JP6800406B2 - Foam laminate and foam laminate - Google Patents

Description

The present invention relates to an effervescent laminate and an effervescent laminate that exhibit good heat insulating properties and foamed appearance, and are excellent in box-making suitability.

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, as a means for obtaining a foam having a thick foam layer, a method of vacuum-sucking at least a part of the foam surface to thicken the foam layer of the foam cell has been proposed (see, for example, Patent Document 4). 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 a 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 thermoplastic synthetic resin film having a low melting point is heat-treated and foamed has been proposed (see, for example, Patent Document 5).

However, the method of thickening the foam layer by vacuum suction is inferior in cost performance because a vacuum suction device is required and a step of applying vacuum suction is required in the manufacturing process, and further, the surface smoothness of the foam layer is smooth. The foam appearance was poor. Further, the heat insulating paper container having a high melting point thermoplastic synthetic resin on the inner wall surface was inferior in hot tack property and poor box-making suitability.

Further, as a means for obtaining a foam having excellent box-making suitability, a method of providing a sealant layer containing an ethylene / α-olefin copolymer on the inner wall surface of the refractory thermoplastic resin has been proposed (for example, Patent Documents). 6).

However, the method of providing the high melting point resin layer and the sealant layer has a complicated layer structure and is inferior in cost performance.

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 JP-A-2007-217024 Japanese Unexamined Patent Publication No. 2014-124996

An object of the present invention is to provide an effervescent laminate and an effervescent laminate that exhibit good heat insulating properties and foamed appearance, and are excellent in box-making suitability.

As a result of diligent studies to solve the above problems, the present inventors have found that a specific foaming laminate exhibits good heat insulating properties and foaming appearance, and is excellent in box-making suitability, and completes the present invention. I came to do it.

That is, the low-density polyethylene (a) including at least the (A) layer / paper base material layer / (B) layer, and the (A) layer satisfying (i) to (ii), and the (B) layer are (iii) to (iii). The present invention relates to a foaming laminate characterized by being composed of a polyethylene-based resin (b) satisfying (iv).

(I) Melt mass flow rate (MFR) measured by JIS K6922-1 (1997) is 5 g / 10 minutes or more and 30 g / 10 minutes or less (ii) Density measured by JIS K6922-1 (1997) is 910 kg / m. ³ above 930 kg / ^{m 3} or less (iii) JIS K6922-1 (1997 years) density measured by the 930 kg / ^{m 3} or more 970 kg / ^{m 3} or less (iv) a copolymer of ethylene and having 6 or more α- olefins carbon (Hereinafter referred to as ethylene / α-olefin copolymer (c)) is contained in an amount of 5% by weight or more and 70% by weight or less. Further, the foaming is characterized in that the layer (A) of the foaming laminate is foamed. It relates to a laminate.

Hereinafter, the present invention will be described in detail.

The low-density polyethylene (a) constituting the laminate of the present invention is composed of high-pressure low-density polyethylene (g), linear low-density polyethylene (h), or a composition thereof.

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

The linear low-density polyethylene (h) can be obtained by copolymerizing ethylene and α-olefin by a high-, medium- and low-pressure ion polymerization method using a Ziegler-Natta catalyst, a Phillips catalyst, and a metallocene catalyst.

Examples of the α-olefin used for the linear low-density polyethylene (h) include propylene, 1-butene, 4-methyl-1-pentene, 3-methyl-1-butene, 1-pentene, 1-hexene and 1-hexene. , 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene and the like, and one or more of these may be used.

The density (hereinafter simply abbreviated as density) measured by JIS K6922-1 (1997) of low-density polyethylene (a) is in the range of 910 to 930 kg / m ³ because of its excellent heat insulating properties and foamed appearance. It is more preferably in the range of 914 to 925 kg / m ³ , and even more preferably in the range of 916 to 923 kg / m ³ . If the density of the low-density polyethylene (a) is less than 910 kg / m ^3, it is not preferable because the foamed appearance is inferior, and if it exceeds 930 kg / m ³ , it is not preferable because the heat insulating property is inferior.

