particularly limited. Furthermore, the multiple adhesive layers may have the same composition or different compositions. Furthermore, to improve the adhesive strength of the adhesive layer, an anchor coat layer may be sandwiched between the layers. Furthermore, the substrate may have a coating layer that provides functions such as mold release and antistatic properties.

[0072] (base material) The above-mentioned substrates are not particularly limited and include polyethylene terephthalate (PET) film, polybutylene terephthalate (PBT) film, polystyrene film, polyamide film, nylon film, polyacrylonitrile film, polyolefin films such as polyethylene film (OPE: biaxially oriented polyethylene film, LLDPE: low-density polyethylene film, HDPE: high-density polyethylene film) and polypropylene film (CPP: unoriented polypropylene film, OPP: biaxially oriented polypropylene film), polyvinyl alcohol film, ethylene-vinyl alcohol copolymer film, cellophane, and the like. In particular, since the multilayer film used in the present invention can be adhered to nylon, using nylon as the base material is preferable because it allows sealing between the surface (nylon) and the back surface (the sealing layer (D) of the multilayer film used in the present invention) of the laminate.

[0073] Furthermore, films can be used that have inorganic vapor-deposited layers such as film silica or metal oxides like alumina. Specific examples include OPE films, OPP films, PET films, PBT films, and nylon films having a silica vapor-deposited layer, and OPE films, OPP films, PET films, PBT films, and nylon films having an alumina vapor-deposited layer.

[0074] When considering monomaterial packaging, a film made of a thermoplastic resin mainly composed of polyester resin can be used as the base material. Specific examples of polyester resins include polyethylene terephthalate (PET) and polybutylene terephthalate (PBT). The multilayer film used in this invention can be made of polyester monomaterial film by using the above-mentioned polyester resin as the base material, which is preferable for reducing environmental impact.

[0075] Furthermore, it is also preferable to use a film made from a material containing biomass-derived components as the film substrate. Biomass films are sold by various companies, and for example, films and sheets listed in the biomass certified product list provided by the Japan Organic Resources Association can be used.

[0076] A well-known example of a film made from biomass-derived ethylene glycol is derived from ethanol produced from biomass (biomass ethanol). For example, biomass-derived ethylene glycol can be obtained by conventionally known methods, such as a method that produces ethylene glycol via ethylene oxide from biomass ethanol. Alternatively, commercially available biomass ethylene glycol may be used; for example, the biomass ethylene glycol commercially available from India Glycol can be suitably used.

[0077] Alternatively, products using biomass raw materials, distinguished by their biomass plasticity as defined by ISO 16620 or ASTM D6866, are also available. In the atmosphere, 10 12 Radioactive carbon-14C is present at a rate of one molecule per unit, and this rate does not change even in atmospheric carbon dioxide. Therefore, this rate remains unchanged even in plants that fix carbon dioxide through photosynthesis. For this reason, plant-derived resins contain radioactive carbon-14C. In contrast, fossil fuel-derived resins contain almost no radioactive carbon-14C. By measuring the concentration of radioactive carbon-14C in the resin using an accelerator mass spectrometer, the proportion of plant-derived resin in the resin, i.e., the biomass plastic content, can be determined. Examples of plant-derived low-density polyethylene that are biomass plastics with a biomass plastic content of 80% or more, preferably 90% or more, as defined by ISO 16620 or ASTM D6866, include Braskem's product names "SBC818," "SPB608," "SBF0323HC," "STN7006," "SEB853," and "SPB681," and films using these as raw materials can be suitably used.

[0078] For example, as an alternative to conventional polyolefin films using petroleum-based raw materials, biomass polyolefin films such as biomass polyethylene films and biomass polyethylene-polypropylene films, which contain ethylene resins made from biomass-derived ethylene glycol, are also known. The ethylene-based resin is not particularly limited except for the use of ethylene glycol derived from the biomass mentioned above as part of the raw materials. Examples include ethylene homopolymers, copolymers of ethylene and α-olefins with ethylene as the main component (ethylene-α-olefin copolymers containing 90% by mass or more of ethylene units), and these can be used individually or in combination of two or more. The α-olefin constituting the copolymer of ethylene and α-olefin is not particularly limited, and examples include α-olefins having 4 to 8 carbon atoms, such as 1-butene, 4-methyl-1-pentene, 1-hexene, and 1-octene. Known polyethylene resins such as low-density polyethylene resin, medium-density polyethylene resin, and linear low-density polyethylene resin can be used. Among these, linear low-density polyethylene resin (LLDPE) (a copolymer of ethylene and 1-hexene, or a copolymer of ethylene and 1-octene) is preferred from the viewpoint of making it even less likely for damage such as punctures or tears to occur when the films rub against each other, and has a density of 0.910 to 0.925 g / cm³. 3 A linear low-density polyethylene resin is more preferable.

[0079] The biomass film may be a laminate formed by stacking multiple biomass films, or it may be a laminate formed by combining a conventional petroleum-based film with a biomass film.

[0080] The above-mentioned substrate may be subjected to some kind of surface treatment, such as physical treatments like corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, or flame treatment, or chemical treatments such as oxidation treatment using chemicals, or other treatments.

[0081] The above-mentioned substrate can be manufactured using conventionally known film formation methods such as extrusion, casting, T-die, cutting, and inflation methods. It may be an unstretched film, or, from the viewpoint of film strength, dimensional stability, and heat resistance, it may be stretched in one or two axes using a tenter method, tubular method, etc.

[0082] The above-mentioned base material may contain additives as needed. Specifically, to improve or modify properties such as processability, heat resistance, weather resistance, mechanical properties, dimensional stability, oxidation resistance, slipperiness, release properties, flame retardancy, mold resistance, electrical properties, and strength, plastic compounding agents such as elastomers, lubricants, crosslinking agents, antioxidants, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, and pigments, as well as additives such as compatibilizers and biodegradability-granting agents, may be added. The amount of additives added should be adjusted within a range that does not affect other properties or recyclability.

[0083] The film thickness of the above-mentioned substrate is not particularly limited and can be appropriately selected within the range of 0.1 to 300 μm from the viewpoint of moldability and transparency. Preferably, it is in the range of 0.3 to 100 μm. If the film thickness of the substrate is 0.1 to 300 μm, good strength and processing stability can be obtained.

[0084] From a recycling perspective, it is preferable to keep the layer structure as simple as possible, but from the perspective of the distribution of the container and packaging, printing to display the contents of the container and packaging, as well as product descriptions and names, may be included.

