JP2015066758A - Foam laminate sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a foam laminate sheet having improved heat insulation properties and a thermal sense at a touch, when used as a foam insulation sheet or a foam insulation container.SOLUTION: A foam laminate sheet has a resin foam layer having a rugged shape laminated on a substrate. (1) In the resin foam layer, a cross-sectional shape in a thickness direction of the foam laminate sheet is a corrugated plate-like shape. (2) Part or all of a group of projections forming the rugged shape have a gap between the resin foam layer and the substrate.

Description

  The present invention relates to a foamed laminated sheet. The foamed laminated sheet has a foamed resin layer and is useful as foamed wallpaper, various decorative materials, and the like.

  Conventionally, a foam laminated sheet in which at least a foamed resin layer is provided on a substrate has been used as foam wallpaper, various decorative materials, and the like. Moreover, it is used also as a foam heat insulation sheet and a foam heat insulation container using the foam cell of a foam resin layer, and the space | gap provided between the foam resin layer and the base material.

  For example, Patent Document 1 relates to a foam insulation sheet and a foam insulation container.

  Claim 1 of Patent Document 1 states that “a sheet in which a synthetic resin film is laminated on a base paper is heated, and the synthetic resin film is foamed mainly using moisture contained in the base paper to form a foamed surface composed of foam cell groups. Then, vacuum suction is applied to at least a part of the foamed surface to lift a part of the foamed cells from the base paper, and adjacent foamed cells stick together to make the apparent foam height uniform. A foam insulation sheet characterized by the above has been disclosed. Further, claim 4 of Patent Document 1 discloses “a foam insulation container characterized in that a foam insulation sheet is used at least in the body of the container.”

  However, the conventional foam laminate sheet has insufficient heat insulation when used as a foam insulation sheet or a foam insulation container, and the surface of the foam laminate sheet is flat when touched by hand or finger. The feeling of warmth is insufficient, and there is room for further improvement.

JP 2004-58535 A

  An object of this invention is to provide the foaming lamination sheet which the heat insulation at the time of using as a foaming heat insulation sheet or a foaming heat insulation container, and the warm feeling at the time of a contact improved.

  As a result of intensive studies to achieve the above object, the present inventor has found that the above object can be achieved by a foam laminate sheet in which a foam resin layer having a specific shape is laminated on a base material. It came to be completed.

That is, the present invention relates to the following foamed laminated sheet.
1. a foam laminated sheet in which a foamed resin layer having an uneven shape is laminated on a substrate,
(1) The foamed resin layer has a corrugated plate shape in the thickness direction of the foamed laminated sheet,
(2) A part or all of the convex group constituting the concave-convex shape has a gap between the foamed resin layer and the substrate.
A foamed laminated sheet characterized by that.
2. The foamed laminated sheet according to item 1, wherein the concavo-convex shape is formed by continuous adjacency of linear or bent long-grain convex portions.
3. The foamed laminated sheet according to item 2, wherein the long grain-shaped convex portion has a length of 2 to 8 mm.
4. The foamed laminated sheet according to any one of Items 1 to 3, wherein the foamed resin layer has a non-foamed resin layer along the uneven shape on one side or both sides.
5. The foamed laminated sheet according to any one of items 1 to 4, which has a surface protective layer on the outermost surface.

Hereinafter, the foamed laminated sheet of the present invention will be described in detail.
≪Foamed laminated sheet≫
The foamed laminated sheet of the present invention has a foamed resin layer having a concavo-convex shape laminated on a substrate,
(1) The foamed resin layer has a corrugated plate shape in the thickness direction of the foamed laminated sheet,
(2) A part or all of the convex group constituting the concave-convex shape has a gap between the foamed resin layer and the base material.

  The foamed laminated sheet of the present invention having the above features has a corrugated cross-sectional shape in the thickness direction of the foamed resin layer as shown in FIG. 1 and FIG. Has decreased compared to conventional products, and the warmth is improved. In addition, since a part or all of the convex groups constituting the concavo-convex shape have gaps (air layers) as shown in FIG. 1 and FIG. 3, heat insulation is improved as compared with the conventional product. The foam laminate sheet of the present invention can be widely used as a material for a foam heat insulation sheet or a foam heat insulation container.

