Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/32—Layered products comprising a layer of synthetic resin comprising polyolefins
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
  • B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/28—Layered products comprising a layer of synthetic resin comprising synthetic resins not wholly covered by any one of the sub-groups B32B27/30 - B32B27/42
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
  • B32B27/304—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
  • B32B27/306—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising vinyl acetate or vinyl alcohol (co)polymers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
  • B32B27/308—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising acrylic (co)polymers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/34—Layered products comprising a layer of synthetic resin comprising polyamides
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/36—Layered products comprising a layer of synthetic resin comprising polyesters
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B37/00—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding
  • B32B37/14—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers
  • B32B37/15—Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the properties of the layers with at least one layer being manufactured and immediately laminated before reaching its stable state, e.g. in which a layer is extruded and laminated while in semi-molten state
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
  • B32B7/04—Interconnection of layers
  • B32B7/12—Interconnection of layers using interposed adhesives or interposed materials with bonding properties
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
  • B65D65/00—Wrappers or flexible covers; Packaging materials of special type or form
  • B65D65/38—Packaging materials of special type or form
  • B65D65/40—Applications of laminates for particular packaging purposes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B2255/00—Coating on the layer surface
  • B32B2255/10—Coating on the layer surface on synthetic resin layer or on natural or synthetic rubber layer
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B2255/00—Coating on the layer surface
  • B32B2255/20—Inorganic coating
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B2255/00—Coating on the layer surface
  • B32B2255/20—Inorganic coating
  • B32B2255/205—Metallic coating
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B2307/00—Properties of the layers or laminate
  • B32B2307/30—Properties of the layers or laminate having particular thermal properties
  • B32B2307/304—Insulating
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B2307/00—Properties of the layers or laminate
  • B32B2307/50—Properties of the layers or laminate having particular mechanical properties
  • B32B2307/514—Oriented

Definitions

• the present invention relates to a multilayer film for vacuum insulation, a vapor-deposited multilayer film for vacuum insulation, a multilayer structure for vacuum insulation, a vacuum packaging bag, and a vacuum insulation material.
• insulation materials using polyurethane foam have been used as insulation for refrigerators, insulation panels for insulated residential walls, and hot water tanks.
• vacuum insulation materials which are made up of a laminate film that has gas barrier properties even in high humidity and a core material such as glass fiber with low thermal conductivity, are beginning to be used.
• Aluminum foil is mainly used as a gas barrier material, but because aluminum is a good conductor of heat, a large amount of heat passes through the aluminum part of the film, which has the disadvantage of reducing the insulation performance.
• high gas barrier films such as polyester films with a thin aluminum vapor deposition layer and ethylene-vinyl alcohol copolymer (hereinafter sometimes abbreviated as EVOH) films are being considered instead of aluminum foil.
• Patent Document 1 describes a method for suppressing the loss of gas barrier properties due to bending, in which a deposition film comprising a base film containing a polyvinyl alcohol-based polymer and a metal deposition layer laminated on the base film, the metal deposition layer having an average particle size of 150 nm or less as measured by an electron microscope, can suppress the loss of gas barrier properties due to bending.
• Patent Document 2 describes, as another method, a multilayer structure comprising an inorganic deposition layer and an overcoat layer containing modified polyvinyl alcohol on a biaxially stretched polyvinyl alcohol-based resin film, which has excellent bending resistance.
• Patent Document 3 describes that by co-extruding polypropylene and ethylene-vinyl alcohol copolymer and biaxially stretching it, it has been confirmed that heat shrinkage wrinkles and sagging during vapor deposition can be reduced, and lamination film productivity can be improved.
• the present invention was made based on these circumstances, and aims to provide a multilayer film for vacuum insulation materials that can reduce the defect rate during the production of the vacuum insulation material and the defect rate after the vacuum insulation material is bent.
• the above object is to [1] A multilayer film for a vacuum insulation material, comprising an EVOH layer (A), an adhesive layer (B) and a thermoplastic resin layer (C) in this order, in which the EVOH layer (A) contains, as a main component, EVOH (a) having an ethylene unit content of 20 mol% or more and 30 mol% or less, the adhesive layer (B) contains, as a main component, an adhesive resin (b), and the thermoplastic resin layer (C) contains, as a main component, polyethylene (c), and is stretched at least 3 times and 12 times in at least one axial direction; [2] The multilayer film for vacuum cutting according to [1], wherein the average thickness of the EVOH layer (A) is 10 ⁇ m or less; [3] The multilayer film for vacuum insulation materials according to [1] or [2], in which the melt flow rate of EVOH (a) at 210 ° C.
• the present invention provides a multilayer film for vacuum insulation material that can reduce the defect rate during the production of vacuum insulation material and the defect rate after bending the vacuum insulation material, as well as a vapor-deposited multilayer film for vacuum insulation material, a multilayer structure for vacuum insulation material, a vacuum packaging bag, and a vacuum insulation material that use the multilayer film.
• gas barrier properties mainly refers to oxygen barrier properties.
• the property of keeping the thermal conductivity low after bending storage is sometimes expressed as “bending storage properties.”
• Main component refers to the component that is contained most abundantly by mass.
• outermost layer is not limited to the layer present on the outermost side, with a distinction between the outermost and innermost sides.
• a multilayer film, a vapor-deposited multilayer film, or a multilayer structure consisting of two or more layers has two outermost layers, an outermost layer on one side and an outermost layer on the other side.
• the inner outermost layer is sometimes called the innermost layer
• the outermost layer on the outside is sometimes called the outermost layer.
• the term "average thickness” refers to the average value of thicknesses measured at any five points.
• the multilayer film for vacuum insulation materials of the present invention may be simply referred to as a "multilayer film".
• the multilayer film for vacuum insulation materials of the present invention comprises an EVOH layer (A), an adhesive layer (B) and a thermoplastic resin layer (C) in this order, the EVOH layer (A) containing EVOH (a) having an ethylene unit content of 20 mol% or more and 30 mol% or less as a main component, the adhesive layer (B) containing an adhesive resin (b) as a main component, the thermoplastic resin layer (C) containing polyethylene (c) as a main component, and stretched at least uniaxially 3 times or more and 12 times or less.
• EVOH layer (A), an adhesive layer (B) and a thermoplastic resin layer (C) in this order means that as long as the EVOH layer (A), the adhesive layer (B) and the thermoplastic resin layer (C) are laminated in this order, there may be another layer between each layer, but it is preferable that each layer is directly laminated, i.e., the EVOH layer (A), the adhesive layer (B) and the thermoplastic resin layer (C) are directly laminated in this order.