[0085] (adhesive layer) The adhesive layer has the function of bonding any two layers constituting the laminate, for example, a base material layer and a second base material layer. Any adhesive usable in a general-purpose lamination method can be used for this adhesive layer. Examples of lamination methods include dry lamination, wet lamination, non-solvent lamination, extrusion lamination, sand lamination, and heat lamination. After the adhesive hardens or dries, it forms the adhesive layer.

[0086] As adhesives used in the above dry lamination, for example, one-component or two-component curing or non-curing type adhesives such as vinyl-based, (meth)acrylic-based, polyamide-based, polyester-based, polyether-based, polyurethane-based, epoxy-based, rubber-based, and others, can be used, including solvent-based, water-based, or emulsion-type adhesives. As a two-component curing type adhesive, a two-component curing adhesive consisting of a polyol and an isocyanate compound can be used. Among the above adhesives, a two-component curing adhesive comprising a polyol composition and a polyisocyanate composition is preferred.

[0087] (Two-part curing adhesive) The above two-component curing adhesive preferably contains a polyisocyanate composition (X) and a polyol composition (Y).

[0088] (Polyisocyanate composition (X)) The above polyisocyanate composition (X) is not particularly limited and can be any polyisocyanate composition (X) used in the adhesive technology field, for example, a urethane prepolymer, a mixture of a urethane prepolymer and an isocyanate compound, and an isocyanate compound can be used.

[0089] The above two-component curing adhesives can also be commercially available products, such as DIC Graphics Co., Ltd.'s DIC Dry LX-500 / KW-75, DIC Dry LX-520 / KO40, DIC Dry LX-703VL / KR-90, DIC Dry LX-732 / KVM-90, DIC Dry LX-906 / KO55, DIC Dry LX-963 / KO-40, DIC Dry LX-901 / KW-75, etc., and Toyo Ink Co., Ltd.'s TM-250HV / CAT-RT86, TM-595 / CAT-56, TM-265L / CAT-RT37, AD-502 / CAT-10, AD-556 / CAT-56, AD-811 / CAT-RT8, AD-817 / CAT-RT56, AD-900 / CA T-RT85 and other products manufactured by Mitsui Chemicals, Inc., including Takelac A-310 / Takenate A-3, Takelac A-315 / Takenate A-10, Takelac A-385 / Takenate A-50, Takelac A-515 / Takenate A-50, Takelac A-520 / Takenate A-50, Takelac A-525 / Takenate A-52, Takelac A-606 / Takenate Examples include Takelac A-10, Takelac A-620 / Takenate A-65, Takelac A-626 / Takenate A-50, Takelac A-627 / Takenate A-65, Takelac A-975 / Takenate A-3, etc., and Seikabond E-366 / C-83, E-370 / C-84, E-372 / C-76, A601 / C84, etc., manufactured by Dainichi Seika Kogyo Co., Ltd. Examples of polyether-based adhesive / curing agent combinations include DIC Dry LX-401A / SP-60, DIC Dry LE-3100 / SL-75, etc., manufactured by DIC Graphics Co., Ltd., and Seikabond A-159 / C-89F, etc., manufactured by Dainichi Seika Kogyo Co., Ltd. Other examples of polyurethane adhesives include one-component moisture-curing polyurethane resins (product name: Unoflex series) and two-component curing polyurethane resins (product name: Polybond series) manufactured by Sanyo Chemical Industries, Ltd. Alternatively, commercially available biomass adhesives can also be used. Commercially available adhesives and the like listed by the Japan Organic Resources Association can be used, such as DIC Dry BM (manufactured by DIC Corporation) and Takenate BM (manufactured by Mitsui Chemicals, Inc.).

[0090] The weight of the above adhesive layer after drying is 0.1 to 10 g / m². 2 Preferably, it is 1-6 g / m 2 It is more preferable that the amount be 2-5 g / m 2 It is even more preferable that this be the case.

[0091] The thickness of the adhesive layer is preferably 0.1 to 10 μm, more preferably 1 to 7 μm, and even more preferably 2 to 5 μm.

[0092] In the above-mentioned adhesive, a functional adhesive may be used. For example, as an adhesive with gas barrier properties, you can use the PASLIM series of oxygen barrier adhesives manufactured by DIC Corporation, which is a two-component curing adhesive made of polyester polyol and isocyanate compound. After the gas barrier adhesive hardens or dries, it forms a gas barrier adhesive layer. Using a gas barrier adhesive is preferable because it can further enhance the gas barrier properties of the laminate used in the present invention.

[0093] Furthermore, various adhesives can be used as the adhesive mentioned above, and it is preferable to use a pressure-sensitive adhesive. Examples of pressure-sensitive adhesives include rubber-based adhesives obtained by dissolving polyisobutylene rubber, butyl rubber, or mixtures thereof in organic solvents such as benzene, toluene, xylene, and hexane; or rubber-based adhesives obtained by compounding these rubber-based adhesives with tackifiers such as abiethylene rosin ester, terpene-phenol copolymer, and terpene-indene copolymer; or acrylic-based adhesives obtained by dissolving acrylic copolymers with a glass transition temperature of -20°C or lower, such as 2-ethylhexyl acrylate-n-butyl acrylate copolymer and 2-ethylhexyl acrylate-ethyl acrylate-methyl methacrylate copolymer, in organic solvents.

[0094] As the coating method of the above adhesive, for example, it can be applied by a direct gravure roll coating method, a gravure offset roll coating method, a kiss coating method, a reverse roll coating method, a fountain method, a transfer roll coating method, or other methods.

[0095] When the adhesive is a solvent type, the adhesive is applied to one substrate using a roll such as a gravure roll, and after the organic solvent is volatilized by heating in an oven or the like, the other substrate is laminated to obtain the laminate used in the present invention. It is preferable to perform an aging treatment after lamination. The aging temperature is preferably from room temperature to 80°C, and the aging time is preferably from 12 to 240 hours.

[0096] When the adhesive is a solvent-free type, the adhesive heated to about 40°C to 100°C in advance is applied to one substrate using a roll such as a gravure roll, and then the other substrate is immediately laminated to obtain the laminate used in the present invention. It is preferable to perform an aging treatment after lamination. The aging temperature is preferably from room temperature to 70°C, and the aging time is preferably from 6 to 240 hours.

[0097] The coating amount of the adhesive is adjusted as appropriate. In the case of a solvent type, as an example, the solid content is 1 g / m 2 or more and 10 g / m 2 or less, preferably 1 g / m 2 or more and 5 g / m 2 or less for adjustment. In the case of a solvent-free type, the coating amount of the adhesive is, as an example, 1 g / m 2 or more and 10 g / m 2 or less, preferably 1 g / m 2 or more and 5 g / m 2 or less.

