JP6492408B2 - Laminated sheet and foam laminated sheet - Google Patents

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. The laminated sheet means a state before foaming of the foamed laminated sheet (so-called unfoamed raw fabric) or a sheet useful as various decorative materials in a state where no foamed resin layer is provided.

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

  As a method of forming the foaming agent-containing resin layer, among the above, the extrusion film formation is excellent from the viewpoint of production efficiency, and the foaming agent-containing resin layer is sandwiched between the non-foaming resin layers from the viewpoint of improving the surface strength. A method of forming a three-layer coextrusion film in a state is known. In addition, when three-layer coextrusion film formation is performed, a layer (non-foamed resin layer A) laminated on the surface opposite to the base material of the foaming agent-containing resin layer is formed from the viewpoint of further improving the surface strength. It is known to use a (meth) acrylic acid copolymer (for example, refer to Patent Document 1).

  However, when the foaming resin layer is formed by foaming the foaming agent-containing resin layer, a resin having a low polarity, such as vinyl acetate, is added to the foaming agent-containing resin layer in order to provide the followability necessary for forming bubbles. When an ethylene-vinyl acetate copolymer having a relatively small content is used, the foaming agent-containing resin layer and a non-foamed resin layer A containing an ethylene- (meth) acrylic acid copolymer that is a polar resin There is a problem that the adhesion is lowered. For this reason, when the foaming agent-containing resin layer is foamed to obtain a foamed resin layer, bubbles are generated between the foamed resin layer and the non-foamed resin layer A, and the non-foamed resin layer A partially floats. There is a problem of becoming a state.

  Moreover, when embossing is performed on the foamed laminated sheet formed as described above, the portion where the non-foamed resin layer A is lifted is stretched, and the surface of the foamed laminated sheet reflects light in a scaly manner. There is a problem that the designability is lowered. Further, the portion where the non-foamed resin layer A is floated has a problem that the non-foamed resin layer A easily falls off, resulting in a defective portion.

  Further, the portion where the non-foamed resin layer A is floated is liable to be damaged when rubbed, resulting in a problem of poor scratch resistance.

  Further, when an ethylene- (meth) acrylic acid copolymer is used for the foaming agent-containing resin layer in order to improve the adhesion between the foaming agent-containing resin layer and the non-foaming resin layer A, the foaming agent-containing resin layer is hard. There is a problem that it is difficult to form bubbles.

  Therefore, by having excellent adhesion between the foaming agent-containing resin layer of the laminated sheet and the non-foamed resin layer A, scaly peeling between the foamed resin layer of the foamed laminated sheet and the non-foamed resin layer A is suppressed. Development of new laminated sheets and foamed laminated sheets that are excellent in scratch resistance is also demanded.

JP 2007-55229 A

  An object of the present invention is to provide a laminated sheet and a foamed laminated sheet, in which scale-like peeling between the foamed resin layer of the foamed laminated sheet and the non-foamed resin layer A is suppressed and excellent in scratch resistance.

  As a result of intensive studies to achieve the above object, the present inventor has obtained a non-foamed resin layer in a laminated sheet in which at least a foaming agent-containing resin layer and a non-foamed resin layer A are laminated in this order on a substrate. A contains an ethylene- (meth) acrylic acid copolymer, and the foaming agent-containing resin layer has an ethylene-vinyl acetate copolymer having a vinyl acetate content (VA value) of 20% by mass or less; It has been found that the above object can be achieved by employing a constitution containing at least one selected from a resin and a specific wax, and the present invention has been completed.

