JP2019177654A - Laminated sheet and foamed laminated sheet - Google Patents

Abstract

To provide a foamed laminated sheet that has excellent scratch resistance and embossing properties, suppresses curling at low-temperature environment, and has excellent winter workability, and a laminated sheet useful for making the foamed laminated sheet.SOLUTION: A laminated sheet has, on a base material 1, at least a foaming agent-containing resin layer 3, and a surface protective layer 7 having a surface protective layer A7-A and a surface protective layer B7-B, wherein the surface protective layer A has a resin with a glass transition temperature of 0°C or less, and the surface protective layer B contains an ethylene-(meth) acrylic acid copolymer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a laminated sheet and a foam laminated sheet.

  The foamed laminated sheet has a foamed resin layer and is useful as foamed wallpaper, various decorative materials, and the like. Moreover, the said laminated sheet means the state (what is called an unfoamed raw material) before foaming of the said foaming laminated sheet.

  Conventionally, a foamed laminated sheet in which at least a foamed resin layer and a surface protective layer are provided on a substrate is known, and is used as foamed wallpaper, various decorative materials, and the like. The foamed resin layer is generally formed by foaming a foaming agent-containing resin layer, and the foaming agent-containing resin layer and the surface protective layer are a coating method such as comma coating, a calendar method in which the resin composition is stretched and laminated in a sheet shape. It is known to form by extrusion film formation using an extruder such as a T-die.

For example, Patent Document 1 states that “a method for producing a laminated sheet in which at least a foaming agent-containing resin layer and a surface protective layer are sequentially formed on a substrate,
(1) The surface protective layer is composed of a single layer or multiple layers, and at least one layer constituting the surface protective layer is a layer containing polyethylene and / or an ethylene copolymer,
(2) Step 1 of forming the foaming agent-containing resin layer on the substrate;
(3) Step 2 of forming the surface protective layer on the foaming agent-containing resin layer by extrusion film formation,
(4) A method for producing a laminated sheet, comprising the step 3 of crosslinking the polyethylene and / or the ethylene copolymer by irradiating an electron beam from the surface protective layer side. Is disclosed (claim 1 etc.).

  In the method for producing a laminated sheet of Patent Document 1, at least one layer constituting the surface protective layer is a layer containing polyethylene and / or an ethylene copolymer, and the surface protective layer is formed by extrusion film formation. Is used to crosslink the resin component of the surface protective layer to obtain a laminated sheet with good production stability and excellent stain resistance and scratch resistance (paragraph [0014]).

  Moreover, when the surface protective layer is a multilayer, a layer containing a resin other than polyethylene and / or ethylene copolymer may be combined as a resin layer other than a layer containing polyethylene and / or ethylene copolymer. (Paragraph [0059]). And a lamination sheet turns into a foaming lamination sheet by foaming a foaming agent containing resin layer, and is used for uses, such as a foam wallpaper and a decoration material.

JP 2012-213939 A JP 2012-052413 A JP 2001-058375 A

  However, the foamed laminated sheet described in Patent Document 1 has a low embossing moldability compared to a foamed laminated sheet that does not have a surface protective layer, and curling is likely to occur in a low-temperature environment, resulting in poor winter workability. Is a problem.

In this regard, Patent Document 2 discloses that a foamed resin layer mainly composed of a foaming agent and an olefinic resin or an acrylic resin, a pattern layer, and a heat-melted non-halogen thermoplastic resin are extruded onto a base material layer. In order to improve the workability of the wall covering sheet provided with the surface protective layer formed in order by the construction method, the bending elastic modulus of the surface protective layer is set to 1.0 × 10 ^{4 to} 2.0 × 10 ⁴ kgf / cm ² . Although it has been proposed to adjust, curl suppression in a low temperature environment is not mentioned, and there is still room for improvement in embossing formability by adjusting the flexural modulus.

  In Patent Document 3, a foamed resin layer mainly composed of a foaming agent and an olefin resin or an acrylic resin, a pattern layer, and a surface protective layer made of a thermoplastic resin are sequentially provided on the base material layer. In order to improve the workability of the wall covering sheet, it has been proposed that the surface protective layer is made of a non-halogen thermoplastic resin and an amorphous resin. There is still room for improvement in scratch resistance, and no mention is made of embossing moldability.