• the multilayer film for vacuum insulation materials of the present invention has good puncture strength by comprising an EVOH layer (A), an adhesive layer (B), and a thermoplastic resin layer (C) in this order, and therefore tends to prevent the core material from breaking through, which is thought to improve yield.
• the multilayer film for vacuum insulation materials of the present invention has such a layer structure, when, for example, the average thickness of the EVOH layer (A) is to be reduced to reduce costs, it can be made thinner to a level that cannot be achieved with a single EVOH layer, and further, sufficient puncture strength can be maintained even when the EVOH layer (A) is made thinner, so that in one embodiment of the present invention, a high yield can be achieved while reducing costs.
• the multilayer film using polypropylene described in Patent Document 3 can somewhat prevent the core material from penetrating through, but because polypropylene has a high hardness, there is a high probability of damage such as cracks occurring in the deposition layer at the edge of the vacuum insulation material during production and bending of the vacuum insulation material, making it difficult to achieve a high level of yield improvement.
• the multilayer film of the present invention has a thermoplastic resin layer (C) containing polyethylene (c) as the main component, the flexibility of the multilayer film is improved compared to polypropylene, and it is thought that there is a tendency to reduce the defect rate during production of the vacuum insulation material and the defect rate after bending the vacuum insulation material.
• the thermal shrinkage of the EVOH layer (A) can be suppressed, and the defective rate during the production of the vacuum insulation material tends to be reduced.
• a multilayer film having an EVOH layer (A), an adhesive layer (B), and a thermoplastic resin layer (C) containing polyethylene (c) as a main component in this order and stretched at least uniaxially by 3 times or more and 12 times or less if the ethylene unit content of the EVOH contained in the EVOH layer (A) exceeds 30 mol%, the defective rate during the production of the vacuum insulation material and when the vacuum insulation material is bent is found to increase.
• the multilayer film of the present invention tends to have the surprising effect of reducing the defect rate during the production of the vacuum insulation material and when the vacuum insulation material is bent, by using EVOH (a) as the main component, which has a relatively low ethylene unit content of 20 mol% to 30 mol%.
• the EVOH layer (A) contains, as a main component, EVOH (a) having an ethylene unit content of 20 mol % or more and 30 mol % or less.
• EVOH (a) As a main component, the puncture strength of the multilayer film is The adhesiveness between the EVOH layer (A) and the inorganic vapor deposition layer (D) described later is improved. As a result, the defective rate of the vacuum insulation material and the defective rate after bending are reduced. The thermal conductivity of the vacuum insulation material also decreases after it is stored while being bent.
• the EVOH constituting the EVOH (a) one or more kinds can be used.
• EVOH (a) can usually be obtained by saponifying an ethylene-vinyl ester copolymer.
• the production and saponification of the ethylene-vinyl ester copolymer can be carried out by known methods.
• a typical vinyl ester is vinyl acetate, but other fatty acid vinyl esters such as vinyl formate, vinyl propionate, vinyl valerate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl pivalate, and vinyl versatate may also be used.
• the ethylene unit content of EVOH (a) is 20 mol% or more, preferably 22 mol% or more, more preferably 23 mol% or more, and may be 25 mol% or more.
• the ethylene unit content of EVOH (a) is 30 mol% or less, preferably 28 mol% or less.
• the flexibility is improved, so that the damage to the inorganic vapor deposition layer (D) described later when bending is reduced, and the defective rate of the vacuum insulation material after bending tends to decrease.
• the ethylene unit content is 30 mol% or less, the puncture strength of the multilayer film tends to increase.
• the ethylene unit content of EVOH can be determined by a nuclear magnetic resonance (NMR) method.
• the saponification degree of EVOH (a) (the ratio (mol %) of vinyl alcohol units to the total of vinyl alcohol units and vinyl ester units) is preferably 90 mol % or more, more preferably 98 mol % or more, and even more preferably 99 mol % or more. On the other hand, the saponification degree may be 100 mol % or less.
• the saponification degree of EVOH can be determined by a nuclear magnetic resonance (NMR) method. When the saponification degree is within the above range, the gas barrier property of the multilayer film under high humidity conditions tends to be improved.
• EVOH (a) may have units derived from other monomers other than ethylene, vinyl esters and their saponification products, to the extent that the object of the present invention is not hindered.
• the content of the other monomer units relative to the total structural units of EVOH (a) is preferably 30 mol% or less, more preferably 15 mol% or less, even more preferably 5 mol% or less, and particularly preferably 1 mol% or less, and EVOH (a) may not contain other monomer units.
• the lower limit may be 0.05 mol% or more or 0.1 mol% or more.
• EVOH (a) contains units derived from the other monomers, the puncture strength tends to decrease, and there is a concern that the defective rate during the production of vacuum insulation materials may increase, so it is preferable that EVOH (a) does not contain units derived from the other monomers.
• Examples of the other monomers include alkenes such as propylene, butylene, pentene, and hexene; 3-acyloxy-1-propene, 3-acyloxy-1-butene, 4-acyloxy-1-butene, 3,4-diacyloxy-1-butene, 3-acyloxy-4-methyl-1-butene, 4-acyloxy-2-methyl-1-butene, 4-acyloxy-3-methyl 1-butene, 3,4-diacyloxy-2-methyl-1-butene, 4-acyloxy-1-pentene, 5-acyloxy-1-pentene, 4,5-diacyloxy-1-pentene, 4-acyloxy-1-hexene, 5-acyloxy-1-hexene, 6-acyloxy-1-hexene, 5,6-diacyloxy-1-hexene, 1,3-diacetoxy-2-methyl alkenes having an ester group such as dimethylpropane or saponified products thereof; unsaturated acids such as acrylic
• EVOH (a) may be post-modified by methods such as urethanization, acetalization, cyanoethylation, and oxyalkylenation.
• the melt flow rate of EVOH (a) measured at 210°C under a load of 2,160 g in accordance with the method described in ISO 1133-1:2011 is preferably 1 g/10 min to 10 g/10 min, more preferably 1 g/10 min to 8 g/10 min.
• the EVOH layer (A) may contain other components, such as antiblocking agents, processing aids, resins other than EVOH (a), carboxylic acid compounds, phosphoric acid compounds, boron compounds, metal salts, stabilizers, antioxidants, UV absorbers, plasticizers, antistatic agents, lubricants, colorants, fillers, surfactants, drying agents, crosslinking agents, reinforcing agents such as various fibers, etc., so long as the effects of the present invention are not impaired.
• the content of other components in the EVOH layer (A) may be 5% by mass or less, 3% by mass or less, 1% by mass or less, or 0.5% by mass or less.
• the EVOH layer (A) does not contain, as a resin other than EVOH (a), EVOH with an ethylene unit content of more than 30 mol%.
