JP2007270387A - Foamed wallpaper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide non-vinyl chloride foamed wallpaper having an expansion ratio sufficient to exhibit good flame retardance and designability. <P>SOLUTION: The foamed wallpaper comprises at least a foamed resin layer formed on a paper-like substrate. (1) The foamed resin layer is a layer formed by foaming a foaming agent-containing resin layer and (2) the foaming agent-containing resin layer is a layer formed by a resin composition containing a polymer obtained by using at least one kind of acrylic acid and methacrylic acid as a monomer. (3) The foaming agent-containing resin layer contains a silicone-based flame retardant in an amount of 3-5 pts.wt. based on 100 pts.wt. of a resin component. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a foam wallpaper having good flame retardancy.

  Foamed wallpaper, which is one of the building interior materials, is required to be flame retardant from the standpoint of fire safety, and a certain level of flame retardancy is often determined by the Building Standards Act.

  Conventionally, vinyl chloride is frequently used as a resin component contained in foamed wallpaper. Thus, in the foamed wallpaper containing vinyl chloride, the resin component exhibits flame retardancy by containing halogen. Moreover, the foamed wallpaper containing vinyl chloride has good surface properties such as scratch resistance and abrasion resistance.

  On the other hand, foamed wallpaper containing vinyl chloride has the disadvantage that it easily generates harmful gases during a fire or incineration because it contains halogen.

  In view of the recent increase in environmental awareness, foamed wallpaper containing no halogen has been demanded, and various types have been proposed. Thus, since the foamed wallpaper which does not contain a halogen does not have flame retardancy per se, it is necessary to contain a flame retardant. As the flame retardant, aluminum hydroxide, magnesium hydroxide, or the like, which does not generate harmful gas during a fire or combustion and is low smoke and non-polluting, is generally used. For example, Patent Document 1 discloses a non-vinyl chloride foam wallpaper containing aluminum hydroxide, magnesium hydroxide or the like as a flame retardant.

However, the foamed wallpaper containing aluminum hydroxide, magnesium hydroxide or the like as shown in Patent Document 1 must contain a large amount of flame retardant in order to exhibit predetermined flame retardancy. Problems arise. That is, when a large amount of flame retardant is contained, the kneadability of the resin composition before film formation in extrusion film formation is poor. In addition, since the ratio of the resin component in the foamed resin layer is reduced, the foamed resin layer becomes porous and gas escape occurs, and the foaming ratio cannot be sufficiently obtained. As a result, the design property is also lowered.
JP-A-10-193538 (particularly [0014] paragraph)

  An object of this invention is to provide the non-vinyl chloride foam wallpaper which has sufficient flame retardance and a foaming ratio sufficient to exhibit the designability.

  As a result of intensive studies, the present inventors have found that the above object can be achieved by a combination of a specific resin component and a flame retardant, and have completed the present invention.

  That is, the present invention relates to the following foamed wallpaper.

1. A foamed wallpaper in which at least a foamed resin layer is formed on a paper substrate,
(1) The foamed resin layer is a layer formed by foaming the foaming agent-containing resin layer,
(2) The foaming agent-containing resin layer is a layer formed of a resin composition containing a polymer obtained by using at least one of acrylic acid and methacrylic acid as a monomer,
(3) The foaming wallpaper, wherein the foaming agent-containing resin layer contains 3 to 5 parts by weight of a silicon flame retardant with respect to 100 parts by weight of the resin component.

  2. The foamed wallpaper according to Item 1, wherein the polymer is a copolymer obtained by combining ethylene with at least one monomer of acrylic acid and methacrylic acid.

  3. Item 2. The foamed wallpaper according to Item 1, wherein the polymer is a copolymer obtained by combining at least one monomer of acrylic acid and methacrylic acid with ethylene and an unsaturated ester.

  4). The foamed wallpaper according to any one of Items 1 to 3, further comprising a non-foamed resin layer, wherein the non-foamed resin layer is formed so as to be a foamed resin layer and a non-foamed resin layer in order from the paper-based substrate. .

  5. Item 5. The foamed wallpaper according to any one of Items 1 to 4, wherein a non-foamed resin layer is further formed between the paper substrate and the foamed resin layer.

6). Item 6. The foamed wallpaper according to any one of Items 1 to 5, wherein the sheet is embossed from the top surface layer.

Hereinafter, the foamed wallpaper of the present invention will be described in detail.

