JP7003808B2 - Laminated sheet and foam laminated sheet - Google Patents

Description

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

The foamed laminated sheet has a foamed resin layer and is useful as a foamed wallpaper, various decorative materials, and the like. Further, the laminated sheet means a state before foaming (so-called unfoamed raw fabric) of the foamed laminated sheet.

Conventionally, a foamed laminated sheet in which at least a foamed resin layer and a surface protective layer are provided on a base material is known, and is used as a 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 coated by a coating method such as a comma coat, or a calendar method in which a resin composition is stretched into a sheet and laminated. , It is known that molding is performed by an extrusion film forming using an extruder such as a T-die.

For example, Patent Document 1 states, "A method for manufacturing a laminated sheet in which at least a foaming agent-containing resin layer and a surface protective layer are sequentially formed on a base material.
(1) The surface protective layer is composed of a single layer or a plurality of 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 1.
(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, which comprises a step 3 of cross-linking 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 and electron beam. By irradiating the resin component of the surface protective layer with cross-linking, a laminated sheet having good production stability and excellent stain resistance and scratch resistance is obtained (paragraph [0014]).

When the surface protective layer is a multi-layer, a layer containing a resin other than polyethylene and / or an ethylene copolymer may be combined as a resin layer other than the layer containing polyethylene and / or an ethylene copolymer. It is described ([0059] paragraph). The laminated sheet becomes a foamed laminated sheet by foaming a foaming agent-containing resin layer, and is used for applications such as foamed wallpaper and decorative materials.

Japanese Unexamined Patent Publication No. 2012-213939 Japanese Unexamined Patent Publication No. 2012-052413 Japanese Unexamined Patent Publication No. 2001-058375

However, the foamed laminated sheet described in Patent Document 1 has a lower embossing type property and is prone to curl in a low temperature environment and has poor winter workability as compared with a foamed laminated sheet having no surface protective layer. Is a problem.

In this regard, Patent Document 2 describes that a foaming resin layer mainly composed of a foaming agent and an olefin resin or an acrylic resin, a pattern layer, and a heat-melted non-halogen-based thermoplastic resin are extruded and coated on a base material layer. In order to improve the workability of the wall mounting sheet in which the surface protective layer formed by the construction method is provided in order, the flexural 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 it, curl suppression in a low temperature environment is not mentioned, and there is still room for improvement in embossing type by simply adjusting the flexural modulus.

Further, in Patent Document 3, a foaming 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 mounting sheet, it has been proposed that the surface protective layer is made of a non-halogen thermoplastic resin and an amorphous resin, but the amorphous resin has chemical resistance and resistance. There is still room for improvement in scratch resistance, and no particular mention is made of embossing-type properties.

The present invention has been completed in view of the above-mentioned problems of the prior art, 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 embossing type. At the same time, it is an object of the present invention to provide a foamed laminated sheet in which curling is suppressed in a low temperature environment and has excellent workability in winter, and a laminated sheet useful for producing the foamed laminated sheet.

As a result of diligent research to achieve the above-mentioned problems, the present inventor has achieved the above object by having a surface protective layer having a multi-layer structure and having a surface protective layer A and a surface protective layer B containing a specific resin component. We have found that this can be achieved and have completed the present invention.

That is, the present invention relates to the following laminated sheet and foam laminated sheet.
1. 1. A laminated sheet having at least a foaming agent-containing resin layer and a surface protective layer on a base material.
(1) The surface protective layer has a multi-layer structure, and has the surface protective layer A and the surface protective layer B from the side closer to the base material.
(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. 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. 3. Item 2. 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 to the surface protective layer B is described in any one of Items 1 to 3 above, wherein the surface protective layer A: the surface protective layer B = 0.5 to 5: 1. Laminated sheet.
5. Item 2. The laminated sheet according to any one of Items 1 to 4, wherein the foaming agent-containing resin layer has a non-foaming resin layer on one side or both sides.
6. A foamed laminated sheet having at least a foamed resin layer and a surface protective layer on a base material.
(1) The surface protective layer has a multi-layer structure, and has the surface protective layer A and the surface protective layer B from the side closer to the base material.
(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 6. The foam laminated sheet according to Item 6, which has an embossed uneven pattern on the front surface.