The melt mass flow rate (hereinafter, simply abbreviated as MFR) measured by JIS K6922-1 (1997) of low-density polyethylene (a) is in the range of 5 to 30 g / 10 minutes, and has excellent heat insulating properties and foamed appearance. From its superiority, the range is preferably 12 to 24 g / 10 minutes, more preferably 12 to 18 g / 10 minutes, and most preferably 12 to 16 g / 10 minutes. When the MFR of the low-density polyethylene (a) is less than 5 g / 10 minutes, it is not preferable because the foamed appearance is inferior, and when it exceeds 30 g / 10 minutes, the laminating workability is inferior, which is not preferable.

Of these, the low-density polyethylene (a) constituting the present invention has a swell ratio (hereinafter simply abbreviated as SR) measured at 235 ° C. because it has low melt elasticity during box-making and is excellent in box-making suitability. High pressure method low density polyethylene (c) of 40 or more and 1.75 or less is preferable. Further, the SR of the high pressure method low density polyethylene (c) is more preferably in the range of 1.50 to 1.70, and most preferably in the range of 1.55 to 1.65 because it is more excellent in foamed appearance.

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 low-density polyethylene (a) constituting the present invention may be blended with other polyolefins such as an ethylene / α-olefin copolymer, but the layer (A) is made by a high-pressure method because it has an excellent foamed appearance. It is preferably composed of only the density polyethylene (c).

When the polyolefin is mixed with the low-density polyethylene (a) constituting the laminate of the present invention, it may be a pellet mixture in which the pellets of the low-density polyethylene (a) 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 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 about 300 ° C., which is the melting point of the polyolefin resin.

Further, the low-density polyethylene (a) constituting the laminate of the present invention is generally used as a polyolefin resin such as an antioxidant, a light stabilizer, an antistatic agent, a lubricant, and an antiblocking agent, if necessary. The additive may be added as long as the object of the present invention is not impaired.

Density of the polyethylene resin (b) constituting the laminate of the present invention, thermal insulation, due to excellent stability of the foam is in the range of 930~970kg / ^{m 3,} more preferably 935~970kg / ^{m 3} The range is, most preferably the range of 945 to 965 kg / m ³ . If the density of the polyethylene resin (b) is less than 930 kg / m ^3, it is not preferable because it is inferior in heat insulating properties, and if it is more than 970 kg / m ³ , it is not preferable because it is inferior in foamed appearance.

The polyethylene-based resin (b) constituting the laminate of the present invention is an ethylene homopolymer, an ethylene / α-olefin copolymer or a composition thereof, and the ethylene / α-olefin copolymer (c) is 5 It contains 70% by weight or more and 70% by weight or less. The form of the molecular chain of the polyethylene-based resin may be linear or may have branches. Such a polyethylene-based resin (b) is not particularly limited, and may not be out of the density range.

Examples of the ethylene homopolymer include medium- and low-pressure ethylene homopolymers and high-pressure low-density polyethylene. Medium / Low Pressure Method Ethylene homopolymers can be obtained by conventionally known medium / low pressure ion polymerization methods. 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 high / medium / low pressure ion polymerization methods using a Ziegler-Natta catalyst, a Philips catalyst, a metallocene catalyst and the like can be exemplified. Such a copolymer can be conveniently selected from commercially available products.

Since the polyethylene-based resin (b) constituting the present invention is excellent in box-making suitability, it contains 5 to 70% by weight of an ethylene / α-olefin copolymer (c) composed of an α-olefin having at least 6 carbon atoms. It is preferably 7 to 50% by weight, more preferably 7% by weight or more and 30% by weight or less, because it contains, and is excellent in foamability and box-making suitability. If the blending amount of the ethylene / α-olefin copolymer (c) is less than 5% by weight, it is not preferable because it is inferior in box-making suitability, and if it exceeds 70% by weight, it is not preferable because it is inferior in heat insulating property.

Examples of the α-olefin used in such an ethylene / α-olefin copolymer include 1-hexene, 1-hexene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene and the like. However, it is preferable to use 1-hexene and 1-octene because they are excellent in foamed appearance.