That is, the present invention relates to the following laminated sheet and foamed laminated sheet.
1. A laminated sheet in which at least a foaming agent-containing resin layer and a non-foamed resin layer A are laminated in this order on a substrate,
(1) The non-foamed resin layer A contains an ethylene- (meth) acrylic acid copolymer,
(2) The foaming agent-containing resin layer comprises an ethylene-vinyl acetate copolymer having a vinyl acetate content (VA value) of 20% by mass or less, the following component (a) and / or component (b):
(A) a resin having a carboxyl group and / or a carboxylic anhydride group;
(B) a wax having a carboxyl group and / or a carboxylic anhydride group;
Containing,
A laminated sheet characterized by that.
2. The said item whose sum total of content of the said (a) component in the said foaming agent containing resin layer and the said (b) component is 2-20 mass parts with respect to 100 mass parts of said ethylene-vinyl acetate copolymers. The laminated sheet according to 1.
3. The component (a) is selected from a copolymer containing an olefin, (meth) acrylic acid and / or maleic anhydride as monomer components, and a modified polyolefin resin with (meth) acrylic acid and / or maleic anhydride. Item 3. The laminated sheet according to Item 1 or 2, which is at least one kind.
4). Item 4. The laminated sheet according to any one of Items 1 to 3, wherein the component (b) is a modified wax with (meth) acrylic acid and / or maleic anhydride.
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 B on a surface opposite to a surface on which the non-foamed resin layer A is formed.
6). The foaming lamination sheet obtained by foaming the said foaming agent containing resin layer of the lamination sheet in any one of said items 1-5.
7). Item 7. The foamed laminated sheet according to Item 6, wherein embossing is performed on the outermost surface layer.

  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 is a laminated sheet in which at least a foaming agent-containing resin layer and a non-foamed resin layer A are laminated in this order on a substrate. (1) The non-foamed resin layer A is an ethylene- (2) The foaming agent-containing resin layer contains an ethylene-vinyl acetate copolymer having a vinyl acetate content (VA value) of 20% by mass or less, and the following (a): Component and / or component (b):
(A) a resin having a carboxyl group and / or a carboxylic anhydride group;
(B) a wax having a carboxyl group and / or a carboxylic anhydride group;
It is characterized by containing.

  Since the non-foamed resin layer A contains an ethylene- (meth) acrylic acid copolymer, the laminated sheet of the present invention having the above characteristics is excellent in scratch resistance. Moreover, since the foaming agent-containing resin layer contains an ethylene-vinyl acetate copolymer having a vinyl acetate content (VA value) of 20% by mass or less, and the component (a) and / or the component (b), The foaming agent-containing resin layer can exhibit sufficient followability for forming bubbles, and is excellent in adhesion to the non-foamed resin layer A. For this reason, in the foamed laminated sheet obtained by foaming the laminated sheet of the present invention, the occurrence of scaly peeling between the non-foamed resin layer A and the foamed resin layer is suppressed, and excellent scratch resistance Can be shown.

  Hereinafter, the layer structure of the laminated sheet and the foamed laminated sheet of the present invention will be described. In the following, the direction in which the foaming agent-containing resin layer and the non-foamed resin layer A are laminated as viewed from the base material is “up” or “ It is referred to as “front surface”, and the opposite direction when viewed from the base material is referred to as “down” or “back surface”.

It does not limit as a base material 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. 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 In the laminated sheet of the present invention, at least a foaming agent-containing resin layer is laminated on a substrate. This foaming agent-containing resin layer can be formed by a known film forming method such as a T-die film forming method or a calendar film forming method.

  The foaming agent-containing resin layer comprises an ethylene-vinyl acetate copolymer (EVA) and the following component (a) and / or component (b): (a) a resin having a carboxyl group and / or a carboxylic anhydride group; b) containing a wax having a carboxyl group and / or a carboxylic anhydride group.

  In the present invention, the ethylene-vinyl acetate copolymer has a vinyl acetate content (hereinafter sometimes referred to as VA value) of 20% by mass or less. By using an ethylene-vinyl acetate copolymer having such a vinyl acetate content, the ease of construction as the wallpaper of the laminated sheet of the present invention and the strength of the foamed resin layer are improved, and the foaming agent-containing resin layer is further improved. However, by containing (a) component and / or (b) component, it is excellent in the adhesiveness of a foaming agent containing resin layer and the non-foamed resin layer A, and extrusion film forming property increases more. The vinyl acetate content is preferably 14% by mass or less, and more preferably 12% by mass or less. The vinyl acetate content is preferably 2% by mass or more, and more preferably 5% by mass or more.

