JP6841008B2 - Polyethylene resin for extrusion lamination, foam laminate using it, foam laminate - Google Patents

Description

The present invention relates to a polyethylene resin for extrusion lamination, which is highly productive and exhibits good heat insulating properties and a foamed appearance, and a foamed laminate and a foamed laminate using the same.

Conventionally, synthetic resins, especially those in which polystyrene is foamed, are often used as containers having heat insulating properties. However, expanded polystyrene containers have drawbacks such as a high environmental load at the time of disposal and inferior printability, and alternatives to other materials are being considered. Under such circumstances, a container in which corrugated paper is bonded to the outer peripheral surface of the body of the paper cup to form a heat insulating layer, a container in which a laminate of pulp non-woven fabric and coated paper is bonded to the outer peripheral surface of the body of the paper cup, etc. Has been developed and used.

However, each method has a drawback that it is not easy to process and mold, and the cost is high. Therefore, a technique of laminating a low melting point thermoplastic synthetic resin film on at least one surface of a base material containing water and heating the base material to foam the synthetic resin film unevenly using the water contained in the base material. Was devised (see, for example, Patent Documents 1 to 3). However, in the material thus obtained, the thickness of the foam layer is thin and the heat insulating property is insufficient.

Further, it is composed of a container body member and a bottom plate member, and a high melting point thermoplastic synthetic resin film is laminated on the inner wall surface of the base paper of the container body member and the bottom plate member, and low melting point heat is formed on the outer wall surface of the base paper of the container body member. A heat insulating paper container in which a plastic synthetic resin film is laminated and the low melting point thermoplastic synthetic resin film is heat-treated and foamed has been proposed (see, for example, Patent Document 4).

However, although the heat insulating paper container having a high melting point thermoplastic synthetic resin on the inner wall surface has good heat insulating properties, if the processing speed when laminating the low melting point thermoplastic resin is increased, the foamed appearance deteriorates and the production It was inferior in sex.

Further, as a heat insulating paper container having an excellent foamed appearance, a heat insulating paper container having a foamed layer in which low-density polyethylene having a specific melt mass flow rate is foamed on at least one side of the paper has been proposed (for example, Patent Documents 5 to 6). reference).

However, even if low-density polyethylene in which only the melt mass flow rate is controlled is used, the deterioration of the foamed appearance is not solved when the processing speed at the time of laminating molding is increased, and the productivity is inferior.

Special Publication No. 48-322383 Japanese Unexamined Patent Publication No. 57-110439 Japanese Unexamined Patent Publication No. 2001-270571 Japanese Unexamined Patent Publication No. 2004-558534 Japanese Patent No. 5197983 JP 2015-171794

An object of the present invention is to provide a polyethylene resin for extrusion lamination, which is highly productive and exhibits good heat insulating properties and a foamed appearance, and a foamed laminate and a foamed laminate using the same.

As a result of diligent studies to solve the above problems, the present inventors have made a polyethylene-based resin for extrusion lamination highly productive, and has excellent heat insulating properties and a foamed appearance. He found that he could obtain a body and completed the present invention.

That is, it relates to a polyethylene resin for extrusion lamination that satisfies (i) to (iii).

(I) Melt mass flow rate (MFR) measured by JIS K6922-1 (1997) is 8 g / 10 minutes or more and 50 g / 10 minutes or less. (Ii) Melt tension measured at a temperature of 130 ° C. and a take-up speed of 2 m / min (ii). MS ₁₃₀ ) is 70 mN or more and 150 mN or less (iii) The melt tension (MS ₁₉₀ ) measured at a temperature of 190 ° C. and a take-up speed of 10 m / min is 3 mN or more and 30 mN or less. It relates to a foaming laminate containing at least a layer and a paper substrate layer adjacent thereto.

Further, the present invention relates to a foamed laminate in which the layer (A) of the foamed laminate is foamed.

Hereinafter, the present invention will be described in detail.

The polyethylene-based resin for extrusion lamination of the present invention is at least a low-pressure ethylene homopolymer, a high-pressure low-density polyethylene, an ethylene / α-olefin copolymer, an ethylene / vinyl acetate copolymer, and an ethylene / ethyl acrylate copolymer. , Ethylene / acrylic acid copolymer, ethylene / methacrylic acid copolymer and the like, but it is preferable to contain at least high-pressure low-density polyethylene (a) because it has an excellent foamed appearance.

Such a high pressure method low density polyethylene (a) can be obtained by a conventionally known high pressure method radical polymerization method.

The melt mass flow rate (hereinafter, simply abbreviated as MFR) measured by JIS K6922-1 (1997) of the polyethylene resin for extrusion lamination of the present invention has excellent heat insulating properties and foamed appearance, and therefore is 8 to 50 g / 10 minutes. The range is more preferably 10 to 35 g / 10 minutes, still more preferably 12 to 25 g / 10 minutes. If the MFR of the polyethylene resin for extrusion laminating is less than 8 g / 10 minutes, the foamed appearance is inferior, which is not preferable, and if it exceeds 50 g / 10 minutes, the laminating workability is inferior, which is not preferable.

The density (hereinafter, simply abbreviated as density) measured by JIS K6922-1 (1997) of the polyethylene resin for extrusion lamination of the present invention is not particularly limited as long as the object of the present invention is achieved. The range of ^{910 to 930 kg / m 3} is preferable because it is excellent in foamed appearance.

_{The melt tension (hereinafter, simply abbreviated as MS 130} ) measured at a temperature of 130 ° C. and a take-up speed of 2 m / min for the polyethylene-based resin for extrusion lamination of the present invention is in the range of 70 to 150 mN because of its excellent foamed appearance. It is preferably in the range of 80 to 120 mN. _{If the MS 130 of the} polyethylene resin for extrusion lamination is less than 70 mN, it is not preferable because the foamed appearance is inferior, and if it exceeds 150 mN, it is not preferable because the heat insulating property is inferior.

_{Further, the melt tension (hereinafter, simply abbreviated as MS 190} ) measured at a temperature of 190 ° C. and a take-up speed of 10 m / min for the polyethylene resin for extrusion lamination is in the range of 3 to 30 mN because of its excellent foamed appearance, which is more preferable. Is in the range of 5 to 20 mN. _{If the MS 190 of the} polyethylene resin for extrusion laminating is less than 3 mN, it is not preferable because it is inferior in laminating workability, and if it exceeds 30 mN, it is not preferable because it is inferior in foamed appearance.

Further, the ratio of MS _{130 to MS 190 of the} polyethylene resin for extrusion lamination _{(MS 130} / MS ₁₉₀ ) is preferably in the range of 4.0 to 30.0, more preferably 4.0, because it is excellent in foamed appearance. It is in the range of ~ 15.0.