The MFR of the ethylene / α-olefin copolymer (c) is not particularly limited as long as this object is achieved, and is excellent in box-making suitability. Therefore, the range of 1 to 40 g / 10 minutes is preferable. It is preferably in the range of 4 to 20 g / 10 minutes.

The density of the ethylene / α-olefin copolymer (c) is not particularly limited as long as this object is achieved, and is excellent in box-making suitability. Therefore, the density is preferably in the range of 870 to 925 kg / m ³ , more preferably. The range is 890 to 920 kg / m ³ .

Further, the molecular weight distribution obtained by gel permeation chromatography (hereinafter, GPC) of the ethylene / α-olefin copolymer (c) is 1.3 to 3.0 or less because it is excellent in box-making suitability. The range is preferred. The molecular weight distribution can be calculated by the ratio Mw / Mn of the weight average molecular weight (Mw) and the number average molecular weight (Mn), which are standard polyethylene equivalent values measured by GPC.

Among these, since the box-making suitability, foamability, and laminate moldability are excellent, at least the ethylene / α-olefin copolymer (c) is 5 to 70 parts by weight and the density is 940 to 980 kg / m ³ or less. Polyethylene resin composition (f) ((c)) consisting of 20 to 80 parts by weight of high-density polyethylene (d) and 10 to 50 parts by weight of high-density low-density polyethylene (e) having an MFR of 1 to 10 g / 10 minutes or less. , (D) and (e) are preferably 100 parts by weight).

The high-density polyethylene (d) can be obtained by an ethylene copolymer obtained by a conventionally known medium-low pressure ion polymerization method, a high-medium-low pressure ion polymerization method using a Ziegler-Natta catalyst, a Phillips catalyst, a metallocene catalyst, or the like. Ethylene / α-olefin copolymers are exemplified.

Further, in the high-density polyethylene (d), since the ethylene-based resin composition (f) is excellent in laminating workability, the MFR is preferably in the range of 6 to 100 g / 10 minutes, more preferably 8 to 60 g / 10 minutes. The range.

Further, the density of the high-density polyethylene (d) is more preferably 945 to 975 kg / m ³ because the ethylene-based resin composition (f) is excellent in laminating workability and productivity.

The MFR of the high-pressure method low-density polyethylene (e) is more preferably in the range of 1 to 8 g / 10 minutes, and most preferably 1 to 4 g / 10 minutes because the ethylene resin composition (f) is excellent in extrusion laminating processability. Is the range of.

Further, in the high pressure method low density polyethylene (e), the density is preferably in the range of 910 to 935 kg / m ³ because the ethylene resin composition (f) is excellent in film formation stability.

Further, the SR of the high-pressure low-density polyethylene (e) is preferably in the range of 1.50 to 3.00, more preferably 1.75, because the film-forming stability of the ethylene-based resin composition (f) is excellent. It is in the range of ~ 2.80, most preferably in the range of 1.90 to 2.20.

The MFR of the ethylene resin composition (f) 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 (b) 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 in terms of laminate moldability and appearance of the laminate. It is preferable from the point of view.

When the polyolefin is mixed with the polyethylene resin (b) constituting the laminate of the present invention, it may be a pellet mixture in which the pellets of the polyethylene resin (b) 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 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 about 300 ° C., which is the melting point of the polyethylene resin.

Further, the polyethylene-based resin (b) constituting the present invention includes, 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.

The thickness of the layer (A) before foaming, which constitutes the foamed laminate of the present invention, is not particularly limited as long as the object of the present invention is achieved, but is in the range of 40 to 150 μm because of its excellent foaming appearance. It is preferably, more preferably 50 to 120 μm, and even more preferably 60 to 100 μm.

The thickness of the layer (B) is not particularly limited as long as the object of the present invention is achieved, but it is preferably 20 to 100 μm because of its excellent foamability and less problems such as breakage. From the viewpoint of economy, the range of 20 to 50 μm is most suitable.