  The present invention has been completed in view of the above problems of the prior art, and is a foamed laminated sheet having at least a foamed resin layer and a surface protective layer on a base material, and is excellent in scratch resistance and embossability. At the same time, it is an object of the present invention to provide a foamed laminated sheet in which curling in a low temperature environment is suppressed and excellent in winter workability, and a laminated sheet useful for producing the foamed laminated sheet.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventor achieved the above object by having a surface protective layer having a multilayer structure and having a surface protective layer A and a surface protective layer B containing a specific resin component. The inventors have found that this can be achieved and have completed the present invention.

That is, this invention relates to the following laminated sheet and foam laminated sheet.
1. A laminated sheet having at least a foaming agent-containing resin layer and a surface protective layer on a substrate,
(1) The surface protective layer has a multilayer structure, and has a surface protective layer A and a surface protective layer B from the side close to the substrate.
(2) The surface protective layer A contains a resin having a glass transition temperature of 0 ° C. or lower, and the surface protective layer B contains an ethylene- (meth) acrylic acid copolymer.
A laminated sheet characterized by that.
2. Item 2. The laminated sheet according to Item 1, wherein the resin having a glass transition temperature of 0 ° C or lower has a melting point of 60 to 100 ° C.
3. Item 3. The laminated sheet according to Item 1 or 2, wherein the ethylene- (meth) acrylic acid copolymer has a melting point of 60 to 100 ° C.
4). The ratio of the thickness of the surface protective layer A and the surface protective layer B is any one of the above items 1 to 3, wherein the surface protective layer A: the surface protective layer B = 0.5 to 5: 1. Laminated sheet.
5. Item 5. The laminated sheet according to any one of Items 1 to 4, wherein the foaming agent-containing resin layer has a non-foamed resin layer on one side or both sides.
6). A foam laminated sheet having at least a foamed resin layer and a surface protective layer on a substrate,
(1) The surface protective layer has a multilayer structure, and has a surface protective layer A and a surface protective layer B from the side close to the substrate.
(2) The surface protective layer A contains a resin having a glass transition temperature of 0 ° C. or lower, and the surface protective layer B contains an ethylene- (meth) acrylic acid copolymer.
A foamed laminated sheet characterized by that.
7). Item 7. The foamed laminated sheet according to Item 6, having an embossed uneven pattern on the front surface.

  The laminated sheet of the present invention has a surface protective layer having a multilayer structure, and has a surface protective layer A and a surface protective layer B containing a specific resin component, thereby foaming the foaming agent-containing resin layer to obtain a foamed laminated sheet. When used as, it is excellent in scratch resistance and embossing moldability and curling in a low temperature environment is suppressed, and it is excellent in winter workability. Such a foamed laminated sheet of the present invention can be widely used as various decorative materials including foamed wallpaper.

It is a cross-sectional schematic diagram which shows an example of the laminated constitution of the lamination sheet of this invention. It is a cross-sectional schematic diagram which shows an example of the layer structure of the foaming lamination sheet of this invention.

Hereinafter, the laminated sheet and the foamed laminated sheet of the present invention will be described in detail.
≪Laminated sheet≫
The laminated sheet of the present invention has at least a foaming agent-containing resin layer and a surface protective layer on the substrate, (1) the surface protective layer has a multilayer structure, and the surface protective layer from the side close to the substrate. A and surface protective layer B,
(2) The surface protective layer A contains a resin having a glass transition temperature of 0 ° C. or lower, and the surface protective layer B contains an ethylene- (meth) acrylic acid copolymer.
It is characterized by that.

  The laminated sheet of the present invention having the above characteristics has a surface protective layer having a multilayer structure, and has a surface protective layer A and a surface protective layer B containing a specific resin component, thereby causing the foaming agent-containing resin layer to foam. When used as a foamed laminated sheet, it is excellent in scratch resistance and embossability, and curling in a low temperature environment is suppressed, so that it is excellent in winter workability. The foamed laminated sheet of the present invention can be widely used as various decorative materials including foamed wallpaper.

  Hereinafter, each layer which comprises a lamination sheet is demonstrated. In this specification, the direction in which the foaming agent-containing resin layer is laminated as viewed from the base material is referred to as “upper” or “front surface”, and the foaming agent-containing resin layer is laminated from the base material. The side opposite to the direction in which it is placed is referred to as “lower” or “back surface” (the same applies to the foamed laminated sheet described later).