  In the present invention, the vinyl acetate content of the ethylene-vinyl acetate copolymer is a value obtained by dividing the mass of the vinyl acetate unit in the ethylene-vinyl acetate copolymer by the mass of the ethylene-vinyl acetate copolymer. It is a value calculated by multiplying by 100. In addition, when a plurality of ethylene-vinyl acetate copolymers having different vinyl acetate contents are used in combination, the vinyl acetate content in the present invention is relative to all the ethylene-vinyl acetate copolymers to be mixed. By multiplying the vinyl acetate content of each ethylene-vinyl acetate copolymer by the value obtained by dividing the blending ratio (mass%) of each ethylene-vinyl acetate copolymer by 100, and summing the obtained values This is a calculated value.

  The component (a) is a resin having a carboxyl group and / or a carboxylic anhydride group. The component (a) is not particularly limited as long as it is a resin having at least one of a carboxyl group and a carboxylic anhydride group, and a monomer component having at least one of a carboxyl group and a carboxylic anhydride group as a functional group And a resin modified with at least one of carboxylic acid and carboxylic anhydride. In the present invention, from the viewpoint of improving the compatibility with the ethylene-vinyl acetate copolymer in the foaming agent-containing resin layer, as the component (a), olefin, (meth) acrylic acid and / or maleic anhydride and It is preferable to use a copolymer containing olefin and maleic anhydride, and a modified polyolefin resin using (meth) acrylic acid and / or maleic anhydride. Among them, a copolymer containing olefin and maleic anhydride as monomer components is preferably used. Is more preferable. Examples of the olefin include ethylene, propylene, butylene, etc. Among them, ethylene is preferable. In addition, in the copolymer containing (meth) acrylic acid and / or maleic anhydride as a monomer component, the monomer component may constitute a main chain or a graft chain. In this specification, (meth) acrylic acid means acrylic acid and / or methacrylic acid, and other similar expressions are also the same.

  Specific examples of the component (a) include an ethylene- (meth) acrylic acid copolymer, an ethylene-maleic anhydride copolymer, a propylene- (meth) acrylic acid copolymer, a propylene-maleic anhydride copolymer, Ethylene- (meth) acrylic acid-methyl (meth) acrylate copolymer, ethylene-maleic anhydride-methyl (meth) acrylate copolymer, ethylene-propylene- (meth) acrylic acid copolymer, ethylene-propylene -Copolymers such as a maleic anhydride copolymer, and acid-modified resins such as (meth) acrylic acid-modified polyethylene, maleic anhydride-modified polyethylene, (meth) acrylic acid-modified polypropylene, and maleic anhydride-modified polypropylene. As the component (a), these resins may be used alone or in combination of two or more.

  The content of the component (a) in the foaming agent-containing resin layer is preferably 1 to 15 parts by mass, and more preferably 2 to 10 parts by mass based on 100 parts by mass of the polyolefin resin.

  The component (a) preferably has a weight average molecular weight (Mw) of 10,000 to 200,000, more preferably 10,000 to 100,000. In addition, the weight average molecular weight prescribed | regulated by this invention is a value measured by GPC (gel permeation chromatography).

  As for (a) component, it is preferable that MFR (melt flow rate) measured on condition of 190 degreeC and load 21.18N of JISK6922 is 1-30 g / 10min, and it is 2-20. More preferred.

  The component (b) is a wax having a carboxyl group and / or a carboxylic anhydride group. The component (b) is not particularly limited as long as it is a wax having at least one of a carboxyl group and a carboxylic acid anhydride group, and examples thereof include a wax modified with at least one of a carboxylic acid and a carboxylic acid anhydride. . In the present invention, it is preferable to use a modified wax with at least one of (meth) acrylic acid and / or maleic anhydride as the component (b). Among them, use of a modified wax with maleic anhydride is preferable for the melting point and extrusion. It is more preferable because it is suitable for extrusion film formation from the viewpoint of torque reduction. The wax modified with at least one of carboxylic acid and carboxylic acid anhydride is not particularly limited, and paraffin wax, polyethylene wax, polypropylene wax and the like can be used, and among them, polyethylene wax is preferable.