The thickness of the layer (A) constituting the foamed laminate of the present invention is preferably 600 μm or more, more preferably 800 μm or more, and most preferably 1000 μm or more because of its excellent heat insulating properties.

The paper base material constituting the laminate of the present invention 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 low density polyethylene (a) can be improved. It is preferable, and more preferably, 200 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 low density polyethylene (a) is improved. 30 g / ^{m 2,} and most preferably 20~26g / ^{m 2.}

As a method for obtaining the foamed laminate of the present invention, a method of extrusion-laminating low-density polyethylene (a) and polyethylene-based resin (b) is exemplified, but since the processing is easy, the low-density polyethylene (a) A method of tandem laminating the polyethylene resin (b) with the polyethylene resin (b) is preferable.

As a method for obtaining a foam 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.

Further, in the extrusion laminating process, immediately after the polyethylene resin 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 the base material is bonded to the base material. It is preferable because it has excellent adhesiveness to the 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.

In the extrusion laminating method in the method for obtaining the foamed laminate of the present invention, in order to further improve the adhesiveness between the thermoplastic resin layer and the base material layer, the temperature at which the polyethylene-based 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.

As a method for obtaining the foamed laminate of the present invention, water is applied to one or both sides of the paper substrate before laminating the polyethylene resin on the paper substrate layer in order to improve the heat insulating property and economy of the foamed laminate. 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 such dampening devices, for example, the product name "High Rotor S" from Suzuki Sangyo Co., Ltd., the product name "WEKO Rotor Dampening" from Nikka Co., Ltd., and the product name "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 low-density polyethylene (a) can be increased, and the paper substrate and the low-density polyethylene (a) can be applied. And / or because the adhesive strength with the polyethylene resin (b) does not decrease, 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.

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

As a heating method in the method for obtaining the foamed 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, such as. 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 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, and in general, when hot air is used as a heat source, the heating temperature is 150, which is equal to or higher than the melting point of low-density polyethylene (a). Below ° C, the air volume is 0.5 to 2.0 m ³ / hour, and the heating time is 10 seconds to 6 minutes.

The laminate of the present invention is characterized by containing at least the (A) layer / paper base material / (B) layer, and is composed of only the three components of the (A) layer, the paper base material, and the (B) layer. It may contain other components, for example, layer (C). Specifically, (A) layer / paper base material / (B) layer, (A) layer / paper base material / (B) layer / (A) 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, (A) layer / Paper base material / (B) layer / (C) layer, (B) layer / Paper base material / (A) layer / (C) layer, (C) layer / (B) layer / Paper base material / (A) Layer / (B) layer / (C) layer, (A) layer / paper base material / (B) layer / (C) layer / (B) layer / (A) layer, (B) layer / paper base material / Examples include (A) layer / (C) layer / (A) layer / (B) layer. The symbol / between the layers indicates that they are adjacent layers.

Examples of the layer (C) 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 polyvinylidene 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.

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

The foamed laminate of the present invention becomes a foamed laminate having a high magnification when foamed, so that it has good heat insulating properties, exhibits a good foamed appearance, and is excellent in box-making suitability.

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 (MFR)
MFR was measured according to JIS K6922-1 (1997).
(3) 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 put the isopropanol installed directly under the orifice. A strand-shaped extruded product was collected from a graduated cylinder and determined by dividing the strand diameter (D) by the orifice diameter (D ₀ ) of the melt indexer.
(4) Heat Foaming A gear aging tester (No. 102-SHF-77 manufactured by Yasuda Seiki Seisakusho Co., Ltd.) obtained by cutting a laminate obtained in the Example into a size of 10 cm × 20 cm and molding it into a cylindrical shape and heating it to a predetermined temperature. After allowing to stand for a predetermined time while applying hot air inside, the mixture was taken out and cooled to room temperature in air.
(5) 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.
(6) 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.
(7) 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 good but slightly inferior was evaluated as Δ, and the case where the surface was poor was evaluated as ×.
(8) Hot Tackability Two laminated films cut out to a width of 30 mm using a hot tack tester (manufactured by Tester Sangyo Co., Ltd.) from the laminate film obtained in the example so that the (C) layer surface is in contact with the inside. Immediately after heat-sealing with a seal bar with a width of 10 mm and a length of 300 mm with double-sided heating, air pressure of 0.2 MPa, and a sealing time of 1 second, the load of a weight attached to the end of the laminate (45 g each) is applied to T. Peeling was performed. The measurement was performed at a sealing temperature of 140 ° C., and the peeled distance (mm) of the sealed portion was measured. The shorter the peeling distance, the better the box-making suitability, and the better the peeling distance was 150 mm or less.