[0098] (Thermoplastic resin) Furthermore, the adhesive layer can also be formed from a thermoplastic resin, and it can be formed by conventionally known methods, such as extrusion lamination or sand lamination. Examples of thermoplastic resins that can be used in the adhesive layer include ethylene-based resins such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), and high-density polyethylene (HDPE); propylene-based resins such as propylene homopolymers, propylene-α-olefin random copolymers, and propylene-α-olefin block copolymers; norbornene-based polymers such as ring-opening polymers (COP) of norbornene monomers and norbornene copolymers (COC) obtained by copolymerizing norbornene monomers with olefins such as ethylene, and their hydrogenated products; cyclic polyolefin resins such as vinyl alicyclic hydrocarbon polymers and cyclic conjugated diene polymers; and ethylene- Examples include polyethylene-based elastomers such as vinyl acetate copolymer (EVA) and ethylene-α-olefin copolymer, thermoplastic elastomers such as polypropylene-based elastomers and butene-based elastomers; ethylene-based copolymers such as ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate (EMA) copolymer, ethylene-ethyl acrylate-maleic anhydride copolymer (E-EA-MAH), ethylene-acrylic acid copolymer (EAA), and ethylene-methacrylic acid copolymer (EMAA); and further, ionomers of ethylene-acrylic acid copolymer and ionomers of ethylene-methacrylic acid copolymer. Furthermore, in order to improve the adhesion between layers, acid-modified polyolefin resins, which are obtained by modifying the above-mentioned polyolefin resin with an unsaturated carboxylic acid such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, or itaconic acid, can also be used. Furthermore, resins obtained by graft polymerization or copolymerization of polyolefin resins with unsaturated carboxylic acids, unsaturated carboxylic acid anhydrides, or ester monomers can also be used. These resins can be used individually or in combination of two or more types. Furthermore, it is also preferable to use an ethylene-based resin that uses biomass-derived ethylene as the monomer unit.

[0099] When laminating adhesive layers by extrusion lamination, an anchor coat layer may be provided on the surface of the layer being laminated, formed by applying an anchor coat agent and drying it. Examples of anchor coating agents include anchor coating agents made from any resin with a heat resistance temperature of 135°C or higher, such as polybutadiene resins, urethane resins, polyisocyanates / polyether polyols, polyethyleneimines, vinyl-modified resins, epoxy resins, polyester resins, alkyl titanates, etc., and anchor coating agents obtained by diluting the above adhesives with an organic solvent. In particular, polyethyleneimine-based anchor coating agents and anchor coating agents obtained by diluting the above adhesive with an organic solvent can be preferably used. Furthermore, a silane coupling agent may be used as an additive, and nitrated cotton may also be used to improve heat resistance.

[0100] When obtaining a laminate used in the present invention by laminating a multilayer film and a substrate, etc., using extrusion lamination or sand lamination, the nip roll and chill roll used during lamination may be replaced with embossing rolls to apply embossing to the surface on the sealing layer side.

[0101] (Printing layer) The printed layer is a layer on which letters, figures, symbols, or other desired patterns are printed. There are no particular limitations on the printing method or ink; known printing methods and inks can be used. The films used as the substrates mentioned above are often printed using methods such as gravure printing, flexographic printing, offset lithography, and inkjet printing. In addition, printing inks are also used that combine these printing methods with methods that cure them using active energy rays such as ultraviolet (UV), LEDs, and electron beams (EB), or by heat. Furthermore, depending on the solvent used, inks may also be referred to as water-based inks or organic solvent-based inks.

[0102] Specifically, these include gravure printing inks and flexographic printing inks (in some industries, gravure printing inks and flexographic printing inks are referred to as liquid printing inks), UV-curable inks for lithographic offset printing, electron beam-curable inks for lithographic offset printing, UV-curable inks for inkjet recording printing, and electron beam-curable inks for inkjet recording printing. Furthermore, the ink may be a biomass ink made from biomass raw materials, or an ink made from recycled raw materials.

[0103] The position in which the printed layer printed using these inks is provided is arbitrary; it may be provided on the above-mentioned substrate, or a substrate with a separate printed layer may be one of the components of the laminate used in the present invention, and the position is arbitrary. Furthermore, the ink may contain resin, colorant, and solvent as essential components, or it may be a so-called clear ink that contains resin and solvent but substantially no colorant.

[0104] (Barrier layer) The laminate used in the present invention may include a barrier layer. Examples of barrier layers include aluminum layers, vapor-deposited layers, and gas barrier resin layers.

[0105] For applications where transparency is not required, an aluminum layer made of aluminum foil can be used alone or in combination as a barrier layer.

[0106] (deposited layer) The laminate used in the present invention may have a vapor-deposited layer made of inorganic material and / or inorganic oxide as a barrier layer. By using this vapor-deposited layer, barrier properties can be imparted to the laminate used in the present invention. The vapor-deposited layer can be formed using known inorganic materials or inorganic oxides by known methods, and its composition and formation method are not particularly limited. Furthermore, the laminate used in the present invention may have two or more vapor-deposited films, which may have the same composition or different compositions.

[0107] As the above-mentioned vapor-deposited layer, for example, a vapor-deposited film of an inorganic substance or inorganic oxide such as silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B), titanium (Ti), lead (Pb), zirconium (Zr), or yttrium (Y) can be used. Furthermore, vapor-deposited films of inorganic oxides such as silicon oxide and aluminum oxide are transparent.

[0108] The inorganic oxides mentioned above are denoted as MOx (where M represents an inorganic element), such as SiOx and AlOx. The value of x can take on the following ranges: silicon (Si) 0-2, aluminum (Al) 0-1.5, magnesium (Mg) 0-1, calcium (Ca) 0-1, potassium (K) 0-0.5, tin (Sn) 0-2, sodium (Na) 0-0.5, boron (B) 0-1.5, titanium (Ti) 0-2, lead (Pb) 0-1, zirconium (Zr) 0-2, and yttrium (Y) 0-1.5. In the above, when x=0, it represents a completely inorganic element (pure substance), which is not transparent, and when the value of x is at the upper limit of the range, it indicates that it is completely oxidized. Silicon (Si) and aluminum (Al) are preferably used as the vapor-deposited layer. For silicon (Si), x values ​​in the range of 1.0 to 2.0 can be used, and for aluminum (Al), x values ​​in the range of 0.5 to 1.5 can be used.