• EVOH (a) may contain two or more types of EVOH with different ethylene unit contents, but it is preferable that the ethylene unit contents of the EVOH constituting EVOH (a) are the same, from the viewpoint of reducing thickness unevenness during stretching and, as a result, suppressing an increase in thermal conductivity after bending and storage of the vacuum insulation body.
• the proportion of EVOH (a) in the resin constituting the EVOH layer (A) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, particularly preferably 95% by mass or more, and may be 99% by mass or more, and the resin constituting the EVOH layer (A) may be substantially composed of EVOH (a) alone, or may be composed of EVOH (a) alone.
• the proportion of EVOH (a) in the EVOH layer (A) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, particularly preferably 95% by mass or more, and may be 99% by mass or more.
• the lower limit of the average thickness of the EVOH layer (A) is preferably 0.1 ⁇ m or more, more preferably 0.3 ⁇ m or more, even more preferably 0.7 ⁇ m or more, even more preferably 1.5 ⁇ m or more, and may be 2 ⁇ m or more or 2.5 ⁇ m or more.
• the average thickness of the EVOH layer (A) is equal to or more than the above lower limit, the puncture strength of the multilayer film tends to be further increased.
• the defect rate of the vacuum insulation material before and after bending also tends to be further reduced.
• the thermal conductivity of the vacuum insulation material after bending and storage also tends to be further reduced.
• the upper limit of the average thickness of the EVOH layer (A) is preferably 10 ⁇ m or less, more preferably 8 ⁇ m or less, even more preferably 7 ⁇ m or less, particularly preferably 5 ⁇ m or less, and most preferably 4 ⁇ m or less.
• the average thickness of the EVOH layer (A) is equal to or less than the above upper limit, the defect rate of the vacuum insulation material before and after bending both tends to be reduced. Furthermore, by making the EVOH layer (A) thinner, the amount of EVOH (a) used is reduced, leading to cost savings.
• the average thickness of the EVOH layer (A) can be reduced to 10 ⁇ m or less only by stretching a multilayer film having an adhesive layer (B) and a thermoplastic resin layer (C) described below.
• the average thickness of the EVOH layer (A) refers to the average thickness after stretching.
• the EVOH layer (A) may consist of a single layer or multiple layers. When the EVOH layer (A) consists of multiple layers, it is preferable that the total average thickness is within the above range.
• the adhesive layer (B) contains the adhesive resin (b) as a main component. This tends to improve the interlayer adhesion of the multilayer film for vacuum insulation materials.
• the content of the adhesive resin (b) in the adhesive layer (B) is preferably 50% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and may be 95% by mass or more, 99% by mass or more, or 99.9% by mass or more.
• the content of the adhesive resin (b) in the adhesive layer (B) may be 100% by mass or less, or may be 99.99% by mass or less.
• polyethylene having a carboxy group, a carboxylic anhydride group, or an epoxy group is preferred, and polyethylene having a carboxylic anhydride group is more preferred.
• polyethylene containing carboxyl groups examples include polyethylene copolymerized with acrylic acid or methacrylic acid. In this case, all or part of the carboxyl groups contained in the polyethylene may be present in the form of a metal salt, as typified by ionomers.
• polyethylene having carboxylic anhydride groups examples include polyethylene graft-modified with maleic anhydride or itaconic acid.
• polyethylene having epoxy groups examples include polyethylene copolymerized with glycidyl methacrylate. Of these, polyethylene having carboxylic anhydride groups such as maleic anhydride can be preferably used.
• the melt flow rate of adhesive resin (b) measured at 210°C under a load of 2160 g in accordance with the method described in ISO1133-1:2011 is preferably 0.1 to 20 g/10 min, more preferably 1 to 10 g/10 min.
• the melt flow rate of adhesive resin (b) is within the above range, the film formation stability tends to be good.
• the average thickness of the adhesive layer (B) is preferably 0.1 to 20 ⁇ m, more preferably 0.3 to 10 ⁇ m, even more preferably 0.5 to 5 ⁇ m, and may be 0.5 to 3 ⁇ m.
• the average thickness of the adhesive layer (B) means the average thickness after stretching.
• thermoplastic resin layer (C) contains polyethylene (c) as a main component.
• polyethylene (c) as a main component, the puncture strength of the multilayer film is improved, so that the defect rate of the vacuum insulation material before and after bending is In addition, since the stretching ratio can be increased while maintaining the performance of the multilayer film, the film can be made thinner, leading to cost reduction.
• the content of is preferably 50% by mass or more, more preferably 80% by mass or more, further preferably 90% by mass or more, and may be 95% by mass or more, 99% by mass or more, or 99.9% by mass or more.
• the content of the polyethylene (c) in the plastic resin layer (C) may be 100% by mass or less, or may be 99.99% by mass or less.
• the polyethylene (c) is preferably at least one selected from linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE) and high density polyethylene (HDPE), and more preferably at least one selected from linear low density polyethylene and low density polyethylene, or a mixture of at least one selected from linear low density polyethylene and low density polyethylene and high density polyethylene.
• LLDPE linear low density polyethylene
• LDPE low density polyethylene
• MDPE medium density polyethylene
• HDPE high density polyethylene
• the linear low-density polyethylene may be an ethylene polymer or ethylene copolymer polymerized using a metallocene catalyst.
• the ethylene polymer or ethylene copolymer polymerized using a metallocene catalyst is an ethylene homopolymer or a copolymer of ethylene and an ⁇ -olefin having 3 or more carbon atoms, which is produced by polymerizing ethylene or copolymerizing ethylene and the ⁇ -olefin in the presence of a catalyst formed from a compound of a transition metal of Group 4 of the periodic table, preferably zirconium, having at least one ligand having a cyclopentadienyl skeleton, an organoaluminum oxy compound, and various components added as necessary.
• the melt flow rate of polyethylene (c) at 210°C under a load of 2160 g, measured in accordance with the method described in ISO 1133-1:2011, is preferably 0.1 to 20 g/10 min, more preferably 0.1 to 10 g/10 min, even more preferably 0.1 to 5 g/10 min, and may be 0.1 to 3 g/10 min.
• the melt flow rate of polyethylene (c) is within the above range, the film formation stability tends to be good.
• the average thickness of the thermoplastic resin layer (C) is preferably 5 to 200 ⁇ m, more preferably 7 to 100 ⁇ m, and even more preferably 10 to 50 ⁇ m.
• the average thickness of the thermoplastic resin layer (C) means the average thickness after stretching.
• the thermoplastic resin layer (C) may be one layer or multiple layers.
• the thermoplastic resin layers (C) made of the same material are continuously laminated, they are considered to be one layer.