  Hereinafter, each layer which comprises a foaming lamination sheet is demonstrated.

Base material (fibrous sheet)
It does not limit as a base material, A well-known fiber sheet (backing paper) etc. can be utilized.

  Specifically, wallpaper general paper (pulp-based sheet sized with a known sizing agent); flame-retardant paper (pulp-based sheet treated with a flame retardant such as guanidine sulfamate or guanidine phosphate) ); Inorganic paper containing inorganic additives such as aluminum hydroxide and magnesium hydroxide; fine paper; thin paper; fiber mixed paper (paper made by mixing pulp and synthetic fiber). In addition, what corresponds to a nonwoven fabric is included in the fibrous sheet used for this invention on classification.

Although the basis weight of the substrate is not critical, preferably about 50 to 300 g / m ^2, more preferably about 50~120 g / m ^2.

Foamed resin layer In the foamed laminated sheet of the present invention, a foamed resin layer having an uneven shape is laminated on a substrate.

  The foamed resin layer in the present invention has a concavo-convex shape, the cross-sectional shape in the thickness direction is a corrugated plate shape, and part or all of the convex group constituting the concavo-convex shape is between the foamed resin layer and the substrate. Have voids.

  The corrugated plate shape is as shown in FIGS. 1 and 3, and the height of the corrugated plate shape (the distance from the bottom to the top of the corrugated plate shape) is usually about 1.3 to 2.0 mm. Moreover, the thickness (foaming thickness) of the foamed resin layer constituting the corrugated plate shape is usually about 300 to 800 μm. Furthermore, a part or all (preferably all) of the convex groups constituting the concavo-convex shape have a gap between the foamed resin layer and the substrate, as shown in FIGS. The gap is preferably present in substantially all of the convex group, but it is allowed that a convex part without a gap is included in part from the relationship between the height of the corrugated sheet and the thickness of the foamed resin layer. .

  In the foamed laminated sheet of the present invention, the presence of the voids effectively contributes to the development of excellent heat insulation. The void is formed, for example, by foaming while forming irregularities in the corrugated plate shape when a flat foaming agent-containing resin layer is foamed by heating to form the foamed resin layer.

  FIG. 2 is a surface view showing an example of a specific embodiment of the foamed laminated sheet of the present invention. In this aspect, the concavo-convex shape is formed by continuous adjacency of linear or bent long grain-shaped convex portions (dense together without a gap), and the average length of the long-grain convex portions. Is about 2 to 8 mm. The length indicates the measured value when measuring the distance between the ends in the case of a straight line, and the measured value when measuring the shortest distance between the ends in the case of a bent shape. The observation was performed using

  The foamed resin layer is obtained by foaming the foaming agent-containing resin layer by heating.

  As the resin component contained in the foaming agent-containing resin layer, vinyl chloride resins and olefin resins conventionally used for foamed sheets can be widely used. However, the vinyl chloride resin may cause the plasticizer to bleed over time. Therefore, from the viewpoint of enhancing the durability of the foamed sheet, an olefin resin is preferable to a vinyl chloride resin, and specifically, an ethylene resin is preferably contained.

  The foaming agent-containing resin layer can be formed by a known film forming method such as a T-die film forming method, a calendar film forming method, or a press molding method.

  As the resin component contained in the foaming agent-containing resin layer, vinyl chloride resins and olefin resins conventionally used for wall covering materials can be widely used. However, the vinyl chloride resin may cause the plasticizer to bleed over time. Therefore, from the viewpoint of enhancing the durability of the foamed laminated sheet, an olefin resin is preferable to a vinyl chloride resin, and specifically, an ethylene resin is preferably contained.

  Examples of the ethylene-based resin include not only polyethylene (PE) but also an ethylene copolymer having monomers other than ethylene and components (hereinafter abbreviated as “ethylene copolymer”).

  As the polyethylene, low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE) and the like can be widely used.