In the laminated sheet of the present invention, the surface protective layer has a multi-layer structure, and by having the surface protective layer A and the surface protective layer B containing a specific resin component, the foaming agent-containing resin layer is foamed to form a foamed laminated sheet. When used as an oleoresin, it has excellent scratch resistance and embossing property, and curl is suppressed in a low temperature environment, so that it is excellent in winter workability. The foamed laminated sheet of the present invention can be widely used as various decorative materials such as foamed wallpaper.

It is sectional drawing which shows an example of the layer structure of the laminated sheet of this invention. It is sectional drawing which shows an example of the layer structure of the foam laminated 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, and (1) the surface protective layer has a multi-layer structure, and the surface protective layer is formed from the side close to the substrate. It has A and a surface protection 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.

In the laminated sheet of the present invention having the above characteristics, the surface protective layer has a multi-layer structure, and by having the surface protective layer A and the surface protective layer B containing a specific resin component, the foaming agent-containing resin layer is foamed. When used as a foamed laminated sheet, it has excellent scratch resistance and embossing property, and curl is suppressed in a low temperature environment, so that it is excellent in winter workability. The foamed laminated sheet of the present invention can be widely used as various decorative materials such as foamed wallpaper.

Hereinafter, each layer constituting the laminated sheet will be described. In the present specification, the direction in which the foaming agent-containing resin layer is laminated when viewed from the base material is referred to as "upper" or "front surface", and the foaming agent-containing resin layer is laminated when viewed from the base material. The side opposite to the direction in which the sheet is used is referred to as "bottom" or "back surface" (the same applies to the foamed laminated sheet described later).

Base material (fiber sheet)
The base material is not limited, and a known fibrous sheet (backing paper) or the like can be used.

Specifically, general paper for wallpaper (pulp-based sheet size-treated with a known sizing agent); flame-retardant paper (pulp-based sheet treated with a flame-retardant agent such as guanidine sulfamate or guadinin phosphate). ); Inorganic paper containing inorganic additives such as aluminum hydroxide and magnesium hydroxide; High-quality paper; Thin paper; Fiber-blended paper (pulp and synthetic fiber mixed and paper-made) and the like. The fibrous sheet used in the present invention also includes those that are classified as non-woven fabrics.

The basis weight of the base material is not limited, but is preferably about 50 to 300 g / m ² , and more preferably about 50 to 130 g / m ² .

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 resin, olefin resin, etc., which have been conventionally used for foamed laminated sheets, can be widely adopted, but 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-based resin is preferable to a vinyl chloride resin, and specifically, an ethylene-based resin is preferably contained.

Examples of the ethylene-based resin include not only polyethylene (PE) but also an ethylene copolymer having ethylene and a component other than ethylene as a monomer (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 membrane formation in terms of melting point and MVR (melt volume flow rate). Examples of the ethylene copolymer include an ethylene-vinyl acetate copolymer (EVA), an ethylene-methylmethacrylate copolymer (EMMA), an ethylene-acrylic acid copolymer (EAA), and an ethylene-ethylacrylate copolymer (EAA). EEA), ethylene-methyl acrylate copolymer (EMA), ethylene-methacrylic acid copolymer (EMAA), ethylene-α-olefin copolymer and the like can be mentioned. 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, and when at least one of EVA, EMMA and EMAA is used in combination with one or more of other resins, EVA, EMMA and one or more thereof are used in combination. The content of at least one of EMAA is preferably 70% by mass or more, more preferably 80% by mass or more.

The content of the monomer other than ethylene of the ethylene copolymer is preferably 5 to 25% by mass, more preferably 9 to 20% by mass. By adopting such a copolymerization ratio, the extruded film-forming property is further enhanced. As a specific example, the ethylene-vinyl acetate copolymer preferably has a copolymerization ratio (VA amount) of 9 to 25% by mass, more preferably 9 to 20% by mass. The ethylene-methylmethacrylate copolymer preferably has a copolymerization ratio (MMA amount) of 5 to 25% by mass, more preferably 5 to 15% by mass. The ethylene-methacrylic acid copolymer preferably has an acrylic acid copolymerization ratio (MAA amount) of 2 to 15% by mass, more preferably 5 to 11% by mass.