Example 1
As the resin of the layer (A), high-pressure low-density polyethylene (trade name Petrosen 202K manufactured by Toso Co., Ltd.) (A1) having an MFR of 24 g / 10 minutes, a density of 918 kg / m ³ , and an SR of 1.45 was used. As the resin of the layer (B), an ethylene / 1-hexene copolymer having an MFR of 2.0 g / 10 minutes, a density of 910 kg / m ³ , and a molecular weight distribution of 1.7 (trade name Niporon manufactured by Toso Co., Ltd.) ZHF210K, C1) is 10 parts by weight, MFR is 20 g / 10 minutes, high density polyethylene with a density of 964 kg / m ³ (trade name Niporon Hard 1000, D1 manufactured by Toso Co., Ltd.) is 45 parts by weight, MFR is 3. High-density low-density polyethylene (trade name Petrosen 205, E1 manufactured by Toso Co., Ltd.) with 0 g / 10 minutes, density of 924 kg / m ³ , and SR of 2.02 is blended to 45 parts by weight and uniaxially extruded. An ethylene resin composition (B1, MFR 6.8 g / 10 minutes, density 941 kg / m ³ ) melt-kneaded by a machine (Placo Co., Ltd., diameter 50 mm) was used.

First, a biaxially stretched polyester film (trade name: Ester film E-5100 manufactured by Toyo Spinning Co., Ltd., thickness 25 μm, hereinafter, PET) obtained by applying a polyurethane adhesive blended in the ratio shown below to the corona-treated surface and drying the solvent. (B1) is supplied to a single-screw extruder (manufactured by Musashino Kikai Co., Ltd.) having a screw with a diameter of 90 mmφ on the adhesive-coated surface of (may be described as), and the temperature is 320 ° C. and the take-up speed is 60 m / min. An air gap length of 130 mm was extruded so that the thickness of (B1) was 40 μm, and a laminated film was obtained in which PET and polyethylene resin (B1) were laminated in this order. The hot tack property was evaluated using this laminated film.

Polyurethane adhesive formulation: Takelac A3210 (15 parts) + Takenate A3072 (5 parts) + Ethyl acetate (140 parts)
Takelac A3210 and Takenate A3072 are both manufactured by Mitsui Chemicals Polyurethane Co., Ltd. Adhesive thickness: 0.2 μm
Further, (A1) is supplied to a single-screw extrusion laminator (manufactured by Musashinokikai Co., Ltd.) having a screw having a diameter of 90 mmφ and extruded from a T die at a temperature of 320 ° C., the water content is 24 g / m ² , and the basis weight is 320 g. Extrusion laminating was performed on a paper substrate at / m ² so that the take-up speed was 60 m / min, the air gap length was 130 mm, and the thickness was 70 μm. Further, (B1) 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 60 m / min, and an air gap length of 130 mm, (B1). A laminate having a thickness of 40 μm, high-pressure low-density polyethylene (A1), a paper substrate, and a polyethylene-based resin (B1) was laminated in this order. The obtained laminate was heated at 120 ° C. for 5 minutes and foamed to obtain a foamed laminate. The thickness of the foamed layer and the foamed appearance of the obtained laminate before and after foaming were evaluated.

The evaluation results are shown in Table 1. The thickness of the foamed layer after foaming, the foamed appearance, and the hot tack property were all good.