  Specific examples of the component (b) include (meth) acrylic acid modified paraffin wax, maleic anhydride modified paraffin wax, (meth) acrylic acid modified polyethylene wax, maleic anhydride modified polyethylene wax, (meth) acrylic acid modified polypropylene wax. And maleic anhydride-modified polypropylene wax. (B) As a component, these waxes may be used individually by 1 type, and may be used in combination of 2 or more type.

  The content of the component (b) in the foaming agent-containing resin layer is preferably 1 to 10 parts by mass and more preferably 1 to 5 parts by mass with the polyolefin resin as 100 parts by mass.

  The component (b) preferably has a weight average molecular weight (Mw) of 1,000 to 10,000, more preferably 1,500 to 5,000.

  The wax having a carboxyl group and / or carboxylic anhydride group as the component (b) is different from the resin having a carboxyl group and / or carboxylic anhydride group as the component (a) in terms of MFR and weight average. Differentiated by molecular weight. That is, the wax having a carboxyl group and / or a carboxylic acid anhydride group as the component (b) has a very low molecular weight, and the component (b) has such a high fluidity that MFR cannot be measured. Therefore, the resin having a carboxyl group and / or carboxylic anhydride group used as the component (a) is different from the wax having a carboxyl group and / or carboxylic anhydride group used as the component (b). Is shown.

  In the present invention, the resin component (resin component obtained by mixing the ethylene-vinyl acetate copolymer and the component (a) and / or the component (b)) contained in the foaming agent-containing resin layer resin layer is added to the film forming method. Although it depends, it is preferable that MFR (melt flow rate) measured on condition of 190 degreeC and load 21.18N of JISK6922 is 8-20 g / 10min. When the MFR is within the above range, there is little increase in temperature when the foaming agent-containing resin layer is formed by extrusion film formation, and the film can be formed in a non-foamed state. It can be printed on any surface and there are few patterns missing. If the MFR is too large, the resin is too soft, and the resulting foaming agent-containing resin layer may have insufficient scratch resistance.

  The laminated sheet of the present invention is a so-called raw material before foaming having a foaming agent-containing resin layer. The foamed laminate sheet of the present invention is obtained by foaming the foaming agent-containing resin layer.

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

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

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

  When these foaming assistants and (a) component resin are used in combination with (meth) acrylic acid-containing resin and ADCA foaming agent, in the foaming step, the acrylic acid part of (meth) acrylic acid-containing resin and Due to the reaction of the metal-based foaming aid, the effect as the foaming aid may be impaired. Therefore, when a (meth) acrylic acid-containing resin and an ADCA foaming agent are used in combination, it is preferable to use a carboxylic acid hydrazide compound as a foaming aid as described in JP-A-2009-197219. At this time, it is preferable to use about 0.2-1 mass part of carboxylic acid hydrazide compounds with respect to 1 mass part of ADCA foaming agent.

  Examples of the inorganic filler include calcium carbonate, aluminum hydroxide, magnesium hydroxide, antimony trioxide, zinc borate, and a molybdenum compound. By including the inorganic filler, an effect of suppressing see-through, an effect of improving surface characteristics, an effect of suppressing heat generation during combustion, and the like are obtained. 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 5-70 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. Examples of organic pigments include aniline black, perylene black, azo (azo lake, insoluble azo, condensed azo), polycyclic (isoindolinone, isoindoline, quinophthalone, perinone, flavantron, anthrapyrimidine, anthraquinone, quinacridone. Perylene, diketopyrrolopyrrole, dibromoanthanthrone, dioxazine, thioindigo, phthalocyanine, indanthrone, halogenated phthalocyanine). The pigment content is preferably about 10 to 50 parts by mass and more preferably about 15 to 30 parts by mass with respect to 100 parts by mass of the resin component, although it depends on the required color tone density.

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

  In the present invention, the foaming agent-containing resin layer may be a layer that forms a pattern separately from the pattern layer described later. The pigments and resins used are the same as those that can be used in the pattern layer described later.

  The thickness of the foaming agent-containing resin layer is preferably about 40 to 200 μm, and the thickness of the foamed resin layer after foaming in the case of the foaming agent-containing resin layer is preferably about 300 to 1000 μm.