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,} about 50~130g / ^{m 2} is more preferable.

Foaming agent-containing resin layer The laminated sheet of the present invention has a foaming agent-containing resin layer on a substrate.

  As the resin component contained in the foaming agent-containing resin layer, vinyl chloride resins and olefin resins conventionally used for foamed laminated sheets can be widely used, but vinyl chloride resins 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 ethylene (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.

  The ethylene copolymer is suitable for extrusion film formation from the viewpoint of melting point and MVR (melt volume flow rate). Examples of the ethylene copolymer include an ethylene-vinyl acetate copolymer (EVA), an ethylene-methyl methacrylate copolymer (EMMA), an ethylene-acrylic acid copolymer (EAA), and an 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, at least one of EVA, EMMA, and EMAA is particularly preferable. When at least one of EVA, EMMA, and EMAA is used in combination with one or more other resins, EVA, EMMA, and 70 mass% or more is preferable and, as for content of at least 1 sort (s) of EMAA, 80 mass% or more is more preferable.

  Moreover, 5-25 mass% is preferable as content of monomers other than ethylene, 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, more preferably 9 to 20% by mass. Moreover, 5-25 mass% is preferable as a copolymerization ratio (MMA amount) of a methyl methacrylate, and, as for the ethylene-methyl methacrylate copolymer, 5-15 mass% is more preferable. Moreover, 2-15 mass% is preferable as an acrylic acid copolymerization ratio (MAA amount) of an ethylene-methacrylic acid copolymer, and 5-11 mass% is more preferable.

The resin component contained in the foaming agent-containing resin layer, 130 ° C. according to JIS K7210 B method, it is preferred MVR measured under a load of 21.18N is 10 to 40 cm ^3/10 min. If the MVR is too large, the resin is too soft and the resulting resin layer may have insufficient scratch resistance. In addition, all MVR in this specification is the value measured on the said conditions.

  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 1.5 times or more, preferably about 3 to 7 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. .

  In the present invention, a foaming aid can be used in combination with the pyrolytic foaming agent.

  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, EMAA and ADCA are used in combination, there is a problem that the effect as a foaming aid is impaired by the reaction of the carboxyl group part of EMAA and the metal foaming aid during foaming. is there. For this reason, when EMAA and ADCA 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, it is preferable to use about 0.2-1 mass part of carboxylic acid hydrazide compounds with respect to 1 mass part of ADCA.

  In addition to the above components, an inorganic filler, a pigment, a stabilizer, a lubricant, and the like can be added to the resin composition forming the foaming agent-containing resin layer as additives.

  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. About 0-100 mass parts is preferable with respect to 100 mass parts of resin components, and, as for content of an inorganic filler, about 20-70 mass parts is more preferable.

  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. Organic pigments include, for example, 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). These pigments can be used alone or in admixture of two or more. About 1-50 mass parts is preferable with respect to 100 mass parts of resin components, and, as for content of a pigment, about 2-30 mass parts is more preferable.

  In the present invention, the foaming agent-containing resin layer may be resin-crosslinked. As a method of crosslinking the resin, there are a method using a peroxide and a method of crosslinking by irradiating an electron beam. 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 this invention, it is preferable to set 130 degreeC MVR of the resin composition (compound) which forms a foaming agent containing resin layer to 16 cm < ³ > / 10 minutes or more. Thereby, the resin composition has high fluidity, and a foaming agent-containing resin layer can be suitably formed by extrusion film formation.

The upper limit of the MVR is not particularly limited so long as capable of film formation, it preferably less 25 cm ^3/10 min. By the MVR and 16~25cm ^3/10 min, with suitably form a blowing agent-containing resin layer by extrusion casting, it is possible to further improve the foaming properties.

  The thickness of the foaming agent-containing resin layer is preferably about 40 to 100 μm.

Non-foamed resin layers A and B
The foaming agent-containing resin layer may have a non-foamed resin layer on one side or both sides.

  For example, the back surface (surface on which the fibrous sheet is laminated) of the foaming agent-containing resin layer may have a non-foamed resin layer B (adhesive resin layer) for the purpose of improving the adhesive strength with the fibrous sheet. .