Example 2
As the resin of the layer (B), the ethylene / 1-hexene copolymer (C1) is 30 parts by weight, the high-density polyethylene (D1) is 50 parts by weight, and the high-pressure low-density polyethylene (E1) is 20 parts by weight. Except for using an ethylene resin composition (B2, MFR 6.9 g / 10 minutes, density 940 kg / m ³ ) that was blended and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). A laminated film and a foamed laminate were obtained by the same method as in Example 1. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 1. The thickness of the foamed layer after foaming, the foamed appearance, and the hot tack property were all good.

Example 3
As the resin of the layer (B), an ethylene / 1-hexene copolymer having an MFR of 1.0 g / 10 minutes, a density of 920 kg / m ³ , and a molecular weight distribution of 1.6 (trade name Niporon manufactured by Toso Co., Ltd.) Z 04P65B, C2) is 50 parts by weight, high density polyethylene (D1) is 40 parts by weight, MFR is 1.6 g / 10 minutes, density is 918 kg / m ³ , SR is 2.50, high pressure method low density polyethylene ( Ethylene resin composition (B3, MFR 3) made by mixing Toso Co., Ltd. brand name Petrosen 360, E2) to 10 parts by weight and melt-kneading with a single-screw extruder (Placo Co., Ltd. caliber 50 mm). A laminate film and a foamed laminate were obtained by the same method as in Example 1 except that .5 g / 10 minutes and a density of 938 kg / m ³ ) were used. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 1. The thickness of the foamed layer after foaming, the foamed appearance, and the hot tack property were all good.

Example 4
As the resin of the layer (B), an ethylene 1-octene copolymer having an MFR of 3.0 g / 10 minutes, a density of 875 kg / m ³ , and a molecular weight distribution of 2.2 (trade name Affinity KC8852G manufactured by Dow Chemical Co., Ltd.). Mix C3) to 10 parts by weight, high-density polyethylene (D1) to 55 parts by weight, and high-pressure low-density polyethylene (E1) to 35 parts by weight, and use a single-screw extruder (Placo Co., Ltd., diameter 50 mm). A laminated film and a foamed laminate were obtained by the same method as in Example 1 except that the ethylene resin composition (B4, MFR 8.5 g / 10 minutes, density 941 kg / m ³ ) melt-kneaded was used. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 1. The thickness of the foamed layer after foaming, the foamed appearance, and the hot tack property were all good.

Example 5
As the resin for the layer (B), an ethylene / 1-hexene copolymer having an MFR of 20 g / 10 minutes, a density of 920 kg / m ³ , and a molecular weight distribution of 3.5 (trade name Niporon-Z ZM330 manufactured by Toso Co., Ltd.) , C4) to 50 parts by weight, high-density polyethylene (D1) to 40 parts by weight, high-pressure method low-density polyethylene (E1) to 10 parts by weight, single-screw extruder (Placo Co., Ltd. caliber 50 mm) A laminate film and a foamed laminate were obtained by the same method as in Example 1 except that the ethylene resin composition melt-kneaded in (B5, MFR 4.9 g / 10 minutes, density 938 kg / m ³ ) was used. .. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 1. The thickness of the foamed layer after foaming, the foamed appearance, and the hot tack property were all good.

Example 6
As the resin of the layer (B), an ethylene / 1-hexene copolymer having an MFR of 2.0 g / 10 minutes, a density of 930 kg / m ³ , and a molecular weight distribution of 1.7 (trade name Niporon manufactured by Toso Co., Ltd.) ZHF250K, C5) is blended to 10 parts by weight, high-density polyethylene (D1) to 40 parts by weight, and high-pressure low-density polyethylene (E1) to 50 parts by weight, and a single-screw extruder (Placo Co., Ltd. caliber) The laminate film and the foamed laminate were prepared by the same method as in Example 1 except that the ethylene resin composition (B6, MFR 6.2 g / 10 minutes, density 941 kg / m ³ ) melt-kneaded in (50 mm) was used. Obtained. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 1. The thickness of the foamed layer after foaming, the foamed appearance, and the hot tack property were all good.