• the EVOH layer (A) is "A”
• the adhesive layer (B) is "B”
• the thermoplastic resin layer (C) is "C”
• the multilayer film is considered to be a C/B/A multilayer film
• the average thickness of each layer of the thermoplastic resin layer (C) is the sum of the average thicknesses of the three layers.
• each layer is considered to be an independent layer.
• the multilayer film for vacuum insulation materials of the present invention has an EVOH layer (A), an adhesive layer (B) and a thermoplastic resin layer (C) in this order, and preferably has a configuration in which the EVOH layer (A), the adhesive layer (B) and the thermoplastic resin layer (C) are directly laminated in this order.
• the layer configuration of the multilayer film of the present invention include, for example, C/B/A, C/B/A/B/A, A/B/C/B/A, C/B/A/B/C/B/A, C/C/B/A, C/C/C/B/A, etc., and among them, C/B/A, C/C/B/A, and C/C/C/B/A are preferred from the viewpoint of industrial productivity.
• C/B/A, C/C/B/A, and C/C/C/B/A are preferred from the viewpoint of industrial productivity.
• the multilayer film has multiple thermoplastic resin layers (C)
• an embodiment in which an HDPE layer, an LDPE layer or an LLDPE layer, and a layer containing HDPE and LDPE or LLDPE are laminated is preferred.
• the overall average thickness of the multilayer film of the present invention can be appropriately set depending on the application of the vacuum insulation material.
• the overall average thickness is preferably 10 ⁇ m or more, more preferably 15 ⁇ m or more, and even more preferably 20 ⁇ m or more. When the overall average thickness is 10 ⁇ m or more, industrial productivity and mechanical properties tend to improve.
• the overall average thickness is preferably 300 ⁇ m or less, more preferably 150 ⁇ m or less, even more preferably 100 ⁇ m or less, and particularly preferably 50 ⁇ m or less. When the overall average thickness is 300 ⁇ m or less, industrial productivity and economic efficiency tend to improve.
• the overall average thickness of the multilayer film means the average thickness after stretching.
• the method for producing the multilayer film of the present invention is not particularly limited, but a conventional co-extrusion method in which each resin is extruded from a separate die or a common die and laminated is preferred.
• a co-extrusion method it is possible to achieve a high level of balance between film properties such as gas barrier properties and flexibility, processability (reduction of film thickness unevenness), and economy (easiness to achieve the desired configuration (e.g., thinning of the EVOH layer (A)) with fewer steps). Therefore, it is preferable that the multilayer film of the present invention includes a configuration in which the EVOH layer (A), the adhesive layer (B), and the thermoplastic resin layer (C) are co-extruded.
• co-extrusion methods include co-extrusion cast molding, co-extrusion inflation molding, and co-extrusion coat molding, and among these, inflation molding using a circular die is preferred. Inflation molding is also preferred in terms of cost.
• inflation molding is used to produce the multilayer film of the present invention, a known means can be used as the inflation molding method.
• the multilayer film of the present invention is stretched at least uniaxially by 3 times or more and 12 times or less. If the multilayer film of the present invention is stretched less than 3 times, the thickness unevenness due to stretching tends to occur and the gas barrier property tends to decrease. On the other hand, if the multilayer film of the present invention is stretched more than 12 times, the film surface after stretching tends to deteriorate.
• the multilayer film of the present invention is preferably stretched at least uniaxially by 4 times or more, more preferably by 5 times or more. In addition, the multilayer film of the present invention is preferably stretched at least uniaxially by 10 times or less, more preferably by 8 times or less.
• the multilayer film of the present invention may be stretched uniaxially or biaxially, but is preferably stretched uniaxially, and is particularly preferably stretched uniaxially in the longitudinal direction (MD direction). In this case, it is preferable that the film is not substantially stretched in the width direction (TD direction).
• the multilayer film of the present invention is biaxially stretched, it is preferably stretched mainly in the longitudinal direction (MD direction), and the ratio (MD/TD) of the stretching ratio in the longitudinal direction (MD direction) to the stretching ratio in the transverse direction (TD direction) is preferably 3 or more, more preferably 4 or more, and even more preferably 5 or more.
• the ratio of the stretching ratios (MD/TD) may be 12 or less.
• the stretching method for the multilayer film is not particularly limited, and examples thereof include tenter stretching, tubular stretching, and roll stretching.
• uniaxial stretching roll stretching and the like can be used.
• the temperature range for uniaxial stretching is generally 50 to 130°C.
• biaxial stretching tenter stretching and the like can be used.
• simultaneous biaxial stretching a temperature range of 70 to 100°C is used to obtain a biaxially stretched film with less stretch unevenness.
• sequential biaxial stretching a temperature range of 70 to 100°C is used for stretching in the machine direction (MD direction), and a temperature range of 80 to 120°C is used for stretching in the width direction (TD direction), to obtain a biaxially stretched film with less stretch unevenness.
• the puncture strength of the multilayer film measured in accordance with JIS Z 1707:2019 is preferably 2.7 N or more, and more preferably 3.3 N or more. If the puncture strength is 2.7 N or more, the defective rate of the vacuum insulation material tends to decrease. The puncture strength may be 12 N or less.
• the vapor-deposited multilayer film for vacuum insulation materials of the present invention has an inorganic vapor-deposited layer (D) on the surface of the EVOH layer (A) opposite to the surface on which the adhesive layer (B) is laminated.
• the inorganic vapor deposition layer (D) is a layer having a barrier property against oxygen and water vapor.
• the vapor-deposited multilayer film of the present invention has good gas barrier properties and can be maintained in a high vacuum state for a long period of time.
• the inorganic vapor deposition layer (D) can be formed by vapor deposition of an inorganic material, and is preferably laminated directly on the surface of the EVOH layer (A). The adhesion of the layer (D) tends to be further improved.
• the inorganic substance contained as the main component is a metal (e.g., aluminum), a metal oxide (e.g., silicon oxide, aluminum oxide), a metal nitride (e.g., , silicon nitride), metal nitride oxides (e.g., silicon oxynitride), and metal carbonitrides (e.g., silicon carbonitride).
• a metal e.g., aluminum
• a metal oxide e.g., silicon oxide, aluminum oxide
• a metal nitride e.g., silicon nitride
• metal nitride oxides e.g., silicon oxynitride
• metal carbonitrides e.g., silicon carbonitride
• the inorganic vapor deposition layer (D) is preferably silicon nitride from the viewpoint of industrial productivity, and the inorganic vapor deposition layer (D) containing aluminum as the main component is more preferable.