_{The MS 130} and MS ₁₉₀ in the present invention are provided under the condition that a capillary viscometer having a barrel diameter of 9.55 mm is equipped with a die having a length of 8 mm, a diameter of 2.095 mm and an inflow angle of 90 °, and a heat insulating chamber. It is a value measured at an extrusion speed of 10 m / min, a predetermined take-up speed, and a predetermined set temperature.

The swell ratio (hereinafter, simply abbreviated as SR) of the polyethylene resin for extrusion lamination of the present invention measured at 235 ° C. is preferably in the range of 1.40 or more and less than 1.70, more preferably 1 because of its excellent foamed appearance. It is in the range of .45 to 1.65, most preferably 1.45 to 1.60.

This SR uses the melt indexer used in JIS K6922-1 (1997), extrudes the resin filled in the device from the orifice under the conditions of a temperature of 235 ° C and an extrusion rate of 3 g / min, and is installed directly under the orifice. It is obtained by collecting a strand-shaped extrude with a measuring cylinder containing the above isopropanol and _{dividing the strand diameter (D) by the orifice diameter (D 0} ) of the melt indexer.

The polyethylene-based resin for extrusion lamination of the present invention may be blended with another thermoplastic resin, and is preferably a resin composition because it has an excellent foamed appearance.

When the thermoplastic resin is mixed with the polyethylene resin for extrusion lamination of the present invention, it may be a pellet mixture in which pellets of polyethylene tree for extrusion lamination and pellets of thermoplastic resin are mixed in a solid state. A mixture melt-kneaded with a shaft extruder, a twin-screw extruder, a kneader, a vanbury or the like is preferable because a product with stable quality can be obtained. When a melt-kneading device is used, the melting temperature is preferably about 300 ° C., which is the melting point of the polyolefin resin or the thermoplastic resin.

Further, in the polyethylene resin for extrusion lamination of the present invention, if necessary, additives generally used for polyolefin resins such as antioxidants, light stabilizers, antistatic agents, lubricants, antiblocking agents, etc. are added. It may be added as long as the object of the invention is not impaired.

Among these, crystalline thermoplastic resins (b) other than the high-pressure method low-density polyethylene (a) 95 to 99.9 parts by weight and at least the high-pressure method low-density polyethylene (a) are excellent in foamed appearance and productivity. ) Or the polyethylene-based resin (d) containing 0.1 to 5 parts by weight of either the amorphous thermoplastic resin (c) (the total of (a), (b) and (c) is 100 parts by weight). Is preferable.

The MFR of the high-pressure low-density polyethylene (a) contained in the polyethylene-based resin composition (d) is preferably in the range of 8 to 50 g / 10 minutes, more preferably more preferably, because it is excellent in heat insulating properties and foamed appearance. It is in the range of 10 to 35 g / 10 minutes, more preferably 12 to 25 g / 10 minutes.

The density of the high-pressure low-density polyethylene (a) is, heat insulation, because of their excellent foaming appearance, preferably in the range of 910~930kg / ^{m 3,} more preferably in the range of 910~920kg / ^{m 3.}

Since the SR of such high-pressure low-density polyethylene (a) is excellent in foamed appearance, it is preferably in the range of 1.40 or more and less than 1.70, more preferably 1.45 to 1.65, and most preferably 1. It is in the range of 45 to 1.60.

The melting temperature of the crystalline thermoplastic resin (b) contained in the polyethylene-based resin composition (e) as measured by JIS K7121 (2012) is preferably in the range of 125 to 300 ° C., and is excellent in foamed appearance. The range of 200 ° C. is more preferable, and the range of 150 to 180 ° C. is most preferable.

Such a crystalline thermoplastic resin (b) is not particularly limited as long as the object of the present invention is achieved, and a polyethylene resin, a polypropylene resin, a poly (4-methylpentene), an ethylene / vinyl alcohol copolymer, and the like. Polyvinyl alcohol, saponified ethylene / vinyl acetate copolymer, polyester resin, polyamide resin, polyacetal resin such as polyoxymethylene, liquid crystal polymer such as polycondensate of ethylene terephthalate and parahydroxybenzoic acid, polyvinylidene fluoride, etc. Examples thereof include fluororesins, polylactic acid, and polyglycolic acid. Among these, polypropylene-based resins, poly (4-methyl-1-pentene), ethylene / vinyl alcohol copolymers, polyester-based resins, and polyamide-based resins are preferable because of their excellent foaming performance.

Such a polypropene-based resin is not particularly limited, and is a propylene homopolymer, ethylene of 50 mol% or less with propylene, or propylene such as 1-butene, 1-hexene, 4-methyl-1-pentene, and 1-octene. A copolymer with other α-olefins can be exemplified. These polypropylene-based resins may be used alone or in combination of two or more.

Such polypropylene resins are available from Prime Polymer Co., Ltd. under the trade names of Prime Polypro and Polyfine, from Japan Polypropylene Corporation under the trade names of Novatec PP, Wintech, and Sumitomo Chemical Co., Ltd. under the trade names of Noblen, Excellen, and SunAllomer. Trade names such as polypropylene and Qualia TM are sold by Co., Ltd.

There are no particular restrictions on poly (4-methyl-1-pentene), and examples thereof include the trade name TPX sold by Mitsui Chemicals, Inc.

The ethylene / vinyl alcohol copolymer is not particularly limited, and an ethylene / vinyl alcohol copolymer or an ethylene / vinyl acetate copolymer saponified product having an ethylene component of 50 mol% or less can be exemplified.

Such ethylene / vinyl alcohol copolymers are sold by Kuraray Co., Ltd. under the trade name EVAL TM, and by Nippon Synthetic Chemical Industry Co., Ltd. under the trade name Soanol TM.

The polyester resin is not particularly limited, and is composed of aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid, ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,6. -Polycondensate of aliphatic diol such as hexanediol, cyclohexanedimethanol, or aromatic diol such as bisphenol A, polyethylene terephthalate which is a polycondensate of terephthalic acid and ethylene glycol, and terephthalic acid and 1,4- Examples thereof include polybutylene terephthalate, which is a polycondensate product with butanediol, and polyethylene naphthalate, which is a polycondensate product of 2,6-naphthalenedicarboxylic acid and ethylene glycol. These aromatic dicarboxylic acids, aliphatic diols, and aromatic diols may be used alone or in combination of two or more.

Such polyester resins include polyethylene terephthalate with the trade name Unitica PET resin from Unitica Co., Ltd., Mitsui Chemicals Co., Ltd. with the trade name Mitsui PETTM, and Teijin Co., Ltd. with the trade name PET resin. Chemical Engineering Plastics Co., Ltd. sells the trade name Novaduran, etc., and Teijin Co., Ltd. sells the trade name Theonex, etc. as polyethylene terephthalate.