[0109] The above-mentioned vapor-deposited layer can be formed on the surface of the substrate or the like by methods such as physical vapor deposition (PVD), including vacuum deposition, sputtering, and ion plating, or chemical vapor deposition (CVD), including plasma chemical vapor deposition, thermochemical vapor deposition, and photochemical vapor deposition.

[0110] The thickness of the above-mentioned vapor-deposited layer is not particularly limited as long as the vapor-deposited layer alone can exhibit a certain level of gas barrier function. The preferred thickness range varies depending on the type of metal or metal oxide being deposited, but is preferably 0.05 to 70 nm, more preferably 0.1 to 70 nm, even more preferably 3 to 70 nm, and even more preferably 5 to 60 nm.

[0111] A metal vapor-deposited film may be used as the vapor-deposited layer. As metal-deposited films, VM-CPP films, which are CPP films coated with metal such as aluminum, and VM-OPP films, which are OPP films coated with metal such as aluminum, can be used. Furthermore, examples of the transparent vapor-deposited films mentioned above include films obtained by vapor-depositing silica or alumina onto OPP film, PET film, nylon film, etc. A film with a coating applied to the vapor-deposited layer may be used for purposes such as protecting the inorganic vapor-deposited layer of silica or alumina.

[0112] (Gas barrier resin layer) (Gas barrier resin layer A) One example of a gas barrier resin layer is a gas barrier resin layer A, which can be obtained by applying a gas barrier coating agent containing a vinyl alcohol-based polymer and an aqueous solvent using a known coating method to form a coating film. Specific examples of vinyl alcohol polymers include polyvinyl alcohol, ethylene vinyl alcohol, and polyvinyl butyral. Vinyl alcohol polymers may also have reactive functional groups other than hydroxyl groups, such as acetoacetyl groups, carboxyl groups, anionic carboxyl groups, sulfonic acid groups, and anionic sulfonic acid groups. These may be used individually or in combination of two or more.

[0113] Vinyl alcohol-based polymers have excellent gas barrier properties, so a degree of saponification of 90% or more is preferable, and preferably 95% or more. It may also be 100%. The degree of saponification can be measured by FTIR using, for example, a Nicolet 5700FTIR spectrometer controlled by OMNIC software.

[0114] The gas barrier coating agent constituting the gas barrier resin layer A may further contain additives such as layered inorganic compounds, crosslinking agents that react with the functional groups of vinyl alcohol polymers, adhesion enhancers, inorganic fillers, defoamers, stabilizers (antioxidants, heat stabilizers, UV absorbers, etc.), plasticizers, antistatic agents, lubricants, antiblocking agents, colorants, and leveling agents.

[0115] The amount of gas barrier coating agent that constitutes the gas barrier resin layer A is adjusted as appropriate depending on the desired degree of gas barrier performance, but as an example, it is 0.1 g / m². 2 ~5.0g / m 2 More preferably 0.3 g / m 2 ~2.0g / m 2 That is the case.

[0116] Commercially available gas barrier coating agents can be used to constitute the gas barrier resin layer A. Examples include Exevia (registered trademark) from Sumitomo Chemical, the SunBar (registered trademark) series from Sun Chemical, the Takelac WPB (registered trademark) series from Mitsui Chemicals, and LG-OX from Tokyo Ink Co., Ltd.

[0117] (Gas barrier resin layer B) Furthermore, the gas barrier resin layer may, for example, be a water-soluble polymer having hydroxyl groups such as vinyl alcohol polymers, polyvinylpyrrolidone, starch, methylcellulose, carboxymethylcellulose, sodium alginate, and Si(OR 1 )4, or R 2 Si(OR 3 )3(However, OR 1 and OR 3 represents a hydrolyzable group, R 2 A gas barrier resin layer B can also be obtained by applying a gas barrier coating agent containing one or more silicon compounds represented by (where represents an organic functional group), or hydrolysates of said silicon compounds, and an aqueous solvent using a known coating method to form a coating film.

[0118] Since water-soluble polymers can provide good gas barrier properties, it is preferable to use vinyl alcohol-based polymers. Suitable examples of vinyl alcohol-based polymers include polyvinyl alcohol, ethylene vinyl alcohol, and polyvinyl butyral. They may be used individually or in combination of two or more. From the viewpoint of balancing gas barrier properties and adhesion, it is more preferable to use either polyvinyl alcohol or ethylene vinyl alcohol, or both, in combination.

[0119] Si(OR 1 )4, or R 2 Si(OR 3 )3(However, OR 1 and OR 3 represents a hydrolyzable group, R 2Examples of silicon compounds represented by (where represents an organic functional group), or hydrolysates of said silicon compounds, include tetraalkoxysilanes such as tetraethyl silicate (Si(OC2H5)4) (hereinafter sometimes referred to as TEOS), tetramethyl silicate, etc.; trialkoxysilanes such as trimethoxymethylsilane, triethoxymethylsilane, trimethoxyvinylsilane, etc.; dialkoxysilanes such as dimethoxydimethylsilane, diethoxydimethylsilane, etc.; monoalkoxysilanes such as methoxytrimethylsilane, ethoxytrimethylsilane, etc., or hydrolysates or partial hydrolysates thereof.

[0120] TEOS is preferred because it is relatively stable in aqueous solvents after hydrolysis. 2 Si(OR 3 )3 contains R 2 The group is preferably a vinyl group, epoxy group, acryloyl group, methacryloxy group, ureido group, or isocyanate group.

[0121] When the water-soluble polymer is a vinyl alcohol-based polymer, the ratio of the mass of the vinyl alcohol-based polymer to the mass of the total solids in the mixed solution is preferably 20% by mass or more and 50% by mass or less, and more preferably 25% by mass or more and 40% by mass or less. The inclusion of 20% by mass or more of PVA maintains the flexibility of the coating film. Therefore, the formation of the coating film is easy. Furthermore, the inclusion of 50% by mass or less of the vinyl alcohol-based polymer makes it possible to have sufficient barrier properties.

[0122] The gas barrier resin layer may contain other components. These other components may include other water-soluble polymers (e.g., sodium polyacrylate, polyethylene oxide, polyvinylpyrrolidone, dextrin, chitosan, chitin, methylcellulose, hydroxyethylcellulose, etc.), as well as fragrances, rust inhibitors, colorants, fillers, defoamers, UV absorbers, fluorescent whitening agents, liquid paraffins, bittering components (e.g., denatonium benzoate, etc.).

[0123] The thickness of the gas barrier resin layer B is preferably selected from a range of, for example, 0.05 μm to 30 μm.