  The resin component of the adhesive resin layer is not particularly limited, but an ethylene-vinyl acetate copolymer (EVA) is preferable. EVA can be a known or commercially available one. In particular, the vinyl acetate component (VA component) is preferably 10 to 46 mass%, more preferably 15 to 41 mass%.

  The thickness of the adhesive resin layer is not limited, but is preferably about 3 to 50 μm, more preferably about 5 to 20 μm.

  The non-foamed resin layer A may be formed on the upper surface of the foaming agent-containing resin layer for the purpose of clarifying the pattern when forming the pattern layer 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, fluorine resins, and the like, among which polyolefin resins are preferable.

  Examples of polyolefin resins include polyethylene (low density polyethylene (LDPE) or high density polyethylene (HDPE)), polypropylene, polybutene, polybutadiene, polyisoprene, and other resins, and ethylene and α-olefin having 4 or more carbon atoms. Polymers (linear low density polyethylene (LLDPE)), ethylene-acrylic acid copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methacrylic acid copolymer and other ethylene ( Examples include at least one of a (meth) acrylic acid copolymer, an ethylene-vinyl acetate copolymer (EVA), a saponified ethylene-vinyl acetate copolymer, an ethylene-vinyl alcohol copolymer, and an ionomer.

  In the present invention, in particular, when a vinyl chloride resin is used as the resin in the foaming agent-containing resin layer, the non-foamed resin layer A (especially an ethylene-vinyl alcohol copolymer layer) is used to obtain durability of the laminated sheet. 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, and more preferably about 5 to 20 μm.

  In the present invention, an embodiment in which the non-foamed resin layer B, the foaming agent-containing resin layer, and the non-foamed resin layer A are formed in order from the viewpoint of production described later is also preferable.

Pattern Pattern Layer In the laminated sheet of the present invention, a pattern pattern layer may be formed on a resin layer (foaming agent-containing resin layer, non-foamed resin layer A, etc.) 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 the design pattern include a grain pattern, a stone pattern, a grain pattern, a tiled pattern, a brickwork pattern, a cloth pattern, a leather pattern, a geometric figure, a character, a symbol, an abstract pattern, a flower pattern, etc. You can choose according to your purpose.

  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, 2-methoxyethyl acetate, and 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; ether organic solvents such as diethyl ether, dioxane, tetrahydrofuran; dichloromethane, carbon tetrachloride, trichloroethylene, tetrachloroethylene Chlorinated organic solvents; 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 resin layer (foaming agent-containing resin layer, non-foamed resin layer A, etc.) 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 isocyanates such as 2,4-tolylene diisocyanate, xylene diisocyanate, 4,4-diphenylmethane diisocyanate, or aliphatics (or fats such as hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated diphenylmethane diisocyanate, etc. Cyclic) isocyanates are used.

  Although the thickness of a primer layer is not limited, about 0.1-10 micrometers is preferable and about 0.1-5 micrometers is more preferable.

Surface Protective Layer The laminated sheet of the present invention has a surface protective layer on the substrate together with the foaming agent-containing resin layer.

  The surface protective layer is provided on the surface of a resin layer (a foaming agent-containing resin layer, a non-foamed resin layer A, etc.), a pattern layer or a primer layer. By having specific surface protective layer A and surface protective layer B from the near side, the foamed laminated sheet as the final product is excellent in scratch resistance and embossing formability, and curling in a low temperature environment is suppressed. The effect that it is excellent in property is acquired. The surface protective layer can also be provided with a gloss adjustment and / or effect of protecting the pattern layer.

  An example of a suitable layer structure of the laminated sheet of the present invention is shown in FIG. In FIG. 1, a non-foamed resin layer B <b> 2, a foaming agent-containing resin layer 3, a non-foamed resin layer A <b> 4, a design pattern layer 5, and a primer layer 6 are sequentially laminated on the substrate 1, and surface protection is provided on the primer layer 6. Layer 7 (surface protective layer 7-A and surface protective layer 7-B from the base material side) is laminated.

  The surface protective layer A contains a resin having a glass transition temperature of 0 ° C. or lower. Thereby, the surface protective layer A has a role which gives emboss shaping property and winter workability based on curling in a low-temperature environment especially to a foaming lamination sheet.