• the inorganic vapor deposition layer (D) containing aluminum as a main component preferably has an aluminum oxide layer (D1) and an aluminum layer (D2) successively arranged in this order from the surface side in contact with the EVOH layer (A), and in an elemental analysis of the aluminum oxide layer (D1) in the depth direction, the maximum molar ratio of oxygen element to aluminum element (O/Al) MAX measured with a scanning X-ray photoelectron spectroscopy is 0.5 or more and 2.0 or less, and in an elemental analysis of the aluminum layer (D2) in the depth direction, the minimum molar ratio of oxygen element to aluminum element (O/Al) MIN measured with a scanning X-ray photoelectron spectroscopy is less than 0.5.
• the elemental composition is usually not constant in each of the aluminum oxide layer (D1) and the aluminum layer (D2).
• the content ratio of oxygen element gradually decreases from the aluminum oxide layer (D1) to the aluminum layer (D2).
• the content ratio of oxygen element in the intermediate layer portion (aluminum layer (D2)) is relatively low.
• the content ratio of oxygen element is relatively high in the region (aluminum oxide layer (D1)) of a predetermined thickness from the surface in contact with the EVOH layer (A) compared with the intermediate layer portion (aluminum layer (D2)).
• an aluminum oxide layer (D3) having a relatively high content ratio of oxygen element compared with the intermediate layer portion (aluminum layer (D2)) may be formed in the region of a predetermined thickness from the surface of the inorganic vapor deposition layer (D) opposite to the surface in contact with the EVOH layer (A).
• the maximum molar ratio (O/Al) MAX of oxygen element to aluminum element in the aluminum oxide layer (D1) and the molar ratio (O/Al) of oxygen element to aluminum element in the aluminum oxide layer (D3) may be larger.
• the maximum molar ratio (O/Al) MAX of oxygen element to aluminum element in the aluminum oxide layer (D1) is the maximum value in the aluminum oxide layer (D1) and does not necessarily coincide with the maximum value in the inorganic vapor deposition layer (D).
• the maximum molar ratio (O/Al) MAX of oxygen element to aluminum element measured by a scanning X-ray photoelectron spectrometer is 0.5 to 2.0, preferably 0.8 to 1.8, more preferably 1.1 to 1.5.
• the adhesion of the inorganic vapor deposition layer (D) to the EVOH layer (A) tends to be further improved, and the defective rate of the vacuum insulation material before and after bending tends to be further reduced.
• the bending storage property of the vacuum insulation material tends to be further improved.
• the position at which the maximum molar ratio of oxygen to aluminum (O/Al) MAX is observed in elemental analysis of the aluminum oxide layer (D1) in the depth direction is preferably in the range of 0 nm or more and 20 nm or less, and more preferably in the range of 0 nm or more and 15 nm or less, from the surface in contact with the EVOH layer (A).
• the minimum molar ratio (O/Al) MIN of the oxygen element to the aluminum element measured by a scanning X-ray photoelectron spectrometer is less than 0.5, preferably 0.001 or more and less than 0.5, more preferably 0.003 or more and less than 0.2, even more preferably 0.005 or more and less than 0.10, and even more preferably 0.01 or more and less than 0.06.
• the minimum molar ratio (O/Al) MIN of the oxygen element (O) to the aluminum element (Al) in the aluminum layer (D2) is in the above range, the gas barrier property of the vapor deposition multilayer film tends to be improved. In addition, the defective rate of the vacuum insulation material before and after bending tends to be further reduced. In addition, the bending storage property of the vacuum insulation material tends to be further improved.
• the average thickness of the inorganic vapor deposition layer (D) is preferably 30 nm or more and 100 nm or less.
• the lower limit of the average thickness is more preferably 35 nm or more, and even more preferably 45 nm or more.
• the upper limit of the average thickness of the inorganic vapor deposition layer (D) is more preferably 90 nm or less, and may be 80 nm or less, 70 nm or less, or 60 nm or less.
• the method for forming the inorganic vapor deposition layer (D) is not particularly limited, and examples thereof include physical vapor deposition methods such as vacuum vapor deposition (e.g., resistance heating vapor deposition, electron beam vapor deposition, molecular beam epitaxy, etc.), sputtering, and ion plating; and chemical vapor deposition methods such as thermal chemical vapor deposition (e.g., catalytic chemical vapor deposition), photochemical vapor deposition, plasma chemical vapor deposition (e.g., capacitively coupled plasma, inductively coupled plasma, surface wave plasma, electron cyclotron resonance, dual magnetron, atomic layer deposition, etc.), and metalorganic chemical vapor deposition.
• physical vapor deposition methods such as vacuum vapor deposition (e.g., resistance heating vapor deposition, electron beam vapor deposition, molecular beam epitaxy, etc.), sputtering, and ion plating
• chemical vapor deposition methods such as thermal chemical vapor deposition (
• the inorganic vapor deposition layer (D) having the aluminum oxide layer (D1) and the aluminum layer (D2) can be effectively provided, for example, by using a vacuum vapor deposition method.
• a vacuum vapor deposition method For example, when performing vacuum vapor deposition of aluminum on the surface of the EVOH layer (A) of the multilayer film, the vapor deposition is performed while supplying a small amount of oxygen gas toward the multilayer film.
• oxygen gas toward the multilayer film.
• aluminum elements are laminated in the form of aluminum oxide on the surface of the EVOH layer (A), and an aluminum oxide layer (D1) is formed.
• the maximum value (O/Al) MAX of the molar ratio of oxygen element (O) to aluminum element (Al) in the aluminum oxide layer (D1) can be controlled by the supply amount of oxygen gas blown onto the multilayer film, etc.
• the supply amount of oxygen gas to the multilayer film can be, for example, 20 mL/min or more and 180 mL/min or less. However, the suitable supply amount of oxygen gas is appropriately adjusted depending on the vapor deposition rate of aluminum, etc.
• an oxide film is usually formed on the surface of the inorganic vapor-deposited layer (D) by exposure to an air atmosphere, and this oxide film can become an aluminum oxide layer (D3).
• the surface of the EVOH layer (A) may be plasma-treated.
• the plasma treatment may be performed by a known method, and atmospheric pressure plasma treatment is preferred.
• discharge gases used in atmospheric pressure plasma treatment include nitrogen gas, helium, neon, argon, krypton, xenon, and radon.
• the layer structure of the vapor-deposited multilayer film is not particularly limited as long as an inorganic vapor-deposited layer (D) is provided on the surface of EVOH (A) opposite to the surface on which the adhesive layer (B) is laminated, and examples thereof include C/B/A/D, C/B/A/B/A/D, A/B/C/B/A/D, C/B/A/B/C/B/A/D, C/C/B/A/D, C/C/C/B/A/D, etc. Among these, C/B/A/D, C/C/B/A/D, and C/C/C/B/A/D are preferred from the viewpoint of industrial productivity.