The polyamide resin is not particularly limited, and is a ring-opened polymer of ω-amino acids such as ε-caprolactam and ω-laurolactam, and a dicarboxylic acid such as adipic acid, sebacic acid, α / ω / dodecanoic acid, terephthalic acid, and isophthalic acid. Acids and aliphatic diamines such as 1,4-diaminobutane, hexamethylenediamine, nonanediamine, methylpentadiamine, 3,3'-dimethyl4,4'-diaminodicyclohexylmethane, or p-phenylenediamine, m-phenylenediamine, etc. Nylon 6, which is a ring-opening polymer of ε-caprolactam, nylon 12, which is a ring-opening polymer of ω-laurolactam, and a polycondensate of adipic acid and hexamethylenediamine. Nylon 66 and the like can be exemplified. These ω-amino acids, dicarboxylic acids, and aliphatic diamines may be used alone or in combination of two or more.

Such polyamide-based resins are UBE Nylon from Ube Industries, Ltd., Amylon @ 6 Nylon from Toray Co., Ltd., Unitika Nylon 6 from Unitica Co., Ltd., and Toyobo Co., Ltd. Product name Gramide etc. is Nylon 12 from Ube Industries, Ltd. Product name UBERON, Daicel Ebonic Co., Ltd. Product name Daiamide etc., Nylon 66 from Toray Co., Ltd. Product name Amylon @ 66 Nylon, Unitika Co., Ltd. ) Selles the trade name Unitica Nylon 66, and Toyobo Co., Ltd. sells the trade name glamid.

The glass transition temperature (hereinafter, simply abbreviated as Tg) of the amorphous thermoplastic resin (c) contained in the polyethylene-based resin composition (e) measured by JIS K7121 (2012) is in the range of 125 to 300 ° C. The range of 145 to 200 ° C. is preferable, and the range of 150 to 180 ° C. is more preferable, because the foamed appearance is excellent. If the Tg of the amorphous thermoplastic resin (c) is less than 125 ° C., the foamed appearance is inferior, which is not preferable, and if the Tg is more than 300 ° C., the laminating workability is inferior, which is not preferable.

Such an amorphous thermoplastic resin (c) is not particularly limited as long as the object of the present invention is achieved, and is a cycloolefin polymer composed of a cyclic olefin such as norbornene, or a copolymer of ethylene and a cyclic olefin such as norbornene. Ethylenecycloolefin copolymer, polycarbonate, polyarylate, which is a copolymer of bisphenol A and terephthalic acid, polyphenylene ether, modified polyphenylene ether, poly, which is a polymer alloy of polyphenylene ether and polystyrene (including impact-resistant polystyrene). Examples thereof include vinyl chloride, polyphenylene sulfide, polyether sulfone, polyamide imide, polyether imide, and polyester carbonate. Among these, cycloolefin polymers, cycloolefin copolymers, and polycarbonates are preferable because they have excellent foaming performance.

The cycloolefin polymer is not particularly limited, and is a thermoplastic resin synthesized by ring-opening polymerization of a cyclic olefin such as norbornene or a derivative thereof. For example, the trade name Zeonex from Nippon Zeon Co., Ltd. is JSR Co., Ltd. ), The product name Arton etc. are on sale.

The cycloolefin copolymer is not particularly limited, and is a thermoplastic resin synthesized by copolymerizing a cyclic olefin such as norbornene or a derivative thereof with an olefin such as ethylene or propylene. For example, from Polyplastics Co., Ltd. The trade name TOPAS (manufacturer is Topas Advanced Polymer Inc.) is sold, and the trade name Appel is sold by Mitsui Kagaku Co., Ltd.

Polycarbonate is not particularly limited, and is a thermoplastic resin synthesized from bisphenol A and phosgen or diphenyl carbonate. The trade name is Panlite from Teijin Limited, and the trade name is Upiron, Novalex from Mitsubishi Engineering Plastics Co., Ltd. , Zanter is sold by Idemitsu Kosan Co., Ltd. under the trade name Tafflon.

Other thermoplastic resins may be blended in the resin composition (d) constituting the present invention as long as the present object is achieved.

When the thermoplastic resin is mixed with the resin composition (d) constituting the present invention, it may be a pellet mixture in which the pellets of the resin composition (d) and the pellets of the thermoplastic resin are mixed in a solid state. A mixture melt-kneaded with a single-screw extruder, a twin-screw extruder, a kneader, a Banbury or the like is preferable because a product with stable quality can be obtained. When a melt-kneading device is used, the melting temperature is preferably the glass transition temperature of the amorphous thermoplastic resin (b) or the melting point of the amorphous thermoplastic resin (c) or more and 300 ° C. or lower.

The method for obtaining such a resin composition (d) for extrusion lamination is to solidify pellets of low-density polyethylene (a) and pellets of crystalline thermoplastic resin (b) and / or amorphous thermoplastic resin (c). Although it may be a pellet mixture mixed in a state, a mixture melt-kneaded with a single-screw extruder, a twin-screw extruder, a kneader, a Banbury or the like is preferable because a product having stable quality can be obtained. When a melt-kneading apparatus is used, the melting temperature is preferably about the melting point of the crystalline thermoplastic resin (b) or the glass transition temperature of the amorphous thermoplastic resin to about 340 ° C.

The polyethylene-based resin for extrusion lamination of the present invention is used as a foaming laminate containing at least a layer (A) made of a polyethylene-based resin for extrusion lamination and a paper base material layer adjacent thereto.

The thickness of the layer (A) constituting such an effervescent laminate is not particularly limited as long as the object of the present invention is achieved, but is preferably in the range of 40 to 150 μm because of its excellent effervescent appearance. It is preferably 50 to 120 μm, more preferably 60 to 100 μm.

The paper base material constituting the foaming laminate is not particularly limited, but the basis weight of the paper base material is 150 to 400 g / m ^{2 because the foaming ratio of the polyethylene resin for extrusion lamination can be improved.} Is preferable, and more preferably 250 to 350 g / m ² .

The water content of such a paper base material is not particularly limited, but is preferably ^{15 to 30 g / m 2} and more preferably 20 to 30 g / m 2 because the foaming ratio of the polyethylene resin for extrusion lamination is improved. 30 g / ^{m 2,} and most preferably 20~26g / ^{m 2.}

Such an effervescent laminate can be obtained by extrusion laminating a polyethylene resin for extrusion laminating on a paper base material.

As a method for obtaining a laminate by an extrusion laminating method, various extrusion laminating methods such as a single laminating method, a tandem laminating method, a sandwich laminating method, and a coextrusion laminating method can be exemplified. The temperature of the resin in the extrusion laminating method is preferably in the range of 260 to 350 ° C., and the surface temperature of the cooling roll is preferably in the range of 10 to 50 ° C.

When a laminate is obtained by an extrusion laminating molding method using the polyethylene-based resin composition (d), the temperature of the resin is the melting point of the crystalline thermoplastic resin (b) or the amorphous thermoplastic resin (c). The temperature exceeds, and more preferably the melting point of the crystalline thermoplastic resin (b) or the amorphous thermoplastic resin (c) is in the range of + 20 ° C to 350 ° C.