  The resin having a glass transition temperature of 0 ° C. or lower is not limited, but polyethylene, ethylene-vinyl acetate copolymer, ethylene-vinyl acetate- (meth) acrylic acid copolymer (a terpolymer, Hereinafter, it may be at least one kind of “terpolymer”. The surface protective layer A includes a resin having a glass transition temperature of 0 ° C. or lower, thereby imparting embossability to the foamed laminated sheet and winter workability based on curling in a low temperature environment. There is a role. As the resin having a glass transition temperature of 0 ° C. or lower, among the resins listed above, terpolymers are preferable, and ethylene-vinyl acetate-methacrylic acid copolymers are particularly preferable. The terpolymer can be appropriately selected from commercially available products.

  Resins having a glass transition temperature of 0 ° C. or lower are required to have physical properties that are easily softened even at low temperatures in winter and have a relatively low melting point. From this point of view, the glass transition temperature is more preferably −5 ° C. or lower among 0 ° C. or lower. The melting point is preferably 60 to 100 ° C, more preferably 70 to 90 ° C.

  In addition, the glass transition temperature in this specification is the value determined by the measurement of dynamic viscoelasticity. Moreover, the melting point in this specification is a value measured by DSC.

  The resin component of the surface protective layer A may be substantially composed only of a resin having a glass transition temperature of 0 ° C. or lower, but other resin components (that is, resins having a glass transition temperature exceeding 0 ° C.) are used in combination. In this case, the content of the resin having a glass transition temperature of 0 ° C. or less in 100% by mass of the resin component is preferably 80% by mass or more so that a resin having a glass transition temperature of 0 ° C. or less is a main component. 90 mass% or more is more preferable. Examples of the resin that can be used in combination include at least one of polybutene, polybutadiene, ethylene- (meth) acrylic acid copolymer, ionomer, and the like.

  Further, the surface protective layer A may contain additives such as anti-mold agents, antistatic agents, antibacterial agents and the like.

  The surface protective layer B contains an ethylene- (meth) acrylic acid copolymer (a binary copolymer, hereinafter also referred to as “binary copolymer”). The surface protective layer B has a role of particularly imparting scratch resistance to the foamed laminated sheet by containing the binary copolymer. Among the binary copolymers, an ethylene-methacrylic acid copolymer (EMAA) is preferable. The binary copolymer can be appropriately selected from commercially available products.

  The binary copolymer is required to have a melting point advantageous for embossability, and the melting point is preferably 60 to 100 ° C, and more preferably 70 to 90 ° C.

  The resin component of the surface protective layer B may be substantially composed only of the binary copolymer, but when the other resin component is used in combination, the binary copolymer is a main component. The content of the binary copolymer in 100% by mass of the resin component is preferably 80% by mass or more, and more preferably 90% by mass or more. Examples of the resin that can be used in combination include at least one of polyethylene and ethylene-vinyl acetate copolymer.

  Further, the surface protective layer B may contain additives such as anti-mold agents, antistatic agents and antibacterial agents.

  In the present invention, the plurality of surface protective layers are arranged in the order of the surface protective layer A and the surface protective layer B from the side close to the substrate. In order to effectively obtain the scratch resistance, embossability of the foamed laminated sheet, and winter workability based on curling in a low temperature environment, the ratio of the thickness of the surface protective layer A and the surface protective layer B is: Although not limited, surface protective layer A: surface protective layer B = 0.5-5: 1 is preferable, and 1-3: 1 are more preferable.

  The surface protective layer having a plurality of structures may be composed of two layers of the surface resin layers A and B, but a so-called overcoat layer may be provided as the outermost layer of the surface protective layer. For example, the overcoat layer preferably contains an ionizing radiation curable resin as a resin component. The ionizing radiation curable resin is preferably one that undergoes radical polymerization (curing) by electron beam irradiation.

  When the purpose of adjusting the gloss is also imparted to the surface protective layer, a known filler such as silica can be added to at least one of the surface protective layers A and B and the above-described overcoat layer.

  As a method for forming the surface protective layer, a known method such as gravure printing can be adopted. However, when the surface protective layers A and B are simultaneously formed, the surface protective layer is formed by extrusion film formation using an extruder such as a T die. It is preferable to do.