The resin component contained in the foaming agent-containing resin layer preferably has an MVR of 10 to 40 cm ^3/10 min as measured under the conditions of 130 ° C. and a load of 21.18 N described in the JIS K7210 B method. If the MVR is too large, the resin may be too soft and the scratch resistance of the formed resin layer may be insufficient. In addition, MVR in this specification is a value measured under the said condition.

Examples of the pyrolytic foaming agent include azo-based materials such as azodicarbonamide (ADCA) and azobisformamide; hydrazide-based products such as oxybenzenesulfonyl hydrazide (OBSH) and paratoluenesulfonyl hydrazide. The content of the pyrolysis type foaming agent can be appropriately set according to the type of foaming agent, the foaming ratio, and the like. From the viewpoint of the foaming ratio, it is 1.5 times or more, preferably about 3 to 7 times, and the thermal decomposition type 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 pyrolysis 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. The content of these foaming aids is preferably about 0.3 to 10 parts by mass, more preferably about 1 to 5 parts by mass with respect to 100 parts by mass of the resin component.

When these foaming aids are used in combination with EMAA and ADCA, there is a problem that the effect as a foaming aid is impaired by the reaction between the carboxyl base of EMAA and the metallic foaming aid during foaming. be. Therefore, 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 to 1 part by mass of the carboxylic acid hydrazide compound with respect to 1 part by mass of ADCA.

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

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

Regarding pigments, as inorganic pigments, for example, titanium oxide, zinc flower, carbon black, black iron oxide, yellow iron oxide, chrome yellow, molybdate orange, cadmium yellow, nickel titanium yellow, chrome titanium yellow, iron oxide (valve handle). ), Cadmium red, ultramarine, dark blue, cobalt blue, chromium oxide, cobalt green, aluminum powder, bronze powder, mica titanium, zinc sulfide and the like. Further, as organic pigments, for example, aniline black, perylene black, azo type (azolake, insoluble azo, fused azo), polycyclic type (isoindoline, isoindoline, quinophthalocyanine, perinone, flavantron, anthrapyrimidine, anthraquinone, quinacridone). , Perylene, diketopyrrolopyrrole, dibrom anzantron, dioxazine, thioindigo, phthalocyanine, indantron, halogenated phthalocyanine) and the like. These pigments can be used alone or in admixture of two or more. The content of the pigment is preferably about 1 to 50 parts by mass, more preferably about 2 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 crosslinked with a resin. As a method for cross-linking the resin, there are a method using a peroxide and a method for cross-linking by irradiating an electron beam. The method of irradiating the foaming agent-containing resin layer with an electron beam and the method of foaming may be carried out according to the method described in the production method described later.

In the present invention, it is preferable to set the MVR of the resin composition (compound) forming the foaming agent-containing resin layer at 130 ° C. to 16 cm ^3/10 minutes or more. As a result, 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 as long as the film formation is possible, but it is preferably 25 cm ^3/10 minutes or less. By setting the MVR to 16 to 25 cm for ^3/10 minutes, the foaming agent-containing resin layer can be suitably formed by extrusion film formation, and the foaming characteristics can be further improved.

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-foaming resin layer on one side or both sides thereof.

For example, a non-foaming resin layer B (adhesive resin layer) may be provided on the back surface of the foaming agent-containing resin layer (the surface on which the fibrous sheet is laminated) for the purpose of improving the adhesive force 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. Known or commercially available EVA can be used. In particular, a vinyl acetate component (VA component) of 10 to 46% by mass is preferable, and a vinyl acetate component (VA component) of 15 to 41% by mass is more preferable.

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.

A non-foaming 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 and improving the scratch resistance of the foaming resin layer.

Examples of the resin component of the non-foaming resin layer A include polyolefin resins, methacrylic resins, thermoplastic polyester resins, polyvinyl alcohol resins, fluororesins and the like, and among them, polyolefin resins are preferable.

Examples of the polyolefin-based resin include polyethylene (low-density polyethylene (LDPE) or high-density polyethylene (HDPE)), a single resin such as polypropylene, polybutene, polybutadiene, and polyisoprene, and ethylene and α-olefin having 4 or more carbon atoms. Polymers (linear low density polyethylene (LLDPE)), ethylene-acrylic acid copolymers, ethylene-methyl acrylate copolymers, ethylene-ethyl acrylate copolymers, ethylene-methacrylic acid copolymers and other ethylene ( Meta) At least one of acrylic acid-based copolymers, ethylene-vinyl acetate copolymers (EVA), ethylene-vinyl acetate copolymers kendies, ethylene-vinyl alcohol copolymers, ionomers and the like can be mentioned.