Example 7
As the resin of the layer (B), 10 parts by weight of ethylene / 1-hexene copolymer (C1), MFR of 20 g / 10 minutes, and density of 966 kg / m ³ are high-density polyethylene (trade name manufactured by Toso Co., Ltd.). Nipolon Hard 1000, D2) is mixed in 80 parts by weight and high-pressure low-density polyethylene (E2) is mixed in 10 parts by weight, and melt-kneaded with a single-screw extruder (Placo Co., Ltd. caliber 50 mm). A laminate film and a foamed laminate were obtained by the same method as in Example 1 except that the material (B7, MFR 12 g / 10 minutes, density 956 kg / m ³ ) was used. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 1. The thickness of the foamed layer after foaming, the foamed appearance, and the hot tack property were all good.

Example 8
As the resin for the layer (A), high-pressure low-density polyethylene (trade name Petrosen 07C03C manufactured by Tosoh Corporation) (A2) having an MFR of 14 g / 10 minutes, a density of 918 kg / m ³ , and an SR of 1.74 is used. A laminated film and a foamed laminate were obtained by the same method as in Example 1 except for the above. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 1. The thickness of the foamed layer after foaming, the foamed appearance, and the hot tack property were all good.

Example 9
As the resin of the layer (A), high-pressure low-density polyethylene (trade name Petrosen 213 manufactured by Toso Co., Ltd.) (A3) having an MFR of 8 g / 10 minutes, a density of 918 kg / m ³ , and an SR of 1.80 is used. A laminated film and a foamed laminate were obtained by the same method as in Example 1 except for the above. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 1. The thickness of the foamed layer after foaming, the foamed appearance, and the hot tack property were all good.

比較例１
（Ｂ）層の樹脂として、エチレン・１−ヘキセン共重合体（Ｃ１）を３重量部、高密度ポリエチレン（Ｄ１）を４０重量部、高圧法低密度ポリエチレン（Ｅ１）を５７重量部になるよう配合し、単軸押出機（プラコー（株）製 口径５０ｍｍ）にて溶融混練したエチレン系樹脂組成物（Ｂ８、ＭＦＲ ６．３ｇ／１０分、密度 ９４０ｋｇ／ｍ^３）を使用した以外は、実施例１と同様の手法によりラミネートフィルム及び発泡積層体を得た。得られたラミネートフィルム・発泡積層体について、発泡層厚み、発泡外観、ホットタック性を評価した。評価の結果を表２に示す。ホットタック性に劣っていた。

Comparative Example 1
As the resin of the layer (B), the ethylene / 1-hexene copolymer (C1) is 3 parts by weight, the high density polyethylene (D1) is 40 parts by weight, and the high pressure method low density polyethylene (E1) is 57 parts by weight. Except for using an ethylene resin composition (B8, MFR 6.3 g / 10 minutes, density 940 kg / m ³ ) that was blended and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). A laminated film and a foamed laminate were obtained by the same method as in Example 1. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 2. It was inferior in hot tackiness.

Comparative Example 2
As the resin of the layer (B), 80 parts by weight of ethylene / 1-hexene copolymer (C5), 10 parts by weight of high-density polyethylene (D1), and 10 parts by weight of high-pressure low-density polyethylene (E2). Except for using an ethylene resin composition (B9, MFR 2.5 g / 10 minutes, density 932 kg / m ³ ) that was blended and melt-kneaded with a single-screw extruder (Placo Co., Ltd., diameter 50 mm). A laminated film and a foamed laminate were obtained by the same method as in Example 1. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 2. The thickness of the foam layer was inferior.

Comparative Example 3
As the resin of the layer (B), 60 parts by weight of ethylene / 1-hexene copolymer (C5) and 40 parts by weight of high-pressure low-density polyethylene (E1) are blended, and a single-screw extruder (Placo Co., Ltd.) ) Laminated film and foamed by the same method as in Example 1 except that the ethylene resin composition (B10, MFR 2.4 g / 10 minutes, density 928 kg / m ³ ) melt-kneaded in (diameter 50 mm) was used. A laminate was obtained. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 2. The thickness of the foam layer was inferior.