In such an extrusion laminating process, immediately after the polyethylene resin for extrusion laminating is formed into an extruded layer in a molten state, the base material adhesive surface of the layer is exposed to an oxygen-containing gas or an ozone-containing gas and bonded to the base material. It is preferable to use it because it has excellent adhesiveness to the base material layer. When improving the adhesiveness between the thermoplastic resin and the base material with ozone-containing gas, the amount of ozone gas to be treated is 0.5 mg or more of ozone per ^{1 m 2 of the film made of the thermoplastic resin extruded from the die.} It is preferable to spray.

Further, in the extrusion laminating method in the method of obtaining the laminate for foaming, in order to further improve the adhesiveness between the polyethylene resin for extrusion lamination and the base material layer, the temperature at which the polyethylene resin does not foam, for example, 3 to 60 It can be heat-treated at a temperature of ° C. for 10 hours or more. Further, if necessary, a known surface treatment such as a corona treatment, a frame treatment, or a plasma treatment may be applied to the adhesive surface of the paper base material. Further, if necessary, an anchor coating agent may be applied to the paper substrate.

Further, as a method for obtaining a foamed laminate, in order to obtain excellent heat insulating properties and economic efficiency of the foamed laminate, water is applied to the surface of the paper substrate before laminating the polyethylene resin for extrusion lamination on the paper substrate layer. You may.

The method of applying water is not particularly limited as long as the object of the present invention is achieved, and a method using a roll coating device, a lip coating device, a spray device, a die coating device, a gravure device, a dampening device, or the like is exemplified. be able to. Since the amount of water applied becomes uniform, a method using a dampening device is preferable.

For example, the product name "High Rotor S" from Suzuki Sangyo Co., Ltd., the product name "WEKO Rotor Damping" from Nikka Co., Ltd., and the product name "WEKO Rotor Dampening" from Toki Electronics Co., Ltd. "TSD-3000" is on sale.

The amount of water applied in the present invention is not particularly limited as long as the object of the present invention is achieved, but the foaming ratio of the polyethylene resin for extrusion lamination can be increased, and the paper substrate and the polyethylene resin for extrusion lamination can be increased. ^{The range of 1.5 to 30 g / m 2} is preferable, and the range of 3 to 15 g / m ² is more preferable, because the adhesive strength with the material does not decrease.

Such a laminate for foaming is characterized by containing at least a layer (A) / a paper base material, and is not only composed of only two components of the layer (A) and a paper base material, but also other components. For example, the layer (B) may be included. Specifically, (A) layer / paper base material, (A) layer / (A) layer / paper base material, (A) layer / paper base material / (A) layer, (A) layer / paper base material / (B) layer, (B) layer / paper base material / (A) layer / (B) layer, (A) layer / paper base material / (B) layer / (B) layer, (A) layer / ( A) layer / paper base material / (B) layer and the like are exemplified. The symbol / between the layers indicates that they are adjacent layers.

Examples of the layer (B) include layers formed from synthetic polymer polymers, woven fabrics, non-woven fabrics, metal foils, papers, cellophane and the like. For example, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polyamide resins such as nylon 6 and nylon 66, high density polyethylene, low density polyethylene, linear low density polyethylene, ethylene-ethyl acrylate copolymer, ethylene- Methacrylate copolymer, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polyethylene resin such as ionomer, polypropylene resin, polybutene, acrylic resin, polyvinyl alcohol, polymethylpentene, polyvinyl chloride, Examples thereof include layers formed from synthetic polymer polymers such as polyvinyl chloride, polystyrene, polycarbonate, polyurethane, and cellulose-based resins. Further, these polymer polymer films and sheets may be further subjected to aluminum vapor deposition, alumina vapor deposition, silicon dioxide vapor deposition, or acrylic treatment. Further, these polymer polymer films and sheets may be further printed using urethane-based ink or the like. Examples of the metal foil include aluminum foil and copper foil, and examples of papers include kraft paper, high-quality paper, stretched paper, glassin paper, and paperboard such as cup base paper and printing paper base paper.

Among these, since it is excellent in heat insulating property and foamed appearance, at least the (A) layer made of polyethylene resin for extrusion lamination, the paper base material, and the (B) layer made of polyethylene resin (h) are laminated in this order. It is preferable to use a laminate for use.

Such a polyethylene-based resin (h) is an ethylene homopolymer, an ethylene / α-olefin copolymer, or a composition thereof, and the form of the molecular chain thereof may be linear and has branches. You may.

The density of the polyethylene resin (h) is thermally insulating, due to excellent stability of the foam, preferably in the range of 930~970kg / ^{m 3,} more preferably from 935~970kg / ^{m 3,} most It is preferably in the range of 945 to 965 kg / m ^3.

Examples of the ethylene homopolymer include medium- and low-pressure ethylene homopolymers and high-pressure low-density polyethylene. Medium / Low Pressure Method The ethylene homopolymer can be obtained by a conventionally known medium / low pressure ion polymerization method. Further, the high-pressure method low-density polyethylene can be obtained by a conventionally known high-pressure radical polymerization method.

Examples of the α-olefin used for the ethylene / α-olefin copolymer include propylene, 1-butene, 4-methyl-1-pentene, 3-methyl-1-butene, 1-pentene, 1-hexene and 1-hexene. Examples thereof include 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, and one or more of these are used.

The method for obtaining the ethylene / α-olefin copolymer is not particularly limited, and examples thereof include high / medium / low pressure ion polymerization methods using a Ziegler-Natta catalyst, a Phillips catalyst, and a metallocene catalyst. Such a copolymer can be conveniently selected from commercially available products.

Among these, since it is excellent in laminate moldability, the density is 930 to 980 kg / m ³ , and it is medium or high, which is composed of at least one of an ethylene / α-olefin copolymer and a medium / low pressure method ethylene homopolymer. High-density polyethylene (j) 90 to 10 parts by weight, MFR 1 to 20 g / 10 minutes, SR 1.50 to 2.20, high-pressure method low-density polyethylene (k) 90 to 10 parts by weight ((j)) The total of k) is preferably an ethylene resin composition (l) containing 100 parts by weight).

The medium / high density polyethylene is an ethylene copolymer obtained by a conventionally known medium / low pressure ion polymerization method, ethylene obtained by a high / medium / low pressure ion polymerization method using a Ziegler-Natta catalyst, a Phillips catalyst, a metallocene catalyst, or the like. -Α-olefin copolymer is exemplified.

Further, in the medium / high density polyethylene (j), the MFR is preferably in the range of 6 to 100 g / 10 minutes, more preferably 8 to 60 g / 10 because the ethylene resin composition (l) is excellent in laminating workability. It is a range of minutes.

Further, the density of the medium / high density polyethylene (j) is more preferably ^{945 to 975 kg / m 3} because the ethylene resin composition (l) is excellent in laminating workability and productivity.