[0124] (Gas barrier resin layer C) Furthermore, a gas barrier resin layer C can also be obtained by applying a gas barrier coating agent containing a polyester polyol, which is a reaction product of an acid component containing an ortho-orienting polycarboxylic acid or a meta-orienting polycarboxylic acid and a polyol component, an isocyanate compound, and an organic solvent, using a known coating method to form a coating film.

[0125] (Acid component: ortho-directing polycarboxylic acid or meta-directing polycarboxylic acid) Examples of ortho-directing polycarboxylic acids used in the synthesis of polyester polyols include orthophthalic acid or its acid anhydride, naphthalene 2,3-dicarboxylic acid or its acid anhydride, naphthalene 1,2-dicarboxylic acid or its acid anhydride, anthraquinone 2,3-dicarboxylic acid or its acid anhydride, and 2,3-anthracenecarboxylic acid or its acid anhydride. These compounds may have substituents on any carbon atom of the aromatic ring. Furthermore, examples of meta-directing polycarboxylic acids used in the synthesis of polyester polyols include isophthalic acid and 1,3-naphthalenedicarboxylic acid. These compounds may have substituents on any carbon atom of the aromatic ring.

[0126] In addition, the polycarboxylic acid may contain other known polycarboxylic acids other than the ortho-directing polycarboxylic acid or meta-directing polycarboxylic acid. When the polycarboxylic acid contains polycarboxylic acids other than ortho-directing polycarboxylic acid or meta-directing polycarboxylic acid, it is preferable that the proportion of ortho-directing polycarboxylic acid or meta-directing polycarboxylic acid to the total amount of polycarboxylic acid is 40 to 100% by mass.

[0127] (Polyol component) The polyol component polyhydric alcohol used in the synthesis of polyester polyols preferably includes dihydric alcohols such as ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexanedimethanol, and trihydric alcohols such as glycerol, trimethylolethane, and trimethylolpropane. Among these, the inclusion of ethylene glycol and glycerol is more preferable. The inclusion of glycerol is particularly preferable. Glycerol is preferably contained in the polyol component of polyol (A) at a concentration of 10 to 100% by mass. Other known polyhydric alcohols may also be used in combination. Furthermore, the polyester polyol may be a single type, or a combination of multiple polyol types may be used. The polyester polyol may also be a polyester polyurethane polyol obtained by urethane elongation through reaction with a diisocyanate compound.

[0128] The hydroxyl value of the polyester polyol is preferably 20 mg KOH / g or more and 250 mg KOH / g or less. Furthermore, if the polyester polyol has an acidic group, the acid value is preferably 200 mg KOH / g or less.

[0129] (Isocyanate compounds) The isocyanate compounds can be conventionally known compounds without particular limitation, and examples include tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, or trimers of these isocyanate compounds, and adducts obtained by reacting an excess amount of these isocyanate compounds with low molecular weight active hydrogen compounds such as ethylene glycol, propylene glycol, metaxylylene alcohol, 1,3-bishydroxyethylbenzene, 1,4-bishydroxyethylbenzene, trimethylolpropane, glycerol, pentaerythritol, erythritol, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, metaxylylenediamine and their alkylene oxide adducts, various polyester resins, polyether polyols, and high molecular weight active hydrogen compounds of polyamides. Alternatively, a polyester polyisocyanate obtained by reacting a polyester polyol with a diisocyanate compound in an isocyanate excess ratio of hydroxyl groups to isocyanate groups may be used. Blocked isocyanates may also be used. These can be used individually or in combination of two or more.

[0130] The isocyanate compound preferably has an aromatic ring or an aliphatic ring. Having an aromatic ring or an aliphatic ring can be expected to improve the gas barrier properties and blocking resistance of the coating film.

[0131] Furthermore, the polyisocyanate compound may also contain a known epoxy compound in combination with the polyisocyanate compound. When an epoxy compound is used, a commonly known epoxy curing accelerator may be added as appropriate to accelerate curing.

[0132] Furthermore, it is preferable to use a compound having an active hydrogen group in combination with the polyisocyanate compound. Examples of active hydrogen groups in the compound having an active hydrogen group include hydroxyl groups, amino groups, imino groups, carboxylic acids, urea groups, or SH groups. Among these, hydroxyl groups, amino groups, or SH groups are preferred. Among these, compound (C) having a hydroxyl group as the active hydrogen group is preferred, and isosorbide, tris(2-hydroxyethyl) isocyanurate, trimethylolpropane, dipentaerythritol, and 1,4-cyclohexanedimethanol are preferred.

[0133] The amount of the compound having the active hydrogen group is preferably 0.5% by mass or more and 20% by mass or less relative to the solid content of the gas barrier layer. Within this range, it is expected that winding blocking during coating will be prevented, good adhesion to the substrate and improved gas barrier properties of the coating film will be achieved. The amount is more preferably 1% by mass or more and 15% by mass or less, and most preferably 2% by mass or more and 8% by mass or less.

[0134] (Other ingredients) The gas barrier resin layer C may also contain, in addition to known plate-like inorganic compounds, low molecular weight organic compounds that react with oxygen, such as acid anhydrides, hindered phenols, vitamin C, vitamin E, organophosphorus compounds, gallic acid, and pyrogallol, as well as transition metal compounds such as cobalt, manganese, nickel, iron, and copper, and inorganic fillers such as silica, alumina, aluminum flakes, and glass flakes. If inorganic materials are used, dispersants, stabilizers (antioxidants, heat stabilizers, UV absorbers, etc.), plasticizers, antistatic agents, lubricants, antiblocking agents, colorants, leveling agents, slip enhancers, etc.

[0135] (Gas barrier resin layer D) Furthermore, a gas barrier resin layer D can also be obtained by applying a gas barrier coating agent containing a heteroatom compound having dehydration condensation properties, a polymer having a carboxyl group, and an organic solvent using a known coating method to form a coating film.

[0136] (Heteroatom compounds with dehydration condensation properties) A heteroatom compound having dehydration condensation properties is a compound that undergoes dehydration condensation when in contact with a compound having a hydroxyl group, and which has a heteroatom in its structure. Examples of such heteroatom compounds having dehydration condensation properties include phosphoric acid, sulfuric acid, and nitric acid. These may be used individually or in combination. Preferably, the amount of the heteroatom compound having dehydration condensation properties added to the gas barrier resin layer is 10 parts by mass or less.