• the overall average thickness of the vapor-deposited multilayer film can be set appropriately depending on the application of the vacuum insulation material.
• the overall average thickness is preferably 10 ⁇ m or more, more preferably 15 ⁇ m or more, and even more preferably 20 ⁇ m or more.
• An overall average thickness of 10 ⁇ m or more tends to improve industrial productivity and mechanical properties.
• the overall average thickness is preferably 300 ⁇ m or less, more preferably 150 ⁇ m or less, even more preferably 100 ⁇ m or less, and particularly preferably 50 ⁇ m or less.
• An overall average thickness of 300 ⁇ m or less tends to improve industrial productivity and economic efficiency.
• the multilayer film or the vapor-deposited multilayer film may be further laminated with a thermoplastic resin layer (E) to be used as a multilayer structure for vacuum insulation materials.
• a thermoplastic resin layer (E) to be used as a multilayer structure for vacuum insulation materials. This can impart properties such as heat sealability and mechanical strength according to the type of thermoplastic resin constituting the thermoplastic resin (E) layer.
• the thermoplastic resin layer (E) is laminated directly or via another layer on at least one surface of the multilayer film or the vapor-deposited multilayer film.
• thermoplastic resin layer (E) examples of the thermoplastic resin used in the thermoplastic resin layer (E) include polyethylene such as linear low density polyethylene, low density polyethylene, very low density polyethylene, medium density polyethylene, and high density polyethylene, and ethylene-vinyl acetate copolymer.
• polystyrene-ethylene-propylene (block or random) copolymer such as homopolymers or copolymers of olefins such as polypentene, or polyolefins graft-modified with unsaturated carboxylic acids or their esters; polyesters; polyamides (including copolymerized polyamides); polyvinyl chloride; polyvinylidene chloride;
• the polyether polyether polyol include acrylic resins, polystyrene, polyvinyl esters, polyester elastomers, polyurethane elastomers, chlorinated polystyrene, chlorinated polypropylene, aromatic polyketones or aliphatic polyketones, and polyalcohols
• thermoplastic resin layer (E) contains at least one selected from the group consisting of polyamide, polyester, polyethylene, and polypropylene, and it is preferable that the thermoplastic resin layer (E) contains at least one selected from the group consisting of polyamide, polyester, and polyethylene. More preferred.
• the content of the thermoplastic resin in the thermoplastic resin layer (E) is preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, and particularly preferably 98% by mass or more, and the thermoplastic resin layer (E) may be substantially composed of only the thermoplastic resin, or may be composed of only the thermoplastic resin.
• thermoplastic resin layer (E) is a polyolefin layer containing polyolefin
• these layers may be unstretched or stretched.
• these layers are preferably unstretched from the viewpoint of good heat sealability.
• the outermost layer is a polyolefin layer when formed into a bag shape
• these layers are preferably stretched from the viewpoint of good mechanical strength.
• the polyolefin layer used as the thermoplastic resin layer (E) a polyethylene layer containing polyethylene and a polypropylene layer containing polypropylene are preferred.
• the polyamide layer is preferably at least one outermost layer in the multilayer structure.
• the layer that becomes the outermost layer when formed into a bag shape may be a polyamide layer.
• one outermost layer may be a polyethylene layer, and the other outermost layer may be a polyamide layer.
• the polyamide layer may be a non-stretched layer or a stretched layer.
• thermoplastic resin layer (E) may be laminated directly to the multilayer film or the vapor-deposited multilayer film, or may be laminated via another layer.
• the multilayer structure may have an adhesive layer between the multilayer film or the vapor-deposited multilayer film and the thermoplastic resin layer (E).
• the adhesive layer may be a layer made of a curing adhesive (such as a two-component reactive polyurethane adhesive).
• the average thickness of the adhesive layer is preferably 0.1 ⁇ m or more and 10 ⁇ m or less, more preferably 0.3 ⁇ m or more and 5 ⁇ m or less, and even more preferably 0.5 ⁇ m or more and 3 ⁇ m or less.
• the average thickness per layer of the thermoplastic resin layer (E) is preferably 5 ⁇ m or more, more preferably 10 ⁇ m or more, even more preferably 15 ⁇ m or more, and may be 20 ⁇ m or more, 30 ⁇ m or more, or 40 ⁇ m or more.
• the upper limit of the average thickness per layer of the thermoplastic resin layer (E) is preferably 200 ⁇ m or less, more preferably 100 ⁇ m or less, and may be 60 ⁇ m or less. When the average thickness per layer of the thermoplastic resin layer (E) is within the above range, the function required of the thermoplastic resin layer (E) tends to be exhibited. In addition, when the average thickness per layer of the thermoplastic resin layer (E) is equal to or less than the above upper limit, it is possible to reduce the thickness of the multilayer structure.
• the multilayer structure of the present invention may further include another inorganic vapor deposition layer laminated to the multilayer film or the vapor deposition multilayer film directly or via another layer, in addition to the inorganic vapor deposition layer (D) of the vapor deposition multilayer film.
• Such an inorganic vapor deposition layer may be provided, for example, by using a thermoplastic resin layer (E) as a substrate. That is, it may be provided by laminating another vapor deposition film obtained by vapor depositing an inorganic substance on a resin film forming the thermoplastic resin layer (E) with the multilayer film or the vapor deposition multilayer film.
• inorganic substances constituting such an inorganic vapor deposition layer include those mentioned above as constituting the inorganic vapor deposition layer (D).
• PET polyethylene terephthalate
• inorganic vapor deposition layer (D) is preferably laminated.
• the multilayer structure of the present invention may include two or more of the multilayer films or the vapor-deposited multilayer films.
• the multilayer films or the vapor-deposited multilayer films may be the same or different.
• the multilayer structure of the present invention may have layers other than the multilayer film, the vapor-deposited multilayer film, the thermoplastic resin layer (E), the adhesive layer, and the other inorganic vapor-deposited layer.
• the other layers include a paper layer and a metal foil layer.
• the layer structure of the multilayer structure of the present invention may be, for example, ⁇ MLF//PO ⁇ MLF//MLF/PO ⁇ PO//MLF//PO ⁇ PO//MLF//PO//PO ⁇ PA//MLF//PO ⁇ PO//MLF//PO ⁇ PA//MLF//PA//PO ⁇ PO//MLF///PO ⁇ PA//MLF///PO ⁇ PET//MLF//PO ⁇ M-PET//M-PET//MLF//PO ⁇ PA///PET//MLF//PO ⁇ PA///M-PET///MLF//PO ⁇ PA///M-PET///MLF/PO ⁇ PA///VLF//M-PET///PO ⁇ PA//M-PET///VLF//M-PET///PO ⁇ M-PET///VLF//M-PET//
• MLF refers to the multilayer film or the vapor-deposited multilayer film
• PO refers to the polyolefin layer
• PA refers to the polyamide layer
• PET refers to the PET layer
• M-PET refers to the PET layer with inorganic vapor deposition.