In the present invention, particularly when a vinyl chloride resin is used as the resin in the foaming agent-containing resin layer, the non-foaming resin layer A (particularly the ethylene-vinyl alcohol copolymer layer) is used in order to obtain the durability of the laminated sheet. It is preferable to form it. In addition, "(meth) acrylic acid" means acrylic acid or methacrylic acid, and the same applies to the portion described as other (meta).

The thickness of the non-foamed resin layer A is not limited, but is preferably about 2 to 50 μm, more preferably about 5 to 20 μm.

In the present invention, it is preferable that the non-foaming resin layer B, the foaming agent-containing resin layer, and the non-foaming resin layer A are formed in this order from the viewpoint of manufacturing described later.

Picture pattern layer In the laminated sheet of the present invention, a picture pattern layer may be formed on a resin layer (foaming agent-containing resin layer, non-foaming resin layer A, etc.) or a primer layer described later, if necessary.

The pattern pattern layer imparts design to the laminated sheet and the foamed laminated sheet. Examples of the pattern include wood grain pattern, stone grain pattern, sand grain pattern, tiled pattern, brick pile pattern, cloth grain pattern, leather squeezing pattern, geometric figure, character, symbol, abstract pattern, flower pattern and the like. It can be selected according to the purpose.

The pattern pattern layer can be formed, for example, by printing a pattern. Examples of the printing method include gravure printing, flexographic printing, silk screen printing, and offset printing. 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 such as that used in the 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. Examples thereof include based resins, melamine based resins, fluororesins, silicone resins, fibrous derivatives, rubber resins and the like.

Examples of the solvent (or dispersion medium) include petroleum-based organic solvents such as hexane, heptane, octane, toluene, xylene, ethylbenzene, cyclohexane, and methylcyclohexane; ethyl acetate, butyl acetate, -2-methoxyethyl acetate, and -2 acetate. -Ether-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 and propylene glycol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone. Examples thereof include ether-based organic solvents such as diethyl ether, dioxane, and tetrahydrofuran, and chlorine-based organic solvents such as dichloromethane, carbon tetrachloride, trichloroethylene, and tetrachloroethylene; water and the like. These solvents (or dispersion media) can be used alone or in the form of a mixture.

The thickness of the pattern layer varies depending on the type of pattern, but is generally preferably about 0.1 to 10 μm.

Primer layer A primer layer may be formed on the resin layer (foaming agent-containing resin layer, non-foaming 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, and in particular, acrylic, chlorinated polypropylene and the like can be used. Is desirable.

Examples of acrylics include methyl poly (meth) acrylic acid, ethyl poly (meth) acrylic acid, propyl poly (meth) acrylic acid, butyl poly (meth) acrylic acid, and methyl (meth) acrylic acid- (meth) acrylic acid. (Meta) such as butyl copolymer, ethyl (meth) acrylate- (meth) butyl acrylate copolymer, ethylene- (meth) methyl acrylate copolymer, styrene- (meth) methyl acrylate copolymer, etc. Examples thereof include an acrylic resin containing an acrylic acid ester alone or made of a copolymer.

Polyurethane is a composition containing a polyol (polyhydric alcohol) as a main component and an isocyanate as a cross-linking agent (curing agent).

As the polyol, those 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.

Further, 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, and 4,4-diphenylmethane diisocyanate, or aliphatic (or fat) such as hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Cyclic) isocyanate is 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 laminated sheet of the present invention has a surface protective layer on a base material together with a foaming agent-containing resin layer.

The surface protective layer is provided on the surface of a resin layer (foaming agent-containing resin layer, non-foaming resin layer A, etc.), a pattern layer, or a primer layer. In the present invention, the surface protective layer has a multi-layer structure and is used as a base material. By having a specific surface protective layer A and surface protective layer B from the near side, the final product, the foamed laminated sheet, has excellent scratch resistance and embossing property, and curl in a low temperature environment is suppressed, so that it is constructed in winter. The effect of being excellent in sex can be obtained. Further, the surface protective layer can also be provided with the effects of gloss adjustment and / or protection of the pattern layer.