The MFR of the high-pressure method low-density polyethylene (k) is more preferably in the range of 0.3 to 10 g / 10 minutes, most preferably 1 to 4 g / min, because the ethylene-based resin composition (l) is excellent in extrusion laminating processability. It is in the range of 10 minutes.

Further, in the high-pressure method low-density polyethylene (k), the density is preferably in the range of ^{910 to 935 kg / m 3 because the ethylene-based resin composition (l) is excellent in film-forming stability.}

Further, the SR of the high-pressure method low-density polyethylene (k) is more preferably in the range of 1.75 to 2.20, and most preferably 1. It is in the range of 90 to 2.20.

The MFR of the ethylene resin composition (l) is preferably in the range of 1 to 50 g / 10 minutes, more preferably in the range of 3 to 20 g / 10 minutes, because it is excellent in laminate moldability.

Further, the polyethylene-based resin (h) constituting the present invention may be blended with other polyolefins such as polypropylene, and the blending ratio of these polyolefins is 1 to 30% by weight, which is the laminate moldability and the appearance of the laminate. It is preferable from the point of view.

When the polyolefin is mixed with the polyethylene-based resin (h) constituting the laminate of the present invention, it may be a pellet mixture in which the pellets of the polyethylene-based resin (h) and the pellets of the polyolefin are mixed in a solid state. A mixture melt-kneaded with a shaft extruder, a twin-screw extruder, a kneader, a polyolefin, or the like is preferable because a product with stable quality can be obtained. When a melt-kneading device is used, the melting temperature is preferably about 300 ° C., which is the melting point of the polyethylene resin.

Further, the polyethylene-based resin (h) constituting the present invention contains, if necessary, additives generally used for polyolefin resins, such as antioxidants, light stabilizers, antistatic agents, lubricants, and blocking inhibitors. May be added as long as the object of the present invention is not impaired.

By heating such a foaming laminate, a foamed laminate in which the layer (A) is foamed can be obtained.

As a heating method in the method for obtaining the laminate of the present invention by heating foaming, in addition to hot air, electric heat, and electron beam, the laminate is formed into a container shape, and a high-temperature object is filled therein to utilize the heat of the filling material. Any means can be used. The heating can be performed by a method of performing batch-type in an oven, a method of continuously performing by a conveyor or the like, or the like.

The heat source for heating is not particularly limited as long as this object is achieved, and hot air, electric heat, electron beam, etc. can be exemplified for the laminated body and the molded container, and a high temperature object is internally filled in the laminated body and the molded container. Then, the heat of the filling material can be used as an example. Further, the heating method can be performed by a method of performing batch-type in an oven, a method of continuously performing by a conveyor or the like, or the like.

Conditions such as heating temperature and heating time are not particularly limited as long as the object of the present invention is achieved. Generally, when hot air is used as a heat source, the heating temperature is 110 ° C. or higher and 150 ° C. or lower, and the air volume is 0. .5 to 2.0 m ³ / hour, heating time is 10 seconds to 6 minutes. Further, when the polyethylene-based resin composition (c) is used, the heating temperature is preferably 110 ° C. or higher and lower than the melting point of the crystalline thermoplastic resin (b).

The thickness of the layer (A) constituting the laminate of the present invention is preferably 800 μm or more, more preferably 900 μm or more, and most preferably 1000 μm or more because of its excellent heat insulating properties.

The foamed laminate of the present invention is used at least as a heat insulating paper container used for a body member.

The polyethylene-based resin for extrusion laminating of the present invention can obtain a foaming laminate and a foamed laminate that are highly productive and exhibit excellent heat insulating properties and foamed appearance.

The relationship between MFR and SR of the polyethylene-based resin described in the examples is shown.

Hereinafter, the present invention will be described with reference to Examples and Comparative Examples, but the present invention is not limited thereto.
(1) Density Density was measured according to JIS K6922-1 (1997).
(2) Melt mass flow rate of polyethylene resin (MFR _PE )
MFRPE was measured according to JIS K6922-1 (1997).
(3) Melting point of crystalline thermoplastic resin (Tm _CP )
Tm _CP was measured according to JIS K7122 (1987).
(4) Glass transition temperature (Tg) of amorphous thermoplastic resin
Tg was measured according to JIS K7122 (1987).
(5) Melt mass flow rate (MFR) of polyethylene resin
MFR was measured according to JIS K6922-1 (1997).
(6) Swell ratio (SR)
Using the melt indexer used in JIS K6922-1 (1997), extrude the resin filled in the device from the orifice under the conditions of a temperature of 235 ° C and an extrusion rate of 3 g / min, and insert isopropanol installed directly under the orifice. A strand-shaped extruded product was collected from a measuring cylinder and determined by dividing _{the strand diameter (D) by the orifice diameter (D 0) of the melt indexer.}
(7) Melt tension at 130 ° C. (MS ₁₃₀ )
A capillary viscometer with a barrel diameter of 9.55 mm equipped with a die and a heat retaining chamber having a length of 8 mm, a diameter of 2.095 mm, and an inflow angle of 90 ° in a thermostatic chamber set at 23 ° C. (Toyo Seiki Seisakusho, trade name: Capillograph) is filled with 18 g of polyethylene resin, the piston descent speed is set to 10 mm / min, the take-up speed is set to 2.0 m / min, and the load (mN) required for take-back is melt tension. It was measured as (MS _130).
(8) Melt tension at 190 ° C (MS ₁₉₀ )
A capillary viscometer with a barrel diameter of 9.55 mm equipped with a die and a heat insulating chamber with a length of 8 mm, a diameter of 2.095 mm, and an inflow angle of 90 ° in a thermostatic chamber set at 23 ° C. (Toyo Seiki Seisakusho, trade name: Capillograph) is filled with 18 g of polyethylene resin, the piston descent speed is set to 10 mm / min, the take-up speed is set to 10 m / min, and the load (mN) required for take-back is set to the melt tension (MS). _It was measured as 190).
(9) Heat Foaming A gear aging tester (No. 102-SHF-77 manufactured by Yasuda Seiki Seisakusho Co., Ltd.), in which a sample obtained by cutting the laminate obtained in the Example into a size of 10 cm × 20 cm and forming a cylindrical shape, was heated to a predetermined temperature. After allowing it to stand for a predetermined time while applying hot air inside, it was taken out and cooled to room temperature in the air.
(10) Moisture content of paper base material The paper base material before laminating the polyethylene resin was measured using a Karl Fischer method moisture measuring device (manufactured by Mitsubishi Chemical Corporation, trade name CA-05). The measurement temperature is 165 ° C.
(11) Foam layer thickness A sample of the foam obtained in the example and the laminated laminate before foaming as a blank was taken, and a cross-sectional photograph was taken with an optical microscope. The thickness of the foam layer was measured from the cross-sectional photograph and measured at 5 points.
(12) State of foamed surface The smoothness of the surface of the obtained foam was visually observed. The case where the surface smoothness was good was evaluated as ⊚, the case where the surface smoothness was slightly good was evaluated as ◯, the case where the surface was good but slightly inferior was evaluated as Δ, and the case where the surface was poor was evaluated as ×.