• a structure in which another layer is disposed at any position is also an example of the multilayer structure of the present invention.
• the orientation of the multilayer film or the vapor-deposited multilayer film is not particularly limited.
• the layer structure "MLF//PO" of the multilayer structure (1) above includes a multilayer film having a layer structure of "A/B/C”, it may have a layer structure of "A/B/C//PO” or a layer structure of "C/B/A//PO", but when it has an inorganic vapor deposition layer (D), it is preferable that "MLF//PO" has a layer structure of "D/A/B/C//PO".
• the M-PET may have a structure of either "inorganic vapor deposition layer/PET” or “PET/inorganic vapor deposition layer,” but it is preferable for the inorganic vapor deposition layer to face the "MLF" side, and the inorganic vapor deposition layer of the M-PET is preferably an aluminum oxide layer or a silicon oxide layer.
• the average thickness of the multilayer structure of the present invention (average thickness of the entire multilayer structure) is preferably 10 ⁇ m or more, and may be 20 ⁇ m or more, 30 ⁇ m or more, or 50 ⁇ m or more.
• the average thickness of the multilayer structure is preferably 1,000 ⁇ m or less, and may be 500 ⁇ m or less, 300 ⁇ m or less, 200 ⁇ m or less, or 100 ⁇ m or less.
• a multilayer structure can be obtained by laminating a resin film forming a thermoplastic resin layer (E), the other vapor-deposited film, etc., to the multilayer film or the vapor-deposited multilayer film by a known means such as dry lamination.
• a multilayer structure can be obtained by laminating a thermoplastic resin layer (E), etc., to the multilayer film or the vapor-deposited multilayer film by, for example, melt extrusion.
• the vacuum packaging bag of the present invention includes a packaging bag including the multilayer structure for vacuum insulation material of the present invention, and the inside of the packaging bag is decompressed.
• the vacuum packaging bag is used as an exterior material for a vacuum insulation material.
• the multilayer structure used for the vacuum packaging bag is preferably configured to use a polyethylene layer as the innermost layer as the thermoplastic resin layer (E). In this case, it is preferable that the polyethylene layer is not stretched.
• the multilayer structure is configured to include a polyamide layer as the thermoplastic resin layer (E).
• the inorganic vapor deposition layer (D) is arranged outside the EVOH layer (A).
• the vacuum packaging bag (outer packaging material) is formed, for example, by heat sealing the multilayer structure.
• the vacuum insulation material of the present invention includes the vacuum packaging bag and a core material disposed therein.
• the vacuum packaging bag is also called an outer packaging material.
• the vacuum insulation material is used for applications requiring cold or warm insulation.
• Examples of the core material include glass fiber and polyurethane foam.
• the core material is sealed in a vacuum state in the vacuum packaging bag (outer packaging material).
• the vacuum insulation material of the present invention suppresses the deterioration of gas barrier properties after bending processing and bending storage, and can maintain a high insulating effect for a long period of time.
• This vacuum insulation material can be used as an insulation material for home appliances such as refrigerators, hot water supply equipment, and rice cookers; residential insulation material used in walls, ceilings, attics, floors, etc.; vehicle roofing material; and insulation panels for vending machines, etc.
• the measurement was performed under the following conditions: X-ray source was AlK ⁇ (1486.6 eV), X-ray beam diameter was 100 ⁇ m ⁇ (25 W, 15 kV), measurement range was 300 ⁇ m horizontal ⁇ 300 ⁇ m vertical, signal capture angle was 45°, and vacuum degree was 1 ⁇ 10-6 Pa.
• the molar ratio of oxygen element to aluminum element at the measurement point where the molar ratio of oxygen element observed on the EVOH layer (A) side (i.e., observed in the aluminum oxide layer (D1)) was maximum was defined as (O/Al) MAX
• the molar ratio of oxygen element to aluminum element at the measurement point where the molar ratio of oxygen element was minimum was defined as (O/Al) MIN .
• the puncture strength was measured according to JIS Z 1707: 2019. Specifically, the multilayer films obtained in the examples and comparative examples were conditioned for one week under conditions of 23°C/50% RH, then cut into a circle with a diameter of 10 cm, the test piece was fixed using a jig, and a semicircular needle with a diameter of 1.0 mm and a tip radius of 0.5 mm was pierced at a speed of 50 mm/min using AUTOGRAPH AGS-H (manufactured by Shimadzu Corporation), the maximum stress until the needle penetrated was measured, and the evaluation was performed according to the following criteria.
• C Less than 3.0N 2.7N or more
• D Less than 2.7N
• the evaluation was performed twice, and the average value of the two evaluation results was taken as the thermal conductivity before the test, and the difference before and after the storage test (after the storage test - before the storage test) was calculated and evaluated according to the following criteria.
• D More than 5.0 mW/m.K
• EVOH (a) EVOH1: EVOH (ethylene unit content (Et) 27 mol%, saponification degree 99.99%, MFR 4.0 g/10 min (210° C., 2160 g load), containing 200 ppm of sodium, 10 ppm of phosphoric acid, 500 ppm of boric acid, and 200 ppm of acetic acid)
• EVOH3 EVOH (ethylene unit content (Et) 24 mol%, saponification degree 99.99%, MFR 2.2 g/10 min (210° C., 2160 g load), containing 200 ppm of sodium, 10 ppm of phosphoric
• MAhPP "Admer (trademark) QF500” (maleic anhydride modified polypropylene, manufactured by Mitsui Chemicals, Inc., MFR (210°C, under a load of 2160 g) 2.2 g/10 min, density 0.91 g/cm 3 )
• PE "Lumicene (trademark) Supertough 40ST05” (polyethylene, manufactured by Total, MFR (210°C, under a load of 2160 g) 0.6 g/10 min), density 0.94 g/cm 3 ).
• ⁇ Thermoplastic resin (c') PP "Novatec (trademark) FL203D” (manufactured by Japan Polypropylene Corporation, MFR (210°C, under a load of 2160 g) 2.0 g/10 min), density 0.90 g/cm 3 ).
• VM-PET1510 aluminum-deposited PET film (average thickness 12 ⁇ m), manufactured by Toray Industries, Inc.