FIG. 1 shows an example of a suitable layer structure of the laminated sheet of the present invention. In FIG. 1, a non-foaming resin layer B2, a foaming agent-containing resin layer 3, a non-foaming resin layer A4, a pattern layer 5 and a primer layer 6 are laminated in this order on the base material 1, and surface protection is performed on the primer layer 6. Layer 7 (surface protective layer 7-A and surface protective layer 7-B from the substrate side) is laminated.

The surface protective layer A contains a resin having a glass transition temperature of 0 ° C. or lower. As a result, the surface protective layer A has a role of imparting embossing-type property to the foamed laminated sheet and winter workability based on suppression of curl in a low temperature environment.

The resin having a glass transition temperature of 0 ° C. or lower is not limited, but is a polyethylene, an ethylene-vinyl acetate copolymer, an ethylene-vinyl acetate- (meth) acrylic acid copolymer (a ternary copolymer, and is a ternary copolymer. Hereinafter, at least one kind such as "ternary copolymer") and the like can be mentioned. By containing a resin having a glass transition temperature of 0 ° C. or lower, the surface protective layer A imparts embossing-type property to the foamed laminated sheet and winter workability based on suppression of curl in a low temperature environment. There is a role. As the resin having a glass transition temperature of 0 ° C. or lower, a ternary copolymer is preferable among the resins listed above, and an ethylene-vinyl acetate-methacrylic acid copolymer is particularly preferable. The ternary copolymer can be appropriately selected from commercially available products and used.

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

The glass transition temperature in the present specification is a value determined by measuring dynamic viscoelasticity. Further, the melting point in the present specification is a value measured by DSC.

The resin component of the surface protective layer A may be composed only of a resin having a glass transition temperature of 0 ° C. or lower, but other resin components (that is, a resin having a glass transition temperature exceeding 0 ° C.) may be used in combination. In this case, the content of the resin having a glass transition temperature of 0 ° C. or lower in 100% by mass of the resin component is preferably 80% by mass or more so that the resin having a glass transition temperature of 0 ° C. or lower is the main component. , 90% by 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 a weather resistant agent, an antistatic agent, and an antibacterial agent.

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

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

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

Further, the surface protective layer B may contain additives such as a weather resistant agent, an antistatic agent, and an antibacterial agent.

In the present invention, the surface protective layer having a plurality of configurations is arranged in the order of the surface protective layer A and the surface protective layer B from the side closer to the base material. In order to effectively obtain the scratch resistance, embossing type property, and winter workability based on the suppression of curling in a low temperature environment, the ratio of the thickness of the surface protective layer A and the surface protective layer B should be Although not limited, surface protective layer A: surface protective layer B = 0.5 to 5: 1 is preferable, and 1 to 3: 1 is more preferable.

The surface protective layer having a plurality of configurations may be composed of the 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. As the ionizing radiation curable resin, one that is radically polymerized (cured) by electron beam irradiation is preferable.

Further, when the purpose of gloss adjustment is also given 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-mentioned overcoat layer.

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

An embossed pattern may be provided on the front surface of the embossed laminated sheet or the foamed laminated sheet. In this case, embossing may be performed from above the outermost surface layer (the side opposite to the fibrous sheet). The embossing can be performed by a 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 heating and softening the front surface of the surface protective layer.

Examples of the embossed pattern include a wood grain conduit groove, a stone board surface unevenness, a cloth surface texture, a satin finish, a grain, a hairline, a geometric pattern, a perforated groove, and a contour pattern.
≪Foam laminated sheet≫
The foamed laminated sheet of the present invention is 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 protection layer on the base material.
(1) The surface protective layer has a multi-layer structure, and has the surface protective layer A and the surface protective layer B from the side closer to the base material.
(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.

FIG. 2 shows an example of a suitable layer structure of the foamed laminated sheet of the present invention. In FIG. 2, a non-foaming resin layer B2, a foaming resin layer 3', a non-foaming resin layer A4, a pattern layer 5 and a primer layer 6 are laminated in this order on the base material 1, and a surface protective layer is formed on the primer layer 6. 7 (surface protective layer 7-A and surface protective layer 7-B from the base material side) are laminated. Further, an embossed uneven pattern 8 is provided on the outermost surface side of the foamed laminated sheet.
≪Manufacturing method of laminated sheet and foam laminated sheet≫
Examples of the manufacturing method of the laminated sheet include a manufacturing method in which at least the foaming agent-containing resin layer and the surface protective layer are laminated on a base material.