  The total content of the component (a) and the component (b) in the foaming agent-containing resin layer is preferably 2 to 20 parts by mass, and 2.5 to 10 parts by mass with respect to 100 parts by mass of the ethylene-vinyl acetate copolymer. Part is more preferred. When the total content of the component (a) and the component (b) is too large, the foaming agent-containing resin layer becomes hard and it may be difficult to form bubbles, and when it is too small, the surface strength of the laminated sheet may be inferior. There is.

Non-foamed resin layer A
A non-foamed resin layer A is 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.

  The non-foamed resin layer A contains an ethylene- (meth) acrylic acid copolymer. By setting it as the said structure, the non-foaming resin layer A is excellent in scratch resistance, is excellent in adhesiveness with the said foaming agent containing resin layer, and is excellent also in suppression of scaly peeling.

  The content of the ethylene- (meth) acrylic acid copolymer in the non-foamed resin layer A is preferably 70 to 100% by mass, more preferably 80 to 100% by mass, with the non-foamed resin layer A as 100% by mass. By making content of an ethylene- (meth) acrylic acid copolymer into the said range, the non-foamed resin layer A can show the outstanding scratch resistance.

  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.

Non-foamed resin layer B
The back surface (surface on which the base material 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 force with the base material.

  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.

  In the present invention, when the non-foamed resin layer B is provided, 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 this order is also preferable from the viewpoint of manufacturing described later.

Pattern Pattern Layer In the laminated sheet of the present invention, a pattern pattern layer may be formed on the foaming agent-containing resin layer, the non-foamed resin layer A, or a primer layer or a film layer, which will be described later, as 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 non-foamed resin layer A, the design pattern layer, or a film layer described later, if necessary. By forming the primer layer, the adhesion between the layers can be improved.

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

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

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

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

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

  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.

On the film layer non-foamed resin layer A or the design pattern layer may be formed a film layer if necessary. The position where the film layer is formed is not limited, but when the pattern layer is formed, it is preferably formed on the upper surface of the pattern layer. By providing the film layer, the foaming agent-containing resin layer (foamed resin layer) and the pattern layer can be protected, and the surface properties of the laminated sheet can be further improved. Moreover, the adhesiveness between each layer can be improved.

  When the film layer is a transparent resin layer, the resin that can be used for the film layer may be colored as long as it is transparent. When the transparent resin layer is formed on the front surface of the pattern layer, it may be translucent as long as the pattern layer is visible.

  The film layer is preferably a layer containing polyethylene and / or an ethylene copolymer. Polyethylene and / or ethylene copolymers include copolymers of ethylene and α-olefins having 4 or more carbon atoms (linear low density polyethylene), ethylene- (meth) acrylic acid copolymers, ethylene-methyl (meth) acrylates. Copolymer, ethylene (meth) acrylic acid copolymer such as ethylene-ethyl (meth) acrylate copolymer, ethylene-vinyl acetate copolymer (EVA), ethylene-vinyl alcohol copolymer (EVOH), ethylene -Saponified vinyl acetate copolymer, ionomer and the like can be mentioned. In the present invention, it is particularly preferable to use an ethylene-vinyl alcohol copolymer.

  Although the thickness of a film layer is not specifically limited, Generally about 3-30 micrometers is preferable and about 5-20 micrometers is more preferable.

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

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

  When a surface protective layer is formed for the purpose of surface strength (scratch resistance, etc.), contamination resistance, pattern layer protection, etc. of laminated sheets, those containing ionizing radiation curable resins as resin components are suitable. is there. The ionizing radiation curable resin is preferably one that undergoes radical polymerization (curing) by electron beam irradiation. The thickness of the surface protective layer is not limited, but is preferably about 0.1 to 15 μm.