The foamed wallpaper of the present invention has at least a foamed resin layer formed on a paper-based substrate,
(1) The foamed resin layer is a layer formed by foaming the foaming agent-containing resin layer,
(2) The foaming agent-containing resin layer is a layer formed of a resin composition containing a polymer obtained by using at least one of acrylic acid and methacrylic acid as a monomer,
(3) The foaming agent-containing resin layer is characterized by containing 3 to 5 parts by weight of a silicon flame retardant with respect to 100 parts by weight of the resin component.

The material of the paper base is not particularly limited as long as it has mechanical strength, heat resistance and the like suitable as a wallpaper base, and a fiber sheet can be generally used.

  Specifically, among fiber sheets, flame retardant paper (pulp-based sheets treated with flame retardants such as guanidine sulfamate and guanidine phosphate); inorganic additives such as aluminum hydroxide and magnesium hydroxide Inorganic paper including; fine paper; thin paper and the like.

The basis weight of the paper quality substrate is not limited, but preferably about 50 to 300 g / ^{m 2,} about 50 to 80 g / ^{m 2} is more preferable.

Non-foamed resin layer B
In the present invention, a non-foamed resin layer (non-foamed resin layer B) may be formed between the paper substrate and the foamed resin layer as necessary. In particular, when the non-foamed resin layer B is formed as an adhesive layer, excellent adhesion can be obtained. As the non-foamed resin layer B, for example, an ethylene-vinyl acetate copolymer or the like can be suitably used. The non-foamed resin layer B may contain known additives in addition to the resin component, but is preferably blended so that the content of the resin component is 70 to 100% by weight.

Foamed resin layer The foamed resin layer is a layer formed by foaming the foaming agent-containing resin layer.

  The foaming agent-containing resin layer may be cross-linked by electron beam irradiation. Thereby, excellent surface strength and the like can be achieved. In the present invention, not only the foaming agent-containing resin layer, but also other layers that can be crosslinked by electron beam irradiation may be crosslinked. Moreover, when bridge | crosslinking, you may make a foaming agent containing resin layer contain a crosslinking adjuvant.

The foaming agent-containing resin layer is formed of a resin composition containing, as a resin component, a polymer obtained using at least one of acrylic acid (CH ₂ ═CHCOOH) and methacrylic acid (CH ₂ ═C (CH ₃ ) COOH) as a monomer. Layer.

As the polymer (the polymer of the present invention) obtained using at least one of acrylic acid (CH ₂ ═CHCOOH) and methacrylic acid (CH ₂ ═C (CH ₃ ) COOH) as a monomer, for example, acrylic acid and methacrylic acid A copolymer obtained by a combination of at least one monomer and ethylene can be suitably used. More specifically, at least one of an ethylene-methacrylic acid copolymer, an ethylene-acrylic acid copolymer, an ethylene-methacrylic acid-unsaturated ester copolymer and an ethylene-acrylic acid-unsaturated ester copolymer is preferable. Among these, particularly when processing at a low temperature, an ethylene-methacrylic acid copolymer and an ethylene-acrylic acid copolymer are preferable.

  Examples of the unsaturated ester include, but are not limited to, alkyl esters of acrylic acid or methacrylic acid. Examples of the alkyl ester of acrylic acid include methyl acrylate, ethyl acrylate, isopropyl acrylate, isobutyl acrylate, n-butyl acrylate, and 2-ethylhexyl acrylate. Examples of the alkyl ester of methacrylic acid include methyl methacrylate, ethyl methacrylate, ethyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, methacrylic acid-n-butyl, and methacrylic acid-2-ethylhexyl.

  When such a resin component is used, it is possible to form a strong layer particularly due to hydrogen bonds in the resin, so that excellent scratch resistance, wear resistance, and the like can be obtained. These may be known or commercially available.

  The content of acrylic acid or methacrylic acid in the copolymer is preferably about 4 to 20% by weight. Such a resin can also use a commercial item. A known additive can also be blended in the resin composition.

  The melt flow rate value (JIS K7210: 190 ° C., 2.16 kg) of the resin component depends on the type of polymer used, but is usually preferably 60 to 200 g / 10 minutes. The present invention is particularly advantageous in that a good foamed state can be maintained even in a high range of 100 to 200 g / 10 minutes.

  In addition, MFR of this specification is the value measured by the test method of JISK7210 (flow test method of thermoplastics). As test conditions, “190 ° C., 21.18 N (2.16 kgf)” described in JIS K 6760 is adopted.