Example 1
As the resin of the layer (A), MFR is 14 g / 10 minutes, density is 917 kg / m ³ , SR is 1.64, high pressure method low density polyethylene (manufactured by Toso Co., Ltd., A1) 99.9% by weight, Tm. _A propylene homopolymer having a CP of 163 ° C (manufactured by Nippon Polypro Co., Ltd., trade name Novatec PP MA1B, B1) is blended to 0.1% by weight, and a single shaft extruder (manufactured by Placo Co., Ltd., diameter 50 mm) is blended. Polyethylene resin (D1, MFR 14 g / 10 min, density 917 kg / m3, SR 1.64, MS ₁₃₀ 72 mN, MS _{190 19} mN) melt-kneaded in High-density polyethylene (trade name Petrosen LW04-1 manufactured by Toso Co., Ltd.) (E1) having a density of 940 kg / m ^{3 was used.}

First, the (D1) is supplied to a single screw extruder laminator having a screw diameter 90 mm (manufactured by Musashinokikai Ltd.), extruded from a T-die at a temperature of 320 ° C., the water content is 25.6 g / ^{m 2,} a basis Extrusion laminating was performed on a paper substrate having an amount of 320 g / m ² so that the take-up speed was 80 m / min, the air gap length was 130 mm, and the thickness was 70 μm. Further, (E1) is supplied to a single-screw extruder (manufactured by Musashinokikai Co., Ltd.) having a screw having a diameter of 90 mmφ, and at a temperature of 320 ° C., a take-up speed of 80 m / min, and an air gap length of 130 mm, (E1). Was extruded to a thickness of 40 μm to obtain a laminate in which the polyethylene-based resin composition (D1), the paper substrate, and the high-density polyethylene (E1) were laminated in this order. The obtained laminate was heated at 120 ° C. for 5 minutes and foamed to obtain a foamed laminate. With respect to the obtained foamed laminate, the thickness of the foamed layer and the state of the foamed surface were evaluated. The evaluation results are shown in Table 1.

Example 2
As the resin of the layer (A), 99.5% by weight of high-pressure low-density polyethylene (A1) and 0.5% by weight of the propylene homopolymer (B1) were blended in a single-screw extruder (Placo Co., Ltd.). Example 1 except that a polyethylene resin (D2, MFR 14 g / 10 minutes, density 917 kg / m ³ , SR 1.64, MS ₁₃₀ 78 mN, MS _{190 19 mN) melt-kneaded in (diameter 50 mm) was used.} A foamed laminate was obtained by the same method as in the above. The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 1.

Example 3
As the resin of the layer (A), 99.0% by weight of high-pressure low-density polyethylene (A1) and 1.0% by weight of the propylene homopolymer (B1) were blended in a single-screw extruder (Placo Co., Ltd.). Example 1 except that a polyethylene resin (D3, MFR 14 g / 10 minutes, density 917 kg / m ³ , SR 1.64, MS ₁₃₀ 102 mN, MS _{190 19 mN) melt-kneaded with a diameter of 50 mm) was used.} A foamed laminate was obtained by the same method as in the above. The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 1.

Example 4
As the resin of the layer (A), 96.0% by weight of high-pressure low-density polyethylene (A1) and 4.0% by weight of the propylene homopolymer (B1) were blended in a single-screw extruder (Placo Co., Ltd.). Example 1 except that a polyethylene resin (D4, MFR 14 g / 10 minutes, density 917 kg / m ³ , SR 1.64, MS ₁₃₀ 135 mN, MS _{190 19 mN) melt-kneaded in (diameter 50 mm) was used.} A foamed laminate was obtained by the same method as in the above. The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 1.

Example 5
As the resin of the layer (A), a propylene / ethylene copolymer having 99.0% by weight of high-pressure low-density polyethylene (A1) and a Tm _CP of 145 ° C. (manufactured by Japan Polypropylene Corporation, trade name Novatec PP FL02A, B2) ) To 1.0% by weight, and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). Polyethylene resin (D5, MFR 14 g / 10 minutes, density 917 kg / m ³ , SR A foamed laminate was obtained by the same method as in Example 1 except that 1.64, MS ₁₃₀ 94 mN, MS _{190 19 mN) was used.} The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 1.

Example 6
As the resin of the layer (A), 99.0% by weight of high-pressure low-density polyethylene (manufactured by Tosoh Corporation, A2) having an MFR of 14 g / 10 minutes, a density of 918 kg / m ^{3 and an SR of 1.68,} A polyethylene resin (D6, MFR 14 g / 10 minutes, density) in which a propylene homopolymer (B1) was blended so as to be 1.0% by weight and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). A foamed laminate was obtained by the same method as in Example 1 except that 918 kg / m ³ , SR 1.68, MS ₁₃₀ 115 mN, and MS _{190 28 mN) were used.} The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 1.

Example 7
As the resin of the layer (A), 99.0% by weight of high-pressure low-density polyethylene (manufactured by Tosoh Corporation, A3) having an MFR of 24 g / 10 minutes, a density of 918 kg / m ^{3, and an SR of 1.45.} A polyethylene resin (D7, MFR 24 g / 10 minutes, density) in which a propylene homopolymer (B1) was blended so as to be 1.0% by weight and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). A foamed laminate was obtained by the same method as in Example 1 except that 918 kg / m ³ , SR 1.45, MS ₁₃₀ 125 mN, and MS _{190 9.0 mN) were used.} The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 1.

Example 8
As the resin of the layer (A), 99.0% by weight of high-pressure low-density polyethylene (manufactured by Tosoh Corporation, A4) having an MFR of 45 g / 10 minutes, a density of 924 kg / m ^{3, and an SR of 1.31 is used.} A polyethylene resin (D8, MFR 45 g / 10 minutes, density) in which a propylene homopolymer (B1) was blended so as to be 1.0% by weight and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). A foamed laminate was obtained by the same method as in Example 1 except that 924 kg / m ³ , SR 1.31, MS ₁₃₀ 85 mN, and MS _{190 4.0 mN) were used.} The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 1.

Example 9
As the resin of the layer (A), high-pressure low-density polyethylene (manufactured by Tosoh Corporation, A4) is blended in an amount of 92.0% by weight, and a propylene homopolymer (B1) is blended in an amount of 8.0% by weight. Polyethylene resin (D9, MFR 45 g / 10 minutes, density 924 kg / m ³ , SR 1.31, MS ₁₃₀ 126 mN, MS ₁₉₀ 4.0 mN) melt-kneaded by an extruder (Placo Co., Ltd., diameter 50 mm) A foamed laminate was obtained by the same method as in Example 1 except that it was used. The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 1.