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 a base material). Embossing can be performed by known means such as pressing an embossed plate. For example, when the outermost surface layer is a surface protective layer, a desired embossed pattern can be formed by pressing the embossed plate after heat-softening the front surface. 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. The heating conditions at the time of foaming are not limited as long as the foamed resin layer is formed by the decomposition of the pyrolytic foaming agent. The heating temperature is preferably about 210 to 240 ° C., and the heating time is preferably about 20 to 80 seconds. The foaming ratio of the foamed resin layer is preferably 6 times or more, and more preferably about 7 to 10 times. By setting the expansion ratio within the above range, the amount of resin used can be reduced, the cost can be reduced, and the nonflammability of the foamed laminated sheet can be increased.

≪Laminated sheet and foamed laminated sheet manufacturing method≫
The method for producing a laminated sheet is not particularly limited, for example, a method for producing a laminated sheet having a step of laminating at least a foaming agent-containing resin layer and a non-foamed resin layer A on a substrate,
(1) The non-foamed resin layer A contains an ethylene- (meth) acrylic acid copolymer,
(2) The foaming agent-containing resin layer comprises an ethylene-vinyl acetate copolymer having a vinyl acetate content (VA value) of 20% by mass or less, the following component (a) and / or component (b):
(A) a resin having a carboxyl group and / or a carboxylic anhydride group;
(B) a wax having a carboxyl group and / or a carboxylic anhydride group;
Containing,
The manufacturing method of the lamination sheet characterized by this is mentioned.

  Although it does not specifically limit as a manufacturing method of a foaming laminated sheet, The manufacturing method of the foaming laminated sheet characterized by making the foaming agent containing resin layer of the said laminated sheet foam by heating is mentioned.

  When forming the non-foamed resin layer A on one side of the foaming agent-containing resin layer, or when forming the non-foamed resin layers A and B on both sides of the foaming agent-containing resin layer, co-extrusion film formation by a T-die extruder Is preferred. For example, when a non-foamed resin layer is formed 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.

  In addition, when an inorganic filler is contained in the resin composition forming the foaming agent-containing resin layer and the foaming agent-containing resin layer is formed by extrusion film formation, an extrusion port (so-called die) of the extruder is used. Inorganic filler residues (so-called eyes and eyes) are easily generated, and this tends to be a foreign matter on the surface of the foaming agent-containing resin layer. Therefore, when an inorganic filler is contained in the resin composition forming the foaming agent-containing resin layer, it is preferable to form a three-layer coextrusion film as described above. That is, it is possible to suppress the occurrence of the above-mentioned corners by co-extrusion film formation in a mode in which the foaming agent-containing resin layer is sandwiched between non-foamed resin layers.

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

  On the foaming agent-containing resin layer, if necessary, a pattern layer, a film layer and a primer layer are formed in any order, and if necessary, a surface protective layer is formed to form a laminated sheet, followed by heat treatment And a foaming lamination sheet is obtained by making a foaming agent containing resin layer into a foaming resin layer. In FIG. 1, the layer structure of the lamination sheet which laminated | stacked the non-foaming resin layer B, the foaming agent containing resin layer, the non-foaming resin layer A, the design pattern layer, the primer layer, and the surface protective layer in order on the base material is illustrated. Each of these layers can be laminated by combining coating such as printing and coating, extrusion film formation and the like, and coating such as printing and coating can be performed according to a conventional method.

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

The laminated sheet of the present invention has a layer structure in which at least a foaming agent-containing resin layer and a non-foamed resin layer A are laminated in this order on a substrate. Since it contains a coalescence, it has excellent scratch resistance. Further, the foaming agent-containing resin layer comprises an ethylene-vinyl acetate copolymer having a vinyl acetate content (VA value) of 20% by mass or less, and the following component (a) / and / or (b):
(A) a resin having a carboxyl group and / or a carboxylic anhydride group;
(B) a wax having a carboxyl group and / or a carboxylic anhydride group;
Containing. For this reason, the foaming agent-containing resin layer can exhibit sufficient followability for forming bubbles and is excellent in adhesion to the non-foamed resin layer A. Thereby, in the foamed laminated sheet obtained by foaming the laminated sheet of the present invention, the occurrence of scaly peeling between the non-foamed resin layer A and the foamed resin layer is suppressed, and excellent scratch resistance Can be shown.