[0137] (A polymer containing a carboxyl group) Examples of polymers having carboxyl groups include polymers of polymerizable unsaturated monomers having carboxyl groups, and copolymers of polymerizable unsaturated monomers having carboxyl groups and general-purpose polymerizable unsaturated monomers. Examples of polymerizable unsaturated monomers having a carboxyl group include unsaturated carboxylic acids such as (meth)acrylic acid, 2-carboxyethyl (meth)acrylate, crotonic acid, itaconic acid, maleic acid, or fumaric acid; monoesters (half-esters) of various unsaturated dicarboxylic acids such as monomethyl itaconic acid, mono-n-butyl itaconic acid, monomethyl maleic acid, mono-n-butyl maleic acid, monomethyl fumarate, and mono-n-butyl fumarate with saturated monohydric alcohols; monovinyl esters of various saturated dicarboxylic acids such as monovinyl adipate or monovinyl succinate; addition reaction products of various saturated polycarboxylic acid anhydrides such as succinic anhydride, glutaric anhydride, phthalic anhydride, or trimellitic anhydride with various hydroxyl group-containing vinyl monomers; and various monomers obtained by addition reactions of the aforementioned carboxyl group-containing monomers with lactones.

[0138] The acid value of the polymer having the carboxyl group is preferably 50 to 800 mgKOH / g, as this improves barrier performance. While there are no particular limitations on the molecular weight of the polymer having a carboxyl group, a weight-average molecular weight of 300 to 1,000,000 is preferred from the viewpoint of good film-forming properties. Particularly preferred is 500 to 500,000.

[0139] Furthermore, it is preferable that the gas barrier resin layer D has an adjacent resin layer containing a polyvalent metal compound. Here, "adjacent" means that at least a portion of the resin layers are in direct contact with each other.

[0140] Examples of polyvalent metal compounds included in the resin layer include zinc compounds, magnesium compounds, calcium compounds, manganese compounds, iron compounds, cobalt compounds, nickel compounds, and copper compounds, with zinc compounds, magnesium compounds, and calcium compounds being particularly preferred. These metal compounds may be used individually or in combination of two or more, and among them, zinc oxide, magnesium oxide, and calcium oxide are preferred. These polyvalent metal compounds are preferably included in the resin layer containing the polyvalent metal compounds in an amount of 40 to 90 parts by mass.

[0141] In addition to the polyvalent metal compound, the resin layer containing the polyvalent metal compound preferably also contains ethyl cellulose resin, polyether polyurethane polyol resin, polyester polyol resin, and polyurethane polyol resin in order to stably coat the polyvalent metal compound. The resin is preferably contained in the resin layer containing the polyvalent metal compound in an amount of 10 to 60 parts by mass.

[0142] Furthermore, it is preferable that the gas barrier resin layer D has an adjacent layer containing aluminum oxide, silicon oxide, or silicon nitride, etc. These adjacent layers are formed by depositing a compound selected from the group consisting of aluminum oxide, silicon oxide, and silicon nitride by processes such as vapor deposition, sputtering, and CVD. These layers may be formed on a base film such as polyethylene terephthalate (PET) resin film, polypropylene (PP) resin film, polybutylene terephthalate (PBT) resin film, nylon (NY) resin film, or biomass film. These base films may be films manufactured by various known processes such as biaxially oriented films, stretched films, or unstretched films, or films that have undergone various surface treatments as needed.

[0143] The gas barrier resin layer D should be applied in an amount of 0.01 to 100 g / m² after drying. 2 Preferably, 0.1 to 50 g / m 2 More preferably, 0.5-3 g / m 2 That is particularly preferable.

[0144] [Lid material] The multilayer film used in the present invention may be used as a lid material as is, or it is preferable to use a lid material consisting of a laminate in which a base material is laminated onto the surface layer (A). When used as the base material for the lid material, there are no particular restrictions as long as it does not impair sealing properties or deadhold properties, but examples include biaxially oriented polyester (PET), easily tearable biaxially oriented polyester (PET), biaxially oriented polypropylene (OPP), co-extruded biaxially oriented polypropylene with ethylene vinyl alcohol copolymer (EVOH) as the core layer, biaxially oriented ethylene vinyl alcohol copolymer (EVOH), co-extruded biaxially oriented polypropylene coated with polyvinylidene chloride (PVDC), biaxially oriented nylon, etc. One or more of these base films may be used in combination, but from the viewpoint of monomaterialization, it is preferable that the film to be laminated is a polyester resin such as biaxially oriented polyester (PET) and easily tearable biaxially oriented polyester (PET). Adhesion methods include the aforementioned dry lamination, wet lamination, non-solvent lamination, and extrusion lamination.

[0145] The above-mentioned lid material is used to seal and tightly seal a container having an opening. This lid material is preferably applicable to containers having an opening, where the material of the outermost layer (the part to which the lid material is heat-sealed) is selected from one or more of the following: glass, aluminum, polyimide, nylon, acrylic acid ester, high-impact polystyrene (HIPS), polylactic acid, polyvinyl chloride, polycarbonate, and acrylonitrile-butadiene-styrene resin (ABS).

[0146] [Containers and packaging] The container packaging of the present invention is a container packaging having an adherend that adheres to the seal layer (D) of a multilayer film or laminate used in the present invention, wherein the surface material of the adherend is one or more selected from glass, aluminum, polyimide, nylon, acrylic acid ester, high-impact polystyrene (HIPS), polylactic acid, polyvinyl chloride, polycarbonate, and acrylonitrile-butadiene-styrene resin (ABS).

[0147] The seal layer (D) of the multilayer film or laminate used in the present invention preferably has heat-sealability to one or more materials selected from glass, aluminum, polyimide, nylon, acrylic acid ester, polystyrene, polylactic acid, polyvinyl chloride, polycarbonate, and acrylonitrile-butadiene-styrene resin (ABS), more preferably to two or more, even more preferably to four or more, and particularly preferably to all of them. Here, "having heat-sealing properties" means that when the adherend and the multilayer film used in the present invention are superimposed so that the sealing layer (D) side becomes the heat-sealing surface, and the upper heat-sealing bar, adjusted to a temperature of 200°C, is set to face the surface layer (A) of the laminate using a heat-sealing tester (precision heat sealer manufactured by Tester Industries), and heat-sealed under conditions of 0.2 MPa and 1 second, the heat-sealing strength is 7 N / 15 mm or more. Since the multilayer film used in this invention can adhere to a variety of substrates, there is no need to prepare custom-made films for multiple substrates, which improves work efficiency and reduces management costs.