  Ethylene copolymers are suitable for extrusion film formation in terms of melting point and MFR. Examples of the ethylene copolymer include ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer ( EEA), ethylene-methyl acrylate copolymer (EMA), ethylene-methacrylic acid copolymer (EMAA), ethylene-α olefin copolymer, and the like. These ethylene copolymers can be used alone or in admixture of two or more. Among these ethylene copolymers, ethylene-vinyl acetate copolymer and ethylene-methyl methacrylate copolymer are particularly preferred. When any one of these is used in combination with one or more other resins, ethylene -The content of the vinyl acetate copolymer and the ethylene-methyl methacrylate copolymer is preferably 70% by mass or more, and more preferably 80% by mass or more.

  Moreover, as for content of monomers other than ethylene, 5-25 mass% is preferable and, as for ethylene copolymer, 9-20 mass% is more preferable. By adopting such a copolymerization ratio, the extrusion film forming property is further enhanced. As a specific example, the ethylene-vinyl acetate copolymer has a vinyl acetate copolymerization ratio (VA amount) of preferably 9 to 25% by mass, and more preferably 9 to 20% by mass. The ethylene-methyl methacrylate copolymer has a methyl methacrylate copolymerization ratio (MMA amount) of preferably 5 to 25% by mass, more preferably 5 to 15% by mass. Further, the ethylene-methacrylic acid copolymer is preferably 2 to 15% by mass, more preferably 5 to 11% by mass as the copolymerization ratio (MAA amount) of acrylic acid.

  In the present invention, the resin component contained in the foaming agent-containing resin layer has an MFR (melt flow rate) measured under conditions of 190 ° C. and a load of 21.18 N described in JIS K 6922, depending on the film forming method. It is preferable that it is 10-25g / 10min. When the MFR is within the above range, there is little increase in temperature when the foaming agent-containing resin layer is formed by extrusion film formation, and the film can be formed in a non-foamed state. It can be printed on any surface and there are few patterns missing. If the MFR is too large, the foaming agent-containing resin layer to be formed may have insufficient scratch resistance due to the resin being too soft.

  As the resin composition for forming the foaming agent-containing resin layer, for example, a resin composition containing the above resin component, inorganic filler, pigment, pyrolytic foaming agent, foaming aid, crosslinking aid and the like can be suitably used. . In addition, stabilizers, lubricants and the like can be used as additives.

  Examples of the thermally decomposable foaming agent include azo series such as azodicarbonamide (ADCA) and azobisformamide; hydrazide series such as oxybenzenesulfonyl hydrazide (OBSH) and paratoluenesulfonyl hydrazide. The content of the pyrolytic foaming agent can be appropriately set according to the type of foaming agent, the expansion ratio, and the like. From the viewpoint of the expansion ratio, it is 5 times or more, preferably about 7 to 10 times, and the pyrolytic foaming agent is preferably about 1 to 20 parts by mass with respect to 100 parts by mass of the resin component.

  The foaming aid is preferably a metal oxide and / or a fatty acid metal salt. For example, zinc stearate, calcium stearate, magnesium stearate, zinc octylate, calcium octylate, magnesium octylate, zinc laurate, calcium laurate, laurin Magnesium acid, zinc oxide, magnesium oxide and the like can be used. About 0.3-10 mass parts is preferable with respect to 100 mass parts of resin components, and, as for content of these foaming adjuvants, about 1-5 mass parts is more preferable.

  When these foaming aids are used in combination with EMAA and ADCA foaming agents, the effect of the foaming aid is impaired by the reaction between the acrylic acid part of EMAA and the metallic foaming aid in the foaming process. There is a problem. Therefore, when EMAA and ADCA foaming agent are used in combination, it is preferable to use a carboxylic acid hydrazide compound as a foaming aid as described in JP-A-2009-197219. At this time, the carboxylic acid hydrazide compound is preferably used in an amount of about 0.2 to 1 part by mass with respect to 1 part by mass of the ADCA foaming agent.

  Examples of the inorganic filler include calcium carbonate, aluminum hydroxide, magnesium hydroxide, antimony trioxide, zinc borate, and a molybdenum compound. By including the inorganic filler, an effect of suppressing see-through, an effect of improving surface characteristics, an effect of suppressing heat generation during combustion, and the like are obtained. The content of the inorganic filler is preferably about 0 to 100 parts by mass and more preferably about 20 to 70 parts by mass with respect to 100 parts by mass of the resin component.