実施例記載のポリエチレン系樹脂のＭＦＲとＳＲの関係を図１に示す。この図の通り、明細書記載の式（１）を満たす実施例７は、式（１）を満たさない実施例８よりも発泡外観に優れる。更に、式（２）を満たす実施例６はより発泡外観が優れ、式（３）を満たす実施例３は、より発泡層厚みに優れる。

The relationship between MFR and SR of the polyethylene-based resin described in the examples is shown in FIG. As shown in this figure, Example 7 satisfying the formula (1) described in the specification is superior in foaming appearance to Example 8 not satisfying the formula (1). Further, Example 6 satisfying the formula (2) has a more excellent foam appearance, and Example 3 satisfying the formula (3) has a more excellent foam layer thickness.

Regarding the slopes of equations (1) to (3), the high-pressure method has ^{a density equal to 918 kg / m 3} , an MFR of 24 g / 10 minutes, a density of 918 kg / m ^{3, and an SR of 1.45.} Low-density polyethylene, MFR 13 g / 10 minutes, density 918 kg / m ³ , SR 1.71 High-density method Low-density polyethylene and MFR 8 g / 10 minutes, density 918 kg / m ³ , SR 2.05 It was calculated from the correlation between MFR and SR of high-density low-density polyethylene (both manufactured by Toso Co., Ltd.).

Example 10
As the resin of the layer (A), polyethylene terephthalate (trade name: Unitica PET resin MA-2103, B3 manufactured by _{Unitica) having a Tm CP} of 255 ° C. and 99.9% by weight of high-pressure low-density polyethylene (A3) was 0.1. ^{Polyethylene resin (D10, MFR 24 g / 10 minutes, density 918 kg / m 3} , SR 1.65, MS) that was blended to a weight% and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). _A foamed laminate was obtained by the same method as in Example 1 except that 130 85 mN and MS _{190 29 mN) were used.} The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 2.

Example 11
As the resin of the layer (A), poly (4-methyl1-pentene) having 99.9% by weight of high-pressure low-density polyethylene (A3) and a Tm _CP of 224 ° C. (trade name TPX MX002, B4 manufactured by Mitsui Chemicals). Is blended to 0.1% by weight and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). Polyethylene resin (D11, MFR 24 g / 10 minutes, density 918 kg / m ³ , SR 1 A foamed laminate was obtained by the same method as in Example 1 except that .45, MS ₁₃₀ 80 mN, and MS _{190 27 mN) were used.} The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 2.

Example 12
As the resin of the layer (A), ethylene / vinyl alcohol copolymer (trade name EVAL E105B, B5 manufactured by Kuraray _{) having a Tm CP} of 165 ° C. and 99.9% by weight of high-pressure low-density polyethylene (A3) was used as the resin. ^{Polyethylene resin (D12, MFR 24 g / 10 minutes, density 918 kg / m 3} , SR 1.45, which was blended to 1% by weight and melt-kneaded with a single-screw extruder (Kuraray Co., Ltd., diameter 50 mm). A foamed laminate was obtained by the same method as in Example 1 except that _{MS 130} 75 mN and MS _{190 19 mN) were used.} The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 2.

Example 13
As the resin of the layer (A), 0.1% by weight of high-pressure low-density polyethylene (A3) and 0.1 of polybutylene terephthalate (trade name Novaduran 5010R5, B6 manufactured by Mitsubishi Engineering Plastics _{) having a Tm CP of 224 ° C.} ^{Polyethylene resin (D13, MFR 24 g / 10 minutes, density 918 kg / m 3} , SR 1.45, MS) that was blended to a weight% and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). _A foamed laminate was obtained by the same method as in Example 1 except that 130 82 mN and MS _{190 28 mN) were used.} The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 2.

Example 14
As the resin of the layer (A), 99.9% by weight of high-pressure low-density polyethylene (A3) and 0.1% by weight of polyamide 6 (trade name UBE nylon 1022B, B7 manufactured by Ube Industries, Ltd.) having a TmCP of 220 ° C. Polyethylene resin (D14, MFR 24g / 10 minutes, density 918kg / m ³ , SR 1.45, MS ₁₃₀ 80mN, A foamed laminate was obtained by the same method as in Example 1 except that _{MS 190 26 mN) was used.} The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 2.

実施例１５
（Ａ）層の樹脂として、高圧法低密度ポリエチレン（Ａ１）を９９．０重量％、Ｔｇが１５８℃であるシクロオレフィンコポリマー（Ｔｏｐａｓ Ａｄｖａｎｃｅｄ Ｐｏｌｙｍｅｒ Ｉｎｃ．製 商品名ＴＯＰＡＳ ６０１５Ｓ−０４、Ｃ１）を１．０重量％になるよう配合し、単軸押出機（プラコー（株）製 口径５０ｍｍ）にて溶融混練したポリエチレン系樹脂（Ｄ１５、ＭＦＲ １４ｇ／１０分、密度 ９１７ｋｇ／ｍ^３、ＳＲ １．６４、ＭＳ_１３０ １０５ｍＮ、ＭＳ_１９０ １９ｍＮ）を使用した以外は、実施例１と同様の手法により発泡積層体を得た。得られた発泡積層体について、発泡層厚み及び発泡外観を評価した。評価の結果を表３に示す。

Example 15
As the resin of the layer (A), 1 is a cycloolefin copolymer (trade name TOPAS 6015S-04, C1 manufactured by Topas Advanced Polymer Inc.) containing 99.0% by weight of high-pressure low-density polyethylene (A1) and a Tg of 158 ° C. ^{Polyethylene resin (D15, MFR 14 g / 10 minutes, density 917 kg / m 3} , SR 1.64) blended to 0.0% by weight and melt-kneaded with a single-screw extruder (Placo Co., Ltd. caliber 50 mm). , MS ₁₃₀ 105 mN, MS _{190 19} mN), and a foamed laminate was obtained by the same method as in Example 1. The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 3.

Example 16
As the resin of the layer (A), 1 is a cycloolefin copolymer (trade name TOPAS 6013F-04, C2 manufactured by Topas Advanced Polymer Inc.) containing 99.0% by weight of high-pressure low-density polyethylene (A1) and a Tg of 138 ° C. ^{Polyethylene resin (D16, MFR 14 g / 10 minutes, density 917 kg / m 3} , SR 1.64) blended to 0.0% by weight and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). , MS ₁₃₀ 95 mN, MS _{190 19} mN), and a foamed laminate was obtained by the same method as in Example 1. The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 3.

Example 17
As the resin of the layer (A), 1.0% by weight of high-pressure low-density polyethylene (A1) and 1.0 of cycloolefin polymer (trade name Zeonex F52R, C3 manufactured by Nippon Zeon Co., Ltd.) having a Tg of 156 ° C. ^{Polyethylene resin (D17, MFR 14 g / 10 minutes, density 918 kg / m 3} , SR 1.64, MS) blended to a weight% and melt-kneaded with a single-screw extruder (Placo Co., Ltd. diameter 50 mm). _A foamed laminate was obtained by the same method as in Example 1 except that 130 100 mN and MS _{190 19 mN) were used.} The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 3.