An embossed pattern may be provided on the front surface of the embossed laminated sheet or the foamed laminated sheet. In this case, what is necessary is just to emboss from the uppermost surface layer (opposite side to the fibrous sheet). Embossing can be performed by known means such as pressing an embossed plate. With the laminated sheet or foamed laminated sheet of the present invention, a desired embossed pattern can be formed by pressing the embossed plate after heat softening the front surface of the surface protective layer.

Examples of the embossed pattern include a wood grain plate conduit groove, a stone plate surface unevenness, a cloth surface texture, a satin texture, a sand texture, a hairline, a geometric pattern, a multi-row groove, and a contour pattern.
≪Foamed laminated sheet≫
The foamed laminated sheet of the present invention can be obtained by foaming the foaming agent-containing resin layer of the laminated sheet. That is, it has at least a foamed resin layer and a surface protective layer on the substrate,
(1) The surface protective layer has a multilayer structure, and has a surface protective layer A and a surface protective layer B from the side close to the substrate.
(2) The surface protective layer A contains a resin having a glass transition temperature of 0 ° C. or lower, and the surface protective layer B contains an ethylene- (meth) acrylic acid copolymer.
It is characterized by that.

An example of a suitable layer structure of the foamed laminated sheet of the present invention is shown in FIG. In FIG. 2, a non-foamed resin layer B <b> 2, a foamed resin layer 3 ′, a non-foamed resin layer A <b> 4, a design pattern layer 5, and a primer layer 6 are sequentially laminated on the base material 1. 7 (surface protective layer 7-A and surface protective layer 7-B from the base material side) are laminated. Moreover, the embossed uneven | corrugated pattern 8 is provided in the outermost surface side of the foaming lamination sheet.
≪Laminated sheet and foamed laminated sheet manufacturing method≫
As a manufacturing method of a lamination sheet, the manufacturing method which laminate | stacks the said foaming agent containing resin layer and the said surface protective layer at least on a base material is mentioned, for example.

  Moreover, as a manufacturing method of a foaming lamination sheet, in the manufacturing method of a lamination sheet, after laminating | stacking the said foaming agent containing resin layer and the said surface protection layer, the said foaming agent containing resin layer is foamed by heat processing, and a foaming resin layer is used. The manufacturing method to do is mentioned.

  When the foaming agent-containing resin layer has a non-foamed resin layer on one side or both sides, the non-foamed resin layer B and / or the non-foamed resin layer A may be formed by extrusion film formation. Although it may be formed by heat laminating, co-extrusion film formation by a T-die extruder is suitable. For example, in the case of having non-foamed resin layers on both surfaces, 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.

  The resin composition for forming the foaming agent-containing resin layer contains an inorganic filler, and when the foaming agent-containing resin layer is formed by extrusion film formation, the extrusion composition (so-called die lip) of the extruder is inorganic. A filler residue (so-called eyes) is likely to be 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, it is preferable to form a three-layer coextrusion film so that the non-foamed resin layer does not contain an inorganic substance. That is, it is possible to suppress the occurrence of the eyes by co-extrusion film formation in a mode in which the foaming agent-containing resin layer is sandwiched between non-foamed resin layers not containing an inorganic substance.

  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 an arbitrary order, then a surface protective layer is formed into a laminated sheet, and then heat-treated to form a foaming agent-containing resin layer By forming a foamed resin layer, a foamed laminated sheet can be obtained. Taking the laminated sheet shown in FIG. 1 as an example, each layer can be laminated by combining printing, coating and other coatings, extrusion film formation, and the like, and coating such as printing and coating can be carried out according to conventional methods.

  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 25 to 80 seconds. Further, when an embossed pattern is added, it is carried out by a known means such as pressing an embossed plate.

  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
≪Preparation of foam laminated sheet≫
Using a T-die extruder capable of filming three types and three layers, the resin layer is made to have a thickness of 5 μm, 50 μm and 5 μm in the order of non-foamed resin A, foaming agent-containing resin layer and non-foamed resin B. Was extruded to form a film. Extrusion cylinder temperature: 120 ° C., T-die temperature was 120 ° C.

Next, three types and three layers of resin layers were laminated on a 65 g / m ² backing paper (WK-665 KJ special paper) using a laminating roll so that the non-foamed resin layer B would come.