  For pigments, for example, titanium oxide, zinc white, carbon black, black iron oxide, yellow iron oxide, yellow lead, molybdate orange, cadmium yellow, nickel titanium yellow, chrome titanium yellow, iron oxide (valve) ), Cadmium red, ultramarine, bitumen, cobalt blue, chromium oxide, cobalt green, aluminum powder, bronze powder, titanium mica, and zinc sulfide. Examples of organic pigments include aniline black, perylene black, azo (azo lake, insoluble azo, condensed azo), polycyclic (isoindolinone, isoindoline, quinophthalone, perinone, flavantron, anthrapyrimidine, anthraquinone, quinacridone. Perylene, diketopyrrolopyrrole, dibromoanthanthrone, dioxazine, thioindigo, phthalocyanine, indanthrone, halogenated phthalocyanine). The content of the pigment is preferably about 10 to 50 parts by mass, more preferably about 15 to 30 parts by mass with respect to 100 parts by mass of the resin component.

  In the present invention, the foaming agent-containing resin layer may be resin-crosslinked by electron beam irradiation. What is necessary is just to implement according to the method described in the postscript manufacturing method as a method of irradiating an electron beam to a foaming agent containing resin layer, and the method of making it foam.

  In addition, the thickness of the foaming agent-containing resin layer is preferably about 40 to 200 μm, and the thickness of the foamed resin layer is preferably about 300 to 800 μm as described above.

Non-foamed resin layers A and B
The foamed resin layer may have a non-foamed resin layer along the uneven shape on one side or both sides thereof.

  For example, the back surface of the foamed resin layer (the surface on which the fibrous sheet is laminated) may have a non-foamed resin layer B for improving the film formability when the foaming agent-containing resin layer is formed by extrusion. .

  The thickness of the non-foamed resin layer B is not limited, but is preferably about 5 to 50 μm.

  When the foamed laminated sheet of the present invention has the non-foamed resin layer B on the back side of the foamed resin layer, the non-foamed resin layer B has a corrugated plate shape together with the foamed resin layer, and the non-foamed resin layer B and the substrate The gap is formed between the two.

  The non-foamed resin layer A may be formed on the upper surface of the foamed resin layer for the purpose of clarifying the pattern when the pattern layer is formed or improving the scratch resistance of the foamed resin layer.

  Examples of the resin component of the non-foamed resin layer A include polyolefin resins, methacrylic resins, thermoplastic polyester resins, polyvinyl alcohol resins, and fluorine resins. Of these, polyolefin resins are preferred.

  Examples of polyolefin resins include polyethylene (low-density polyethylene (LDPE) or high-density polyethylene (HDPE)), polypropylene, polybutene, polybutadiene, polyisoprene, and other resins, and α-olefin copolymers having 4 or more carbon atoms. (Linear low density polyethylene (LLDPE)), ethylene-acrylic acid copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methacrylic acid copolymer, etc. Examples thereof include at least one of acrylic acid copolymer, ethylene-vinyl acetate copolymer (EVA), saponified ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ionomer and the like. In the present invention, in particular, when a vinyl chloride resin is used as the resin in the foaming agent-containing resin layer, in order to obtain durability of the laminated sheet, the non-foamed resin layer A (particularly an ethylene-vinyl alcohol copolymer layer) is used. It is preferable to form. In addition, "(meth) acrylic acid" means acrylic acid or methacrylic acid, and the same applies to other parts described as (meth).

  The thickness of the non-foamed resin layer A is not limited, but is preferably about 2 to 50 μm.

  In the present invention, an embodiment in which the non-foamed resin layer B, the foamed resin layer, and the non-foamed resin layer A are formed in order from the viewpoint of production described later is also preferable. The non-foamed resin layer B and / or the non-foamed resin layer A may be formed by extrusion film formation, or may be formed by heat laminating each film.

Pattern Pattern Layer In the laminated sheet of the present invention, a pattern pattern layer may be formed on the foamed resin layer, the non-foamed resin layer A, or a primer layer described later, if necessary.

  The pattern layer imparts design properties to the laminated sheet and the foamed laminated sheet. Examples of design patterns include wood grain patterns, stone patterns, sand grain patterns, tiled patterns, brickwork patterns, fabric patterns, leather patterns, geometric figures, characters, symbols, abstract patterns, etc. Can be selected.