Example 18
As the resin of the layer (A), 1 9.0% by weight of high-pressure low-density polyethylene (A1) and 1 polycarbonate (trade name: Panlite L-1255Y, C4 manufactured by Teijin Limited) having a Tg of 150 ° C. ^{Polyethylene resin (D18, MFR 14 g / 10 minutes, density 917 kg / m 3} , SR 1.64) blended to 0.0% by weight and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). , MS ₁₃₀ 110 mN, MS _{190 19} mN), and a foamed laminate was obtained by the same method as in Example 1. The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 3.

比較例１
（Ａ）層の樹脂として高圧法低密度ポリエチレン（Ａ１）を使用した以外は、実施例１と同様の手法により発泡積層体を得た。得られた発泡積層体について、発泡層厚み及び発泡外観を評価した。評価の結果を表４に示す。発泡外観に劣っていた。

Comparative Example 1
A foamed laminate was obtained by the same method as in Example 1 except that the high-pressure low-density polyethylene (A1) was used as the resin for the layer (A). The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 4. It was inferior in foam appearance.

Comparative Example 2
A foamed laminate was obtained by the same method as in Example 1 except that the high-pressure low-density polyethylene (A2) was used as the resin for the layer (A). The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 4. It was inferior in foam appearance.

Comparative Example 3
A foamed laminate was obtained by the same method as in Example 1 except that the high-pressure low-density polyethylene (A3) was used as the resin for the layer (A). The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 4. It was inferior in foam appearance.

Comparative Example 4
A foamed laminate was obtained by the same method as in Example 1 except that high-pressure low-density polyethylene (A4) was used as the resin for the layer (A). The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 4. It was inferior in foam appearance.

Comparative Example 5
As the resin of the layer (A), 99.0% by weight of high-pressure low-density polyethylene (manufactured by Tosoh Corporation, A5) having an MFR of 7 g / 10 minutes, a density of 922 kg / m ^{3, and an SR of 1.94, propylene.} Polyethylene resin (D19, MFR 7 g / 10 minutes, density 922 kg) in which the homopolymer (B1) was blended so as to be 1.0% by weight and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). A foamed laminate was obtained by the same method as in Example 1 except that / m ³ , SR 1.94, MS ₁₃₀ 151 mN, MS _{190 49 mN) was used.} The foamed layer thickness and the foamed appearance of the obtained foamed laminate were evaluated. The evaluation results are shown in Table 4. It was inferior in foam appearance.

Comparative Example 6
As the resin of the layer (A), 99.0% by weight of high-pressure low-density polyethylene (manufactured by Tosoh Corporation, A6) having an MFR of 58 g / 10 minutes, a density of 917 kg / m ^{3, and an SR of 1.26 was used.} A polyethylene resin (D20, MFR 58 g / 10 minutes, density) in which a propylene homopolymer (B1) was blended so as to be 1.0% by weight and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). A laminate before foaming was obtained by the same method as in Example 1 except that 917 kg / m ³ , SR 1.26, MS ₁₃₀ 75 mN, and MS _{190 1.5 mN) were used.} The evaluation results are shown in Table 4. When the layer (A) was formed, the thickness of the laminate was not stable, and the foamed laminate could not be evaluated.

The foaming laminate of the present invention is suitably used for containers that require heat insulation, such as paper containers for high-temperature beverages such as coffee and soup, and containers for instant foods such as instant noodles.

Claims (10)

A foam laminate comprising at least a layer (A) composed of a polyethylene resin composition (d) for extrusion lamination satisfying the following (i) to (iii) and a paper base material layer adjacent thereto.
(I) Melt mass flow rate (MFR) measured by JIS K6922-1 (1997) is 8 g / 10 minutes or more and 50 g / 10 minutes or less. (Ii) Melt tension measured at a temperature of 130 ° C. and a take-up speed of 2 m / min. MS ₁₃₀ ) is 70 mN or more and 150 mN or less (iii) The melt tension (MS ₁₉₀ ) measured at a temperature of 190 ° C. and a take-up speed of 10 m / min is 3 mN or more and 30 mN or less. Extrusion laminating polyethylene resin composition (d), the ratio _MS 130 _{/ MS 190} of _{MS 130} for _{MS 190} of 4.0 or more, foam of claim 1, wherein the at 30.0 or less Laminated body . The foaming use according to claim 1 or 2, wherein the polyethylene-based resin composition (d) for extrusion lamination has a swell ratio (SR) measured at 235 ° C. of 1.40 or more and less than 1.70. Laminated body . The foaming laminate according to any one of claims 1 to 3, wherein the MFR and SR of the polyethylene resin composition (d) for extrusion lamination satisfy the following formula (1).
SR <-1.25 x log (MFR) +3.21 (1) Except for the high-pressure method low-density polyethylene (a) 95 to 99.9 parts by weight, and at least the high-pressure method low-density polyethylene (a), wherein the polyethylene-based resin composition (d) for extrusion lamination satisfies the following (iv) to (v). The polyethylene-based resin composition (d) containing 0.1 to 5 parts by weight of either the crystalline thermoplastic resin (b) satisfying the following (vi) or the amorphous thermoplastic resin (c) satisfying (vi). The foaming laminate according to any one of claims 1 to 4, wherein the total amount of (a), (b) and (c) is 100 parts by weight).
(Iv) Melt mass flow rate (MFR) measured by JIS K6922-1 (1997) is 8 g / 10 minutes or more and 50 g / 10 minutes or less (v) Density measured by JIS K6922-1 (1997) is 910 kg / It is m ³ or more and 930 kg / m ³ or less.
(Vi) JIS K7121 (2012 year) melting temperature measured by the 125 ° C. or higher, 300 ° C. or less (v ii) JIS K7121 (2012 year) glass transition temperature measured by the 125 ° C. or higher, 300 ° C. or less The crystalline thermoplastic resin (b) is any one of a polypropylene resin, a poly (4-methyl-1-pentene), an ethylene / vinyl alcohol copolymer, a polyester resin, and a polyamide resin. The foaming laminate according to claim 5. The foaming laminate according to claim 5, wherein the amorphous thermoplastic resin (c) is either a cycloolefin polymer, a cycloolefin copolymer, or polycarbonate. The foaming laminate according to any one of claims 5 to 6, wherein the swell (SR) of the low-density polyethylene (a) measured at 235 ° C. is 1.30 or more and 1.85 or less. A foamed laminate according to any one of claims 1 to 8, wherein the layer (A) of the foamed laminate is foamed. A heat insulating paper container characterized in that at least the body member is the foamed laminate according to claim 9.

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