• OPA "EMBLEM (registered trademark) ONM15” (biaxially oriented polyamide film (average thickness 15 ⁇ m), manufactured by Unitika Ltd.)
• LLDPE "Unilux (registered trademark) LS760C” (LLDPE film (average thickness 50 ⁇ m) manufactured by Idemitsu Unitech Co., Ltd.)
• thermoplastic resin layer (C) A cylindrical multilayer film was produced using an inflation extrusion machine under the following conditions, using EVOH1 as the material for the EVOH layer (A), MAhPE as the material for the adhesive layer (B), and PE as the material for the thermoplastic resin layer (C).
• the thermoplastic resin (C) layer was laminated in three layers with an average thickness of 50 ⁇ m, resulting in one thermoplastic resin (C) layer with an average thickness of 150 ⁇ m.
• ⁇ Multilayer film manufacturing conditions> Layer structure of the multilayer film: [Inner surface side] EVOH layer (A) / adhesive layer (B) / thermoplastic resin layer (C) 18 ⁇ m / 6 ⁇ m / 150 ⁇ m (total average thickness 174 ⁇ m) Equipment: Five-type, five-layer inflation extrusion molding machine (manufactured by Dr Collin) Die temperature: 220°C Blow-up ratio: 2.7 Take-off speed: 4 m/min Film folding width: 25cm ⁇ EVOH Layer (A) Extruder Conditions> Extruder: 30 ⁇ single screw extruder (manufactured by Dr Collin) Rotation speed: 24 rpm.
• ⁇ Conditions of extruder for adhesive layer B>
• Extrusion temperature: feeding section/compression section/metering section 170°C/190°C/210°C
• Extrusion temperature: feeding section/compression section/metering section 170°C/190°C/210°C.
• the puncture strength of the obtained stretched multilayer film was measured according to the method described in the evaluation method (3) above. The results are shown in Table 1.
• An aluminum vapor deposition layer was formed as an inorganic vapor deposition layer (D) on the resulting stretched multilayer film using the "EWA-105" winding vacuum deposition device manufactured by Japan Vacuum Engineering Co., Ltd., which has a transport chamber and a vapor deposition chamber, in the following manner.
• the "EWA-105" has an unwinder and winder on the transport chamber side, and inside the vapor deposition chamber there is a crucible for heating the aluminum and a cooling can which cools the film as it is transported, and the film is transported along the cooling can.
• the cooling can was cooled to -30°C, and the resulting stretched multilayer film was positioned so that a vapor deposition layer was formed on the EVOH layer (A) side, and then transported at a transport speed of 150 m/min. Furthermore, a nozzle was installed in the deposition chamber to blow oxygen directly onto the stretched multilayer film before deposition (nozzle gap 2 mm, nozzle width 21 cm, film-nozzle distance 2 cm, angle to film 30 degrees), and aluminum was vacuum-deposited while blowing oxygen at 80 mL/min, producing a vapor-deposited multilayer film in which an aluminum vapor-deposited layer with an average thickness of 50 nm was formed on the EVOH layer (A) of the stretched multilayer film.
• the average thickness of the aluminum vapor-deposited layer was adjusted by appropriately controlling the voltage applied to the crucible.
• the molar ratio of oxygen element to aluminum element (O/Al) was calculated according to the method described in the above evaluation method (2). The results are shown in Table 2.
• a two-component urethane adhesive (TakelacTM A-520 and TakenateTM A-50, manufactured by Mitsui Chemicals, Inc.) was applied to the aluminum vapor deposition layer side of VM-PET to an average thickness of 1.0 ⁇ m after drying and dried to form an adhesive layer (Ad), which was then laminated to the aluminum vapor deposition layer side of the resulting multilayer film to produce a laminate (PET-VM/Ad/aluminum vapor deposition layer/EVOH layer (A)/adhesive layer (B)/thermoplastic resin layer (C)).
• An adhesive layer (average thickness 1.0 ⁇ m) was also formed on one side of the OPA and LLDPE in the same manner as above, and OPA was laminated on the PET side and LLDPE was laminated on the thermoplastic resin layer (C) side to produce a multilayer structure (OPA/Ad/PET-VM/Ad/aluminum vapor deposition layer/EVOH layer (A)/adhesive layer (B)/thermoplastic resin layer (C)/Ad/LLDPE).
• the obtained multilayer structure was evaluated according to the methods described in the above evaluation methods (4) to (6). The results are shown in Table 1.
• Example 2 to 5 In the preparation of the multilayer film, a multilayer film, a vapor-deposited multilayer film, and a multilayer structure were prepared and evaluated in the same manner as in Example 1, except that the average thickness of the EVOH layer (A) was changed as shown in Table 1 by adjusting the rotation speed of the extruder for the EVOH layer (A). The results are shown in Table 1. The evaluation by the above evaluation method (2) was not performed.
• Example 6 and 7 A multilayer film, a vapor-deposited multilayer film, and a multilayer structure were produced and evaluated in the same manner as in Example 2, except that the type of EVOH was changed as shown in Table 1. The results are shown in Table 1. The evaluation by the above evaluation method (2) was not performed.
• Example 1 A multilayer film, a vapor-deposited multilayer film, and a multilayer structure were produced and evaluated in the same manner as in Example 3, except that the type of EVOH was changed as shown in Table 1. The results are shown in Table 1. The evaluation by the above evaluation method (2) was not performed.
• Example 3 A multilayer film, a vapor-deposited multilayer film, and a multilayer structure were produced and evaluated in the same manner as in Example 1, except that the materials of the adhesive layer (B) and the thermoplastic resin layer (C) were changed as shown in Table 1. The results are shown in Table 1. The evaluation by the above evaluation method (2) was not performed.
• Comparative Example 4 A multilayer film, a vapor-deposited multilayer film, and a multilayer structure were produced and evaluated in the same manner as in Comparative Example 3, except that the material of the EVOH layer (A) was changed as shown in Table 1, and the rotation speeds of the EVOH layer (A) extruder and the thermoplastic resin layer (C) extruders 1 to 3 were adjusted to change the average thicknesses of the EVOH layer (A) and the thermoplastic resin layer (C) as shown in Table 1. The results are shown in Table 1. The evaluation by the above evaluation method (2) was not performed.
• Example 8 to 11 A multilayer film, a deposited multilayer film, and a multilayer structure were produced and evaluated in the same manner as in Example 1, except that the amount of oxygen supplied during deposition was changed as shown in Table 2. The results are shown in Table 2.

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  • 2024-06-21 WO PCT/JP2024/022677 patent/WO2024262628A1/ja not_active Ceased
  • 2024-06-21 CN CN202480052853.1A patent/CN121712648A/zh active Pending

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