  The pattern pattern layer can be formed, for example, by printing a pattern pattern. Examples of printing methods include gravure printing, flexographic printing, silk screen printing, offset printing, and the like. As the printing ink, a printing ink containing a colorant, a binder resin, and a solvent can be used. These inks may be known or commercially available.

  As the colorant, for example, a pigment used in the above-described foaming agent-containing resin layer can be appropriately used.

  The binder resin can be set according to the type of the base sheet. For example, acrylic resin, styrene resin, polyester resin, urethane resin, chlorinated polyolefin resin, vinyl chloride-vinyl acetate copolymer resin, polyvinyl butyral resin, alkyd resin, petroleum resin, ketone resin, epoxy Resin, melamine resin, fluorine resin, silicone resin, fiber derivative, rubber resin and the like.

  Examples of the solvent (or dispersion medium) include petroleum organic solvents such as hexane, heptane, octane, toluene, xylene, ethylbenzene, cyclohexane, and methylcyclohexane; ethyl acetate, butyl acetate, acetic acid-2-methoxyethyl, acetic acid-2 -Ester-based organic solvents such as ethoxyethyl; alcohol-based organic solvents such as methyl alcohol, ethyl alcohol, normal propyl alcohol, isopropyl alcohol, isobutyl alcohol, ethylene glycol, propylene glycol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone Organic solvents such as diethyl ether, dioxane, and tetrahydrofuran; dichloromethane, carbon tetrachloride, trichloroethylene, tetrachloroethylene, etc. Containing organic solvent; and water. These solvents (or dispersion media) can be used alone or in the form of a mixture.

  The thickness of the design pattern layer is different from the type of design pattern, but is generally preferably about 0.1 to 10 μm.

A primer layer may be formed on the primer layer foamed resin layer, the non-foamed resin layer A or the pattern layer, if necessary.

  As the resin contained in the primer layer, for example, acrylic, vinyl chloride-vinyl acetate copolymer, polyester, polyurethane, chlorinated polypropylene, chlorinated polyethylene, and the like can be used. Particularly, acrylic, chlorinated polypropylene, etc. Is desirable.

  Examples of the acrylic include, for example, poly (meth) methyl acrylate, poly (meth) ethyl acrylate, poly (meth) acrylate propyl, poly (meth) acrylate butyl, and (meth) acrylate methyl- (meth) acrylic acid. (Meth) such as butyl copolymer, (meth) ethyl acrylate- (meth) butyl acrylate copolymer, ethylene- (meth) methyl acrylate copolymer, styrene- (meth) methyl acrylate copolymer An acrylic resin made of a homopolymer or a copolymer containing an acrylate ester may be mentioned.

  Polyurethane is a composition having a polyol (polyhydric alcohol) as a main component and an isocyanate as a crosslinking agent (curing agent).

  As the polyol, one having two or more hydroxyl groups in the molecule, for example, polyethylene glycol, polypropylene glycol, acrylic polyol, polyester polyol, polyether polyol and the like are used.

  As the isocyanate, a polyvalent isocyanate having two or more isocyanate groups in the molecule is used. For example, aromatic isocyanate such as 2-4 tolylene diisocyanate, xylene diisocyanate, 4-4 diphenylmethane diisocyanate, or aliphatic (or alicyclic) such as hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated diphenylmethane diisocyanate ) Isocyanates are used.

  The thickness of the primer layer is not limited, but is preferably about 0.1 to 10 μm, more preferably about 0.1 to 5 μm.

Surface protective layer The surface of the foamed resin layer, the non-foamed resin layer A, the pattern layer or the primer layer may have a surface protective layer for the purpose of adjusting the gloss and / or protecting the pattern layer.

  The kind of surface protective layer is not limited. If it is a surface protective layer aiming at gloss adjustment, there exists a surface protective layer containing known fillers, such as a silica, for example. As a method for forming the surface protective layer, a known method such as gravure printing can be employed.