[0148] Examples of containers and packaging made from the multilayer film or laminate used in the present invention include packaging bags and packaging containers used for food, pharmaceuticals, industrial parts, general merchandise, magazines, and the like. In this invention, the term "container and packaging" also includes containers such as glass bottles and metal cans that are integrated with the multilayer film or laminate used in the present invention. For example, the packaging bag can be made by cutting the multilayer film and the adherend film to the desired size of the packaging bag, overlapping them, sealing three sides to form a bag, and then filling the contents through the unsealed side and sealing it to create a sealed packaging bag. Furthermore, it is also possible to form a packaging bag by sealing the ends of a roll of film into a cylindrical shape using an automatic packaging machine, and then sealing the top and bottom. Furthermore, the packaging bag can also be made from a laminate using the multilayer film used in the present invention.

[0149] As for the bag-making method, one method involves overlapping the inner layer surface (seal layer (D) surface) of the multilayer film or laminate used in the present invention with a substrate whose surface material is one or more selected from, for example, aluminum, polyimide, nylon, acrylic acid ester, polystyrene, polylactic acid, polyvinyl chloride, polycarbonate, and acrylonitrile-butadiene-styrene resin (ABS), and then heat-sealing the peripheral edges in a form such as a side seal type, two-sided seal type, three-sided seal type, four-sided seal type, envelope seal type, gusset seal type, pleated seal type, flat-bottom seal type, square-bottom seal type, gusset type, or other heat-seal type. The container packaging of the present invention can take various forms depending on the contents, usage environment, and usage form. It is also possible to manufacture bags in various shapes such as self-standing container packaging (standing pouch), tube type, and sachet (small bag). As for the heat-sealing method, known methods such as bar seal, rotary roll seal, belt seal, impulse seal, high-frequency seal, and ultrasonic seal can be used.

[0150] In containers and packaging using the multilayer film or laminate used in the present invention, it is preferable to form arbitrary tear-initiating sections such as V-notches, I-notches, perforations, or micropores in the seal portion in order to weaken the initial tear strength and improve ease of opening.

[0151] Products using the container packaging of the present invention are manufactured by filling the container packaging with contents through its opening and then heat-sealing the opening. Examples of contents that can be filled include, for example, food products such as rice crackers, bean snacks, nuts, biscuits / cookies, wafers, marshmallows, pies, semi-baked cakes, candies, and snack foods; staples such as bread, instant noodles, dried noodles, pasta, aseptically packaged rice, rice porridge, packaged mochi, and cereal foods; processed agricultural products such as pickles, boiled beans, natto, miso, frozen tofu, tofu, enoki mushrooms, konjac, processed wild vegetables, jams, peanut cream, salads, frozen vegetables, and processed potato products; processed livestock products such as ham, bacon, sausages, processed chicken products, and corned beef; and fish products. Examples of processed seafood products include sausages, processed seafood products, fish cakes, seaweed, preserved foods, dried bonito flakes, salted seafood, smoked salmon, spicy cod roe, and other processed seafood products; fruits such as peaches, oranges, pineapples, apples, pears, and cherries; vegetables such as corn, asparagus, mushrooms, onions, carrots, radishes, and potatoes; frozen and chilled prepared foods such as hamburgers, meatballs, fried seafood, dumplings, and croquettes; dairy products such as butter, margarine, cheese, cream, instant creamy powder, and infant formula; liquid seasonings; retort curry; and pet food.

[0152] Furthermore, as a non-food product, it can be used as a container and packaging material for various items such as cigarettes, disposable hand warmers, pharmaceuticals such as intravenous fluid packs, liquid laundry detergent, liquid dish soap, liquid bath detergent, liquid bath soap, liquid shampoo, liquid conditioner, cosmetics such as lotions and emulsions, deodorizers, air fresheners, vacuum insulation materials, and batteries. [Examples]

[0153] Next, the present invention will be described in more detail with reference to examples and comparative examples. Hereinafter, unless otherwise specified, "parts" and "%" refer to mass.

[0154] (Manufacturing Example 1) The resins and resin mixtures forming each of the surface layer (A), intermediate layer (B), intermediate layer (C), and seal layer (D) were prepared using the following resins, respectively. These resins and resin mixtures were supplied to an extruder and melted. The molten resin was then supplied to a T-die chill-roll co-extrusion multilayer film manufacturing apparatus equipped with a feed block. By co-melt extrusion, a multilayer film was obtained with a four-layer structure consisting of a surface layer (A), intermediate layer (B), intermediate layer (C), and seal layer (D), with thickness ratios of 20% / 50% / 10% / 20% for each layer and a total thickness of 30 μm. Surface layer (A): Crystalline polyester 1 (a1) (melting point 165°C, glass transition temperature -32°C) 10 parts, amorphous polyester 1 (a2) (glass transition temperature 72°C) 80 parts, propylene block copolymer 2 (a3) ​​(melt flow rate (MFR) (230°C, 21.18N) 2.3 g / 10 min, density 0.9 g / cm³) 3 Melting point 167°C, cloudiness during film formation 70%) 10 parts Intermediate layer (B): 10 parts crystalline polyester 1(b1), 90 parts amorphous polyester 1(b2) Intermediate layer (C): 10 parts crystalline polyester 1(c1), 90 parts amorphous polyester 1(c2) Seal layer (D): Crystalline polyester 1 (d1) 80 parts, amorphous polyester 1 (d2) 10 parts, propylene block copolymer 2 (d3) 10 parts

[0155] (Manufacturing example 2, comparative manufacturing examples 1-2) Multilayer films for Manufacturing Example 2 and Comparative Manufacturing Examples 1-2 were obtained in the same manner as in Manufacturing Example 1, except that the composition of each layer of the multilayer film was changed as shown in Table 1.

[0156] [Seal strength evaluation 1] The multilayer films of the manufacturing example and comparative manufacturing example were bonded to a biaxially oriented polyester film with a thickness of 12 μm using a dry laminating adhesive. After aging at 40°C for 24 hours, the laminates were cut to 10 cm x 10 cm to obtain laminated bodies (laminate films). The laminates obtained above and various adherends were placed on top of each other so that the seal layer (D) side of the laminate became the heat-sealing surface. Using a heat seal tester (precision heat sealer manufactured by Tester Industries), the upper heat seal bar, adjusted to a temperature of 200°C, was set so that it was on the surface layer (A) side of the laminate, and heat sealing was performed under conditions of 0.2 MPa and 1 second. The obtained samples were cut into 15 mm widths and tested using a tensile testing machine (manufactured by A&D Co., Ltd.). The maximum strength obtained when peeled at a speed of 300 mm / min was defined as the seal strength and evaluated according to the following criteria. ◎: 10N / 15mm or more ○: 7N / 15mm or more, less than 10N / 15mm ×: Less than 7N / 15mm The following materials were used as adherends. • Crystallized polyethylene terephthalate (C-PET) (thickness 0.3 mm) • Glass (1.0mm thick) • Aluminum foil (0.1mm thick) • Polyimide (thickness 0.1 mm) • Nylon (thickness 0.025mm) The results are shown in Table 2.