Comparative Example 4
As the resin of the layer (B), an ethylene / 1-butene copolymer having an MFR of 30 g / 10 minutes, a density of 912 kg / m3, and a molecular weight distribution of 1.7 (trade name: Lumitac 10L51A, C6 manufactured by Toso Co., Ltd.) 30 parts by weight, high-density polyethylene (D1) to 50 parts by weight, and high-pressure low-density polyethylene (E1) to 20 parts by weight, and melted with a single-screw extruder (Placo Co., Ltd. caliber 50 mm). A laminate film and a foamed laminate were obtained by the same method as in Example 1 except that the kneaded ethylene resin composition (B11, MFR 16 g / 10 minutes, density 940 kg / m ³ ) was used. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 2. It was inferior in hot tackiness.

Comparative Example 5
As the resin of the layer (A), the same method as in Example 1 except that the high pressure method low density polyethylene (E1) having an MFR of 3 g / 10 minutes, a density of 925 kg / m ³ and an SR of 2.02 was used. To obtain a laminated film and a foamed laminate. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 2. It was inferior in foam appearance.

Comparative Example 6
As the resin of the layer (A), high-pressure low-density polyethylene (trade name Petrosen 209, A5 manufactured by Tosoh Corporation) having an MFR of 45 g / 10 minutes, a density of 924 kg / m ³ , and an SR of 1.30 was used. A laminated film and a foamed laminate were obtained by the same method as in Example 1 except for the above. The foamed layer thickness, foamed appearance, and hot tackiness of the obtained laminated film / foamed laminate were evaluated. The evaluation results are shown in Table 2. When the layer (A) was formed, the thickness of the laminate was not stable, and the laminate film 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 (7)

Low-density polyethylene (a) containing at least (A) layer / paper base material layer / (B) layer, where (A) layer satisfies (i) to (ii), and (B) layer is (iii) to (iv) ) Is made of a polyethylene resin (b) satisfying the above conditions.
(I) Melt mass flow rate (MFR) measured by JIS K6922-1 (1997) is 5 g / 10 minutes or more and 30 g / 10 minutes or less (ii) Density measured by JIS K6922-1 (1997) is 910 kg / m. ³ above 930 kg / ^{m 3} or less (iii) JIS K6922-1 density density measured by (1997) was measured by 930 kg / ^{m 3} or more 970 kg / ^{m 3} or less (iv) JIS K6922-1 (1997) of 870kg / ^{m 3} or more 920 kg / ^{m 3} or less is ethylene and having 6 or more alpha-olefin copolymers carbon (hereinafter, ethylene · alpha-olefin copolymer of (c).) the 5 wt% to 70 wt% Including below The foaming according to claim 1, wherein the molecular weight distribution (Mw / Mn) of the ethylene / α-olefin copolymer (c) measured by gel permeation chromatography is 1.3 or more and 3.0 or less. Laminated body for. The polyethylene resin (b) contains 5 parts by weight or more and 70 parts by weight or less of the ethylene / α-olefin copolymer (c), and the density measured by JIS K6922-1 (1997) is 940 kg / m ³ or more and 980 kg /. High-density polyethylene (d) of m ³ or less is 20 parts by weight or more and 80 parts by weight or less, and the melt mass flow rate measured by JIS K6922-1 (1997) is 1 g / 10 minutes or more and 10 g / 10 minutes or less. The low-density polyethylene (e) is a polyethylene-based resin composition (f) ((c), (d) and (e) totaling 100 parts by weight) composed of 10 parts by weight or more and 50 parts by weight or less. The foaming laminate according to claim 1 or 2 . The foaming laminate according to any one of claims 1 to 3 , wherein the α-olefin constituting the ethylene / α-olefin copolymer (c) is either 1-hexene or 1-octene. body. Any of claims 1 to 4, wherein the layer (A) is composed only of high-pressure low-density polyethylene (g) having a swell ratio (SR) of 1.40 or more and less than 1.75 measured at 235 ° C. The foaming laminate according to item 1 . A foamed laminate according to any one of claims 1 to 5, wherein the layer (A) of the foamed laminate is foamed. A heat insulating paper container characterized in that the foamed laminate according to claim 6 is used at least for a body member.