It is a schematic diagram which shows an example of the layer structure of the lamination sheet of this invention.

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

(Preparation of foaming agent-containing resin layer)
The resin composition prepared according to the formulation shown in Table 1 is kneaded using a lab plast mill (manufactured by HAAKE) at a temperature of 110 ° C., a rotor rotation speed of 50 rpm, and a kneading time of 10 minutes to form a foaming agent-containing resin layer. A resin composition was obtained.

  Using the resin composition for forming the obtained foaming agent-containing resin layer, the foaming agent-containing resin layer was prepared by press molding to a thickness of 80 μm.

(Preparation of non-foamed resin layers A and B)
The resin composition shown in Table 2 is laminated on the surface of the foaming agent-containing resin layer with a thickness of 5 μm, and the non-foaming resin layer A, the foaming agent-containing resin layer, and the non-foaming resin layer B are laminated in this order. A flat film-like resin sheet was obtained.

The obtained flat film-like resin sheet was laminated on 65 g / m ² backing paper (WK-665: manufactured by KJ special paper). This state is referred to as the original fabric α.

  Next, electron beam irradiation (195 KV 30 KGy) was performed from the non-foamed resin layer A side of the raw fabric α to prepare a laminated sheet.

  Finally, it was put into a gear oven heated to 220 ° C. for 35 seconds to foam the foaming agent-containing resin layer to obtain a foamed resin layer, thereby preparing a foamed laminated sheet.

Test example 1 (flaky peel evaluation test)
The state of the surface of the foamed laminated sheet produced in Examples and Comparative Examples was visually observed to evaluate the presence or absence of scaly peeling.

Test example 2 (scratch resistance test)
About the foaming lamination sheet produced by the Example and the comparative example, it tested according to the performance evaluation method of the surface reinforcement | strengthening wallpaper established by the wallpaper industry association, and evaluated based on the following evaluation criteria.
○: No change on the surface.
Δ: Only the surface layer was damaged.
X: The wound reached the foamed resin layer.

  The results of Test Example 1 and Test Example 2 are shown in Table 3.

1. Base material 2. Non-foamed resin layer B
3. 3. Foaming agent-containing resin layer Non-foamed resin layer A
5. Pattern layer 6 Primer layer 7. Surface protective layer

Claims (7)

A laminated sheet in which at least a foaming agent-containing resin layer and a non-foamed resin layer A are laminated in this order on a substrate,
(1) The non-foamed resin layer A contains an ethylene- (meth) acrylic acid copolymer,
(2) The foaming agent-containing resin layer comprises an ethylene-vinyl acetate copolymer having a vinyl acetate content (VA value) of 14% by mass or less, the following component (a) and / or component (b):
(A) a resin having a carboxyl group and / or a carboxylic anhydride group;
(B) a wax having a carboxyl group and / or a carboxylic anhydride group;
Containing the door,
(3) The total content of the component (a) and the component (b) in the foaming agent-containing resin layer is 10 parts by mass or less with respect to 100 parts by mass of the ethylene-vinyl acetate copolymer.
A laminated sheet characterized by that. The total content of the component (a) and the component (b) in the foaming agent-containing resin layer is 2 to 5 parts by mass with respect to 100 parts by mass of the ethylene-vinyl acetate copolymer. The laminated sheet according to 1.   The component (a) is selected from a copolymer containing an olefin, (meth) acrylic acid and / or maleic anhydride as monomer components, and a modified polyolefin resin with (meth) acrylic acid and / or maleic anhydride. The laminated sheet according to claim 1 or 2, which is at least one kind.   The laminated sheet according to any one of claims 1 to 3, wherein the component (b) is a modified wax with (meth) acrylic acid and / or maleic anhydride.   The said foaming agent containing resin layer is a laminated sheet in any one of Claims 1-4 which has the non-foaming resin layer B in the surface on the opposite side to the surface in which the said non-foaming resin layer A is formed.   The foaming lamination sheet obtained by foaming the said foaming agent containing resin layer of the lamination sheet in any one of Claims 1-5.   The foamed laminated sheet according to claim 6, wherein embossing is performed from above the outermost surface layer.

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