Further, as a method for manufacturing a foamed laminated sheet, in the method for manufacturing a laminated sheet, after laminating the foaming agent-containing resin layer and the surface protective layer, the foaming agent-containing resin layer is foamed by heat treatment to form a foamed resin layer. The manufacturing method to be carried out can be mentioned.

When the foaming agent-containing resin layer has a non-foaming resin layer on one side or both sides thereof, the non-foaming resin layer B and / or the non-foaming resin layer A may be formed by extrusion film formation, or each film may be formed. Although it may be formed by thermal laminating, simultaneous extrusion film formation by a T-die extruder is preferable. For example, when the non-foaming resin layers are provided on both sides, a multi-manifold type T-die capable of simultaneously forming three layers by simultaneously extruding the molten resin corresponding to the three layers can be used.

When the resin composition forming the foaming agent-containing resin layer contains an inorganic filler and the foaming agent-containing resin layer is formed by extrusion film formation, it is inorganic at the extrusion port (so-called die lip) of the extruder. Residues of the filler (so-called rheumatism) are likely to be generated, and these are likely to become foreign substances on the surface of the foaming agent-containing resin layer. Therefore, when the resin composition forming the foaming agent-containing resin layer contains an inorganic filler, it is preferable to simultaneously extrude three layers to form a film so that the non-foaming resin layer does not contain an inorganic substance. That is, by simultaneously extruding and forming a film by sandwiching the foaming agent-containing resin layer with the non-foaming resin layer containing no inorganic substance, it is possible to suppress the occurrence of the rheumatism.

After forming the foaming agent-containing resin layer, electron beam irradiation may be performed. This makes it possible to crosslink the resin component 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, more preferably about 10 to 50 kGy. As the electron beam source, a known electron beam irradiation device can be used.

A pattern layer and a primer layer are formed on the foaming agent-containing resin layer in an arbitrary order, and then a surface protective layer is formed to form a laminated sheet, which is then heat-treated to form a foaming agent-containing resin layer. A foamed laminated sheet can be obtained by forming a foamed resin layer. Taking the laminated sheet shown in FIG. 1 as an example, each layer can be laminated by combining coatings such as printing and coating, extruded film forming 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 thermal decomposition type foaming agent, and the heating temperature is preferably about 210 to 240 ° C., and the heating time is preferably about 25 to 80 seconds. In addition, when embossing a pattern is applied, it is carried out by a known means such as pressing an embossed plate.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. However, the present invention is not limited to the examples.

Example 1
≪Manufacturing of foam laminated sheet≫
Using a T-die extruder capable of forming 3 types and 3 layers, the resin layer has a thickness of 5 μm, 50 μm, and 5 μm in the order of non-foaming resin A, foaming agent-containing resin layer, and non-foaming resin B. Was extruded to form a film. A film was formed at an extrusion cylinder temperature of 120 ° C. and a T-die temperature of 120 ° C.

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

The materials for each layer are 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 ("Typake CR-63" manufactured by Ishihara Sangyo) , Calcium carbonate ("Whiten H" manufactured by Toyo Fine Chemicals) 20 parts by mass, pyrolytic foaming agent ("Vinihole AC # 3" manufactured by Eiwa Kasei Kogyo) 5 parts by mass, foaming aid ("ADHS" manufactured by Otsuka Chemical Co., Ltd.) 4 A mixture of parts by mass,
Non-effervescent resin A: Ethylene-methacrylic acid copolymer (Mitsui / DuPont Polychemical "N1560")
Non-effervescent resin B: Ethylene-vinyl acetate copolymer (“EV150” manufactured by Mitsui / DuPont Polychemical).

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

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

As the material of the surface protective layer A, an ethylene-vinyl acetate-methacrylic acid copolymer (manufactured by Mitsui / Dupont Polychemical, ternary copolymer "N035C", melting point 86 ° C., glass transition temperature -10 ° C.) is used. As the material of the surface protective layer B, an ethylene-methacrylic acid copolymer (manufactured by 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 onto the surface protective layer B, and an electron beam (190 kV, 50 kGy) was irradiated from above the electron beam curable urethane acrylate resin 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 to press the embossed plate to obtain a desired foamed laminate having an uneven pattern on the surface. I got a sheet.