[0157] [Seal strength evaluation 2] The multilayer film from Manufacturing Example 1 and a biaxially oriented polyester film with a thickness of 12 μm were bonded together using a dry laminating adhesive. After aging at 40°C for 24 hours, the laminate was cut to a size of 10 cm x 10 cm to obtain a laminate (laminate film). The laminate obtained above and various adherends were placed on top of each other so that the sealing layer (D) side of the laminate became the heat-sealing surface. Using a heat seal tester (precision heat sealer manufactured by Tester Industries), the upper heat seal bar, adjusted to a temperature of 200°C, was set so that it was on the surface layer (A) side of the laminate, and heat sealing was performed under conditions of 0.2 MPa and 1 second. The obtained samples were cut into 15 mm widths and tested using a tensile testing machine (manufactured by A&D Co., Ltd.). The maximum strength obtained when peeled at a speed of 300 mm / min was defined as the seal strength. The evaluation criteria were the same as those for seal strength evaluation 1. The following materials were used as adherends. • Acrylic (acrylic acid ester) (thickness 0.8mm) • High-impact polystyrene (HIPS) (0.1mm thickness) • Polylactic acid (thickness 0.1 mm) • Polyvinyl chloride (thickness 0.8mm) • Polycarbonate (0.8mm thick) • ABS (Acrylonitrile Butadiene Styrene resin) (thickness 0.8mm) The results are shown in Table 2.

[0158] [Deodorizer Packet Evaluation] The multilayer film of Manufacturing Example 1 was laminated using a dry laminating adhesive in the order of a 12 μm thick biaxially oriented polyester film, a 9 μm thick aluminum film, and a laminated film. After aging at 40°C for 24 hours, it was cut to a size of 10 cm x 10 cm to obtain a laminate (laminate film). The laminate obtained above and a rectangular A-PET container with dimensions of 88 mm x 88 mm x 27 mm containing 20 g of contents were placed on top of each other so that the heat-seal layer (D) side of the laminate faced the cup flange side. Then, using a cup sealer manufactured by Shinwa Machinery, the container was heat-sealed at approximately 100 kg for 1 second using an upper heat-sealing mold adjusted to 175°C. The contents were "Shoshugen, Refreshing Sparkling Lemon" (Kobayashi Pharmaceutical Co., Ltd.) (hereinafter referred to as Deodorant 1), "Shoshugen, Fluffy Clean Soap" (Kobayashi Pharmaceutical Co., Ltd.) (hereinafter referred to as Deodorant 2), "Shoshugen, Aroma Chamomile" (Kobayashi Pharmaceutical Co., Ltd.) (hereinafter referred to as Deodorant 3), and "Fragrance-Free Space" (Kobayashi Pharmaceutical Co., Ltd.) (hereinafter referred to as Deodorant 4). The obtained heat-sealed samples were stored at 50°C for one month, then removed and left at 23°C and 50% RH for 24 hours to prepare samples for measurement. A 15 mm wide strip of the inner film portion of the heat-sealed flange was cut, grasped with the tip of a push-pull gauge, and the maximum strength when the lid material was peeled off at a 90-degree angle from the horizontal plane of the flange was defined as the seal strength. The evaluation criteria were the same as for seal strength evaluation 1. The evaluation results are shown in Table 3.

[0159] [Table 1]

[0160] Details of each resin in Table 1 are as follows: Crystalline polyester 1: Melting point 165°C, glass transition temperature -32°C Crystalline polyester 2: Melting point 126°C, glass transition temperature -70°C Amorphous polyester 1: Glass transition temperature 72°C Propylene block copolymer 1: MFR (230℃, 21.18N) 2.0g / 10min, density 0.9g / cm³ 3 Melting point 165°C, cloudiness level during film formation 52% Propylene block copolymer 2: Melt flow rate (MFR) (230℃, 21.18N) 2.3g / 10min, density 0.9g / cm³ 3 Melting point 167°C, cloudiness level during film formation 70%

[0161] [Table 2]

[0162] [Table 3]

[0163] As is clear from the table above, the container packaging of the present invention in the examples showed good sealing strength regardless of the substrate to which it was applied. On the other hand, the comparative example had a limited range of adherends to which it could be bonded.

Claims

1. A multilayer film having a sealing layer (D) and a surface layer (A), and an adherend that adheres to the sealing layer (D) of the multilayer film, The surface material of the adherend is one or more selected from glass, aluminum, polyimide, nylon, acrylic acid ester, high-impact polystyrene (HIPS), polylactic acid, polyvinyl chloride, polycarbonate, and acrylonitrile-butadiene-styrene resin (ABS). The sealing layer (D) contains 65 to 95% by mass of crystalline polyester (d1). Container packaging.

2. The container packaging according to claim 1, wherein the sealing layer (D) further contains 1 to 35% by mass of amorphous polyester (d2) and / or polyolefin resin (d3).

3. The sealing layer (D) contains 70 to 95% by mass of crystalline polyester (d1), The container and packaging according to claim 1, comprising 1 to 30% by mass of a polyolefin resin (d3).

4. The container packaging according to claim 1, wherein the multilayer film further comprises an intermediate layer (C).

5. The intermediate layer (C) is directly laminated with the sealing layer (D), The intermediate layer (C) contains crystalline polyester (c1) and / or amorphous polyester (c2), The sealing layer (D) contains a crystalline polyester (d1) and an amorphous polyester (d2), The sum of the mass ratio of the crystalline polyester (d1) in the resin component contained in the sealing layer (D) and the mass ratio of the crystalline polyester (c1) in the resin component contained in the intermediate layer (C), The difference between the mass ratio of the amorphous polyester (d2) in the resin component contained in the sealing layer (D) and the total mass ratio of the amorphous polyester (c2) in the resin component contained in the intermediate layer (C) is within 60% by mass. The container packaging according to claim 4.

6. The laminate comprises a multilayer film having a sealing layer (D) and a surface layer (A), and an adherend that adheres to the sealing layer (D) of the multilayer film. The surface material of the adherend is one or more selected from glass, aluminum, polyimide, nylon, acrylic acid ester, high-impact polystyrene (HIPS), polylactic acid, polyvinyl chloride, polycarbonate, and acrylonitrile-butadiene-styrene resin (ABS). The sealing layer (D) contains 65 to 95% by mass of crystalline polyester (d1). Container packaging.

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