The material of each layer was as follows.
Foaming agent-containing resin layer: 100 parts by mass of ethylene-methacrylic acid copolymer (Mitsui / DuPont Polychemical, binary copolymer “N1110H”) and 30 parts by mass of titanium dioxide (“Taipaque CR-63” manufactured by Ishihara Sangyo) , 20 parts by mass of calcium carbonate (“Whiteon H” manufactured by Toyo Fine Chemical), 5 parts by mass of pyrolytic foaming agent (“Vinhole AC # 3” manufactured by Eiwa Kasei Kogyo), foaming aid (“ADHS” manufactured by Otsuka Chemical) 4 A mixture of parts by mass,
Non-foamed resin A: ethylene-methacrylic acid copolymer (“N1560” manufactured by Mitsui DuPont Polychemical)
Non-foamed resin B: ethylene-vinyl acetate copolymer (“EV150” manufactured by Mitsui DuPont Polychemical).

  Next, after the non-foamed resin layer A was subjected to corona treatment, a pattern layer was formed.

  Next, using a T-die extruder capable of forming two types and two layers, the surface protective layer B (upper layer) and the surface protective layer A (lower layer) are extruded in the order of 4 μm and 8 μm in thickness. A film was formed and laminated on the non-foamed resin layer A. Film formation was carried out at an extrusion cylinder temperature of 190 ° C. and a T-die temperature of 190 ° C.

  As the material for the surface protective layer A, an ethylene-vinyl acetate-methacrylic acid copolymer (Mitsui / DuPont Polychemical, ternary copolymer “N035C”, melting point 86 ° C., glass transition temperature −10 ° C.) is used. As the material for the surface protective layer B, an ethylene-methacrylic acid copolymer (Mitsui DuPont Polychemical, binary copolymer “N1560”, melting point 90 ° C., glass transition temperature 24 ° C.) was used.

  Next, an electron beam curable urethane acrylate resin was applied on the surface protective layer B, and an electron beam (190 kV, 50 kGy) was applied thereon to obtain a laminated sheet.

  Next, the laminated sheet is heated in an oven at 220 ° C. for 40 seconds to foam the foaming agent-containing resin layer, and then reheated and pressed on the embossed plate to form a desired foamed laminate having a concavo-convex pattern on the surface. A sheet was obtained.

Example 2
Of the surface protective layer of Example 1, a foamed laminated sheet was obtained in the same manner as in Example 1 except that the lower layer was formed with a thickness of 4 μm and the upper layer was formed with a thickness of 8 μm.

Example 3
Of the surface protective layer of Example 1, the material of the surface protective layer B (upper layer) was composed of an ethylene-methacrylic acid copolymer (“N1525” melting point 93 ° C., glass transition temperature 26 ° C., manufactured by Mitsui DuPont Polychemicals). Except for the above, a foamed laminated sheet was obtained in the same manner as in Example 1.

Example 4
Of the surface protective layer of Example 3, a foamed laminated sheet was obtained in the same manner as in Example 3 except that the lower layer was formed with a thickness of 4 μm and the upper layer was formed with a thickness of 8 μm.

Comparative Example 1
A foamed laminated sheet was obtained in the same manner as in Example 1 except that the surface protective layer (upper layer and lower layer) was composed of polyethylene.

  Specifically, using a T-die extruder capable of forming two types and two layers, the thickness of the surface protective layer B (upper layer) and the surface protective layer A (lower layer) is 8 μm and 4 μm in order. And then laminated on the non-foamed resin layer A.

  Extrusion cylinder temperature: 250 ° C., T-die temperature was 250 ° C.

  As the material of the surface protective layer A, a modified polyethylene (Mitsubishi Chemical “Modic M605” melting point 111 ° C., glass transition temperature −20 ° C.) is used, and as the material of the surface protective layer B, polyethylene (manufactured by Nippon Polyethylene “ LC720 ”melting point 110 ° C., glass transition temperature −120 ° C.).

  Except for the above, the procedure was the same as in Example 1.

Comparative Example 2
A foamed laminated sheet was obtained in the same manner as in Example 1 except that, of the surface protective layer of Example 1, only the lower layer was formed with a thickness of 10 μm without providing the upper layer.