Example 2
Among the surface protective layers 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 layers of Example 1, the material of the surface protective layer B (upper layer) was composed of an ethylene-methacrylic acid copolymer (“N1525” manufactured by Mitsui and DuPont Polychemical, melting point 93 ° C., glass transition temperature 26 ° C.). A foamed laminated sheet was obtained in the same manner as in Example 1 except for the above.

Example 4
Among the surface protective layers 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 made of polyethylene.

Specifically, using a T-die extruder capable of forming two types of two layers, the thickness of the surface protective layer B (upper layer) and the surface protective layer A (lower layer) are set to 8 μm and 4 μm in this order. The film was extruded and laminated on the non-foaming resin layer A.

A film was formed at an extrusion cylinder temperature of 250 ° C. and a T-die temperature of 250 ° C.

As the material of the surface protective layer A, a polyethylene modified product (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.) was used.

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

Comparative Example 2
A foamed laminated sheet was obtained in the same manner as in Example 1 except that only the lower layer of the surface protective layer of Example 1 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 only the upper layer of the surface protective layer of Example 1 was formed with a thickness of 12 μm without providing the lower layer.

Except for the above, the same as in Example 1 was applied.
≪Evaluation of foam laminated sheet≫
The foamed laminated sheets produced in Examples and Comparative Examples were subjected to embossing type evaluation, low temperature curl load evaluation, protrusion corner test and contamination test.

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

Evaluation of embossed shapeability The surface shape of the embossed uneven pattern of each foam laminated sheet is measured using the one-shot shape measuring device "VR-3000" manufactured by KEYENCE, and the height integration of a specific part is applied to the unevenness of the embossed plate on silicon. The pattern was set as 100%, and the depth arrival rate (%) was specified. The evaluation criteria are as follows.
◯: Reached to a depth of 65% or more ×: Reached to a depth of less than 65%
Low temperature curl load evaluation
A sample of each foam laminated sheet (length 7.5 cm, width 7.5 cm) was wrapped around a paper tube (φ = 1.5 inch) and left at 40 ° C. for 24 hours or more to curl it. Then, after immersing in ice water (0 ° C.) for 30 minutes, a PET plate was placed on the foamed laminated sheet, and a weight was placed on the foam laminated sheet, and the load (g) at which the whole was flat without curling was measured. The evaluation criteria are as follows.
◯: 25.0 g or less and the handling of the foamed laminated sheet is very good Δ: 25.0 g or more and 30 g or less and the handling of the foamed laminated sheet is good (allowable range)
X: It is difficult to handle the foamed laminated sheet because it exceeds 30.0 g.
Outer corner test (scratch resistance evaluation)
A sample of each foam laminated sheet (length 5 cm, width 10 cm) is pasted on a base shaped like a side-by-side prism, rub a gold cloth with a Gakushin wear machine (load 500 g), and the backing paper can be seen by scratches. The number of round trips to was measured.

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

1. 1. Base material (fiber sheet)
2. 2. Non-foaming resin layer B
3. 3. Foaming agent-containing resin layer 3'. Foamed resin layer 4. Non-foaming resin layer A
5. Pattern pattern layer 6. Primer layer 7. Surface protective layer 7-A. Surface protection 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 base material.
(1) The surface protective layer has a multi-layer structure, and has the surface protective layer A and the surface protective layer B from the side closer to the base material.
(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 surface protective layer A to the surface protective layer B is according to any one of claims 1 to 3, wherein the surface protective layer A: the surface protective layer B = 0.5 to 5: 1. Laminated sheet. The laminated sheet according to any one of claims 1 to 4, wherein the foaming agent-containing resin layer has a non-foaming resin layer on one side or both sides. A foamed laminated sheet having at least a foamed resin layer and a surface protective layer on a base material.
(1) The surface protective layer has a multi-layer structure, and has the surface protective layer A and the surface protective layer B from the side closer to the base material.
(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 foamed laminated sheet according to claim 6, which has an embossed uneven pattern on the front surface.

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