  When forming a surface protective layer for the purpose of surface strength (scratch resistance, etc.), contamination resistance, pattern layer protection, etc. of foamed laminated sheets, those containing ionizing radiation curable resins as resin components are suitable It is. The ionizing radiation curable resin is preferably one that undergoes radical polymerization (curing) by electron beam irradiation.

≪Method for producing foam laminated sheet≫
Although it is not limited as a manufacturing method of a foaming lamination sheet, and what is necessary is just a manufacturing method with which the foaming lamination sheet of the present invention is obtained, as a suitable embodiment, for example,
(1) A step of laminating at least a foaming agent-containing resin layer on a base material, the step of laminating the base material and the foaming agent-containing resin layer so as to be weakly bonded or dotted adhesive
(2) Step 2 of forming the foamed resin layer by heating the foaming agent-containing resin layer,
The manufacturing method which has this.

  In the above production method, in particular, in step 1, the base material and the foaming agent-containing resin layer are laminated so as to be weakly bonded or dotted, so that the foaming agent-containing resin layer is foamed by heating. A predetermined uneven shape can be formed by alternately forming a portion where the material and the foamed resin layer are bonded (the bottom of the corrugated plate shape) and a convex portion (the top of the corrugated plate shape).

  The degree of weak adhesion is preferably such an adhesive force that the base material is peeled without being destroyed when the adhesive interface between the foaming agent-containing resin layer and the base material is peeled off. Specifically, when the substrate is a fibrous sheet, it is preferable that the substrate is peeled without being taken off. In the case of dot adhesion, the base material and the foaming agent-containing resin layer are preferably point-bonded by a plurality of points arranged regularly or irregularly. It can be appropriately set according to the size and shape of the convex group constituting the uneven shape.

  When the foaming agent-containing resin layer has a non-foamed resin layer on one side or both sides, co-extrusion film formation using a T-die extruder is suitable. For example, in the case of having non-foamed resin layers on both sides, a multi-manifold type T die capable of simultaneously forming three layers by simultaneously extruding molten resins corresponding to the three layers can be used.

  In addition, when an inorganic filler is contained in the resin composition forming the foaming agent-containing resin layer and the foaming agent-containing resin layer is formed by extrusion film formation, an extrusion port (so-called die) of the extruder is used. Inorganic filler residues (so-called eyes and eyes) are easily generated, and this tends to be a foreign matter on the surface of the foaming agent-containing resin layer. Therefore, when an inorganic filler is included in the resin composition forming the foaming agent-containing resin layer, three layers are co-extruded to form a resin layer that does not contain an inorganic filler on both sides as described above. It is preferable. That is, it is possible to suppress the occurrence of the above-mentioned corners by co-extrusion film formation in a mode in which the foaming agent-containing resin layer is sandwiched between non-foamed resin layers.

  After forming the foaming agent-containing resin layer, electron beam irradiation may be performed. Thereby, the resin component can be cross-linked to adjust the surface strength, foaming characteristics, etc. of the foamed resin layer. The energy of the electron beam is preferably about 150 to 250 kV, more preferably about 175 to 200 kV. The irradiation amount is preferably about 10 to 100 kGy, and more preferably about 10 to 50 kGy. A known electron beam irradiation apparatus can be used as the electron beam source.

  On the foaming agent-containing resin layer, if necessary, a pattern layer and a primer layer are formed in any order, and if necessary, a surface protective layer is formed to form a laminated sheet, and then heat-treated. A foaming laminated sheet is obtained by making the foaming agent-containing resin layer into a foamed resin layer. Each of these layers can be laminated by combining coating such as printing and coating, extrusion film formation and the like, and coating such as printing and coating can be performed according to a conventional method.

  The heat treatment conditions may be any conditions as long as the foamed resin layer is formed by the decomposition of the pyrolytic foaming agent. The heating temperature is preferably about 210 to 240 ° C., and the heating time is preferably about 20 to 80 seconds. Further, when an embossed pattern is added, it is carried out by a known means such as pressing an embossed plate.

  As shown in FIGS. 1 and 3, the foamed laminated sheet of the present invention has a corrugated cross-sectional shape in the thickness direction of the foamed resin layer. Compared to the decrease, the feeling of warmth is improved. In addition, since a part or all of the convex groups constituting the concavo-convex shape have gaps (air layers) as shown in FIG. 1 and FIG. 3, heat insulation is improved as compared with the conventional product. The foam laminate sheet of the present invention can be widely used as a material for a foam heat insulation sheet or a foam heat insulation container.