Comparative Example 3
A foamed laminated sheet was obtained in the same manner as in Example 1 except that, of the surface protective layer of Example 1, only the upper layer was formed with a thickness of 12 μm without providing a lower layer.

Except for the above, the procedure was the same as in Example 1.
≪Evaluation of foam laminated sheet≫
About the foaming lamination sheet produced by the Example and the comparative example, the embossing moldability evaluation, the low temperature curl load evaluation, the protruding corner test, and the contamination test were done.

  The evaluation (test) method and evaluation criteria were as follows.

Emboss moldability evaluation Measure the surface shape of the embossed uneven pattern of each foamed laminated sheet using Keyence's one-shot shape measuring instrument "VR-3000" Depth reach rate (%) was specified with the pattern shaped as 100%. The evaluation criteria were as follows.
○: Reached to a depth of 65% or more ×: Reached a depth of less than 65%
Low-temperature curl load evaluation Samples of each foamed laminated sheet (length 7.5 cm, width 7.5 cm) were wound around a paper tube (φ = 1.5 inches) and allowed to stand for at least 40 ° C. for 24 hours to curl. Next, after being immersed in ice water (0 ° C.) for 30 minutes, a PET plate was placed on the foamed laminated sheet, and a weight was further placed thereon, and the load (g) at which there was no curl and the entire surface was measured. The evaluation criteria were as follows.
○: 25.0 g or less and the handling of the foamed laminated sheet is very good Δ: Exceeding 25.0 g and the handling of the foamed laminated sheet is good (allowable range)
X: Exceeding 30.0 g and handling of the foam laminated sheet is difficult
Out corner test (scratch resistance evaluation)
Paste each foamed laminated sheet sample (5 cm long, 10 cm wide) on a base shaped like a square column lying down horizontally, rub the gold with a Gakushin abrasion machine (load 500 g), and see the backing paper by scratching The number of round trips was measured.

  As is clear from the results in Table 1, the foamed laminated sheets of Examples 1 to 4 having a surface protective layer having a multilayer structure and having the surface protective layer A and the surface protective layer B containing the resin component specified in the present invention are as follows. By comparing with the foamed laminated sheets of Comparative Examples 1 to 3, it can be seen that the scratch resistance and embossability are excellent, and curling in a low temperature environment is suppressed, and the winter workability is excellent.

1. Base material (fibrous sheet)
2. Non-foamed resin layer B
3. Foaming agent-containing resin layer 3 ′. 3. Foamed resin layer Non-foamed resin layer A
5. Pattern layer 6 Primer layer 7. Surface protective layer 7-A. Surface protective layer A
7-B. Surface protective layer B
8). Embossed uneven pattern

Claims (7)

A laminated sheet having at least a foaming agent-containing resin layer and a surface protective layer on a substrate,
(1) The surface protective layer has a multilayer structure, and has a surface protective layer A and a surface protective layer B from the side close to the substrate.
(2) The surface protective layer A contains a resin having a glass transition temperature of 0 ° C. or lower, and the surface protective layer B contains an ethylene- (meth) acrylic acid copolymer.
A laminated sheet characterized by that.   The laminated sheet according to claim 1, wherein the resin having a glass transition temperature of 0 ° C or lower has a melting point of 60 to 100 ° C.   The laminated sheet according to claim 1 or 2, wherein the ethylene- (meth) acrylic acid copolymer has a melting point of 60 to 100 ° C.   The ratio of the thickness of the said surface protective layer A and the said surface protective layer B is the surface protective layer A: the surface protective layer B = 0.5-5: 1 in any one of Claims 1-3. Laminated sheet.   The laminated sheet according to any one of claims 1 to 4, wherein the foaming agent-containing resin layer has a non-foamed resin layer on one side or both sides. A foam laminated sheet having at least a foamed resin layer and a surface protective layer on a substrate,
(1) The surface protective layer has a multilayer structure, and has a surface protective layer A and a surface protective layer B from the side close to the substrate.
(2) The surface protective layer A contains a resin having a glass transition temperature of 0 ° C. or lower, and the surface protective layer B contains an ethylene- (meth) acrylic acid copolymer.
A foamed laminated sheet characterized by that.   The foaming laminated sheet of Claim 6 which has an embossing uneven | corrugated pattern on the front surface.