It is a cross-sectional schematic diagram which shows an example of the layer structure of the foaming lamination sheet of this invention. It is a surface view which shows an example of the uneven | corrugated shape of the foaming lamination sheet of this invention. It is a figure which shows an example of the cross-sectional shape (corrugated sheet shape) of the foaming resin layer of the foaming lamination sheet of this invention.

  The present invention will be specifically described below with reference to examples and comparative examples. However, the present invention is not limited to the examples.

Example 1 and Comparative Examples 1-2
≪Preparation of resin composition containing foaming agent≫
Resin compositions having the compositions shown in Table 1 below were prepared by kneading.

(Example 1)
The resin composition was press molded with a hydraulic press to obtain a 110 μm thick resin sheet.

Next, the resin sheet was press laminated at 120 ° C. and 1 MPa on a 65 g / m ² backing paper (CP65PDK, manufactured by Chuetsu Pulp Industries Co., Ltd.) to form a foaming agent-containing resin layer. The adhesive strength between the resin sheet and the foaming agent-containing resin layer was such that the fibers of the backing paper were not removed when the resin sheet was peeled off.

  Next, after electron beam irradiation (195KV 30KGy) was performed on the resin surface, the resin layer was foamed for 35 seconds in a gear oven at 220 ° C. to obtain a foamed laminated sheet.

The foamed resin layer was formed in a corrugated shape (cross-sectional shape) on the substrate, the thickness of the foamed resin layer was 400 to 800 μm, and the height of the corrugated shape of the foamed resin layer was 1.5 to 1.7 mm.
(Comparative Example 1)
A foamed laminated sheet was obtained in the same manner as in Example 1 except that the press lamination conditions were 120 ° C. and 10 MPa. The adhesive strength between the resin sheet and the foaming agent-containing resin layer was increased as compared with Example 1 to such an extent that the fibers of the backing paper were removed when the resin sheet was peeled off.

The foamed resin layer was formed flat on the substrate, and the foamed resin layer was 700 to 800 μm thick.
(Comparative Example 2)
A laminated sheet was obtained in the same manner as in Example 1 except that the foaming treatment was not performed.

The resin layer thickness was 110 μm.
≪Evaluation of each sheet≫
The heat insulation performance of the foamed laminated sheet and the laminated sheet was evaluated.

  Specifically, using the program hot plate “EC HOTPLATE EC-1200NP (manufactured by AS ONE)”, the hot plate steel plate heated to 80 ° C. is brought into contact with the resin surface facing upward, and after 20 seconds the resin The surface temperature was measured from above the surface with a non-contact type thermometer “IT2-80 (manufactured by Keyence)”.

The evaluation criteria for the surface temperature were as follows.
○: The temperature difference from the hot plate temperature was 15 ° C or more △: The temperature difference from the hot plate temperature was 10 ° C or more and less than 15 ° C ×: The temperature difference from the hot plate temperature was 10 ° C Also, the time required for touching the resin surface of the sheet placed on the hot plate with a finger until it could not be touched (the time when finger can be carved) was measured.

Claims (5)

A foamed laminated sheet in which a foamed resin layer having an uneven shape is laminated on a substrate,
(1) The foamed resin layer has a corrugated plate shape in the thickness direction of the foamed laminated sheet,
(2) A part or all of the convex group constituting the concave-convex shape has a gap between the foamed resin layer and the substrate.
A foamed laminated sheet characterized by that.   2. The foamed laminated sheet according to claim 1, wherein the concavo-convex shape is formed by continuous adjacency of linear or bent long-grain convex portions.   3. The foamed laminated sheet according to claim 2, wherein the long grain-shaped convex portion has a length of 2 to 8 mm.   The foamed laminated sheet according to any one of claims 1 to 3, wherein the foamed resin layer has a non-foamed resin layer along the uneven shape on one side or both sides.   The foamed laminated sheet according to any one of claims 1 to 4, which has a surface protective layer on the outermost surface.

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