  The content of the polymer of the present invention in the resin composition is not limited, but it is preferably set appropriately within the range of usually 80 to 100% by weight (particularly 80 to 95% by weight).

  As the resin composition, for example, a resin composition containing an ethylene-methacrylic acid copolymer (EMAA), a silicon flame retardant, a foaming agent, an inorganic filler (excluding the flame retardant), a pigment, and a cell modifier is suitable. Can be used. In addition, stabilizers, lubricants, petroleum resins, and the like can be used as additives.

  As the foaming agent, a thermally decomposable foaming agent can be suitably used. The pyrolytic foaming agent can be selected from known foaming agents. For example, azo compounds such as azodicarbonamide (ADCA) and azobisformamide; and bidazides such as oxybenzenesulfonyl hydrazide (OBSH) and paratoluenesulfonyl hydrazide. The content of the pyrolytic foaming agent can be appropriately set according to the type of foaming agent, the expansion ratio, and the like. From the viewpoint of the expansion ratio, it is 1.5 times or more, preferably about 3 to 7 times, and the pyrolytic foaming agent is preferably about 1 to 20 parts by weight with respect to 100 parts by weight of the resin component. .

  As the cell adjusting agent, for example, a metal soap such as zinc stearate can be used. The content of the cell modifier is preferably about 0.3 to 10 parts by weight and more preferably about 1 to 5 parts by weight with respect to 100 parts by weight of the resin component.

  Examples of inorganic fillers (excluding flame retardants) include calcium carbonate. By including an inorganic filler, an effect of suppressing see-through, an effect of improving surface characteristics, and the like are obtained. About 0-100 weight part is preferable with respect to 100 weight part of resin components, and, as for content of an inorganic filler, about 20-70 weight part 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 Inorganic pigments such as ultramarine, bitumen, cobalt blue, chromium oxide, cobalt green, aluminum powder, bronze powder, titanium mica, and zinc sulfide; for example, aniline black, perylene black, azo (azo lake, insoluble azo, condensed azo), Polycyclic (isoindolinone, isoindoline, quinophthalone, perinone, flavantron, anthrapyrimidine, anthraquinone, quinacridone, perylene, diketopyrrolopyrrole, dibromoanthanthrone, dioxazine, thioindigo, phthalocyanine, indanthro , And organic pigments halogenated phthalocyanine), or the like. The content of the pigment is preferably about 10 to 50 parts by weight and more preferably about 15 to 30 parts by weight with respect to 100 parts by weight of the resin component.

  A silicon-based flame retardant is used as the flame retardant. In the present invention, 1 to 10 parts by weight (preferably 3 to 5 parts by weight) of a silicon flame retardant is used with respect to 100 parts by weight of the resin component. Such a silicon flame retardant exhibits good flame retardancy even when added in a small amount.

  Moreover, in this invention, petroleum resin may be included. Although it does not restrict | limit especially as a petroleum resin, A hydrogenated petroleum resin can be used suitably. As the hydrogenated petroleum resin, it is preferable to use, for example, an alicyclic saturated hydrocarbon resin obtained by hydrogenating an aromatic petroleum resin. As this resin, known or commercially available resins can be used.

  The thickness of the foaming agent-containing resin layer is not limited, but is preferably about 10 to 50 μm, more preferably about 10 to 20 μm.

  The foamed state of the foamed resin layer (for example, the size of foamed cells, the density of foamed cells, etc.) is not limited, and can be appropriately designed according to the type and use of the foamed wallpaper. What is necessary is just to implement according to the method described in the manufacturing method of the postscript as a method of foaming a foaming agent containing resin layer.

Non-foamed resin layer A
The non-foamed resin layer (non-foamed resin layer A) mainly protects the foamed resin layer. In the present invention, a layer formed of a resin composition containing, as a resin component, a polymer obtained using at least one of acrylic acid (CH ₂ ═CHCOOH) and methacrylic acid (CH ₂ ═C (CH ₃ ) COOH) as a monomer. Is preferably a non-foamed resin layer.

  As the resin component, for example, a copolymer obtained by a combination of at least one monomer of acrylic acid and methacrylic acid and ethylene can be suitably used as the resin component. More specifically, it is desirable to use at least one of an ethylene-methacrylic acid copolymer, an ethylene-acrylic acid copolymer, and an ionomer resin. As the ionomer resin, a resin having a structure in which the molecules of ethylene-methacrylic acid copolymer and / or ethylene-acrylic acid copolymer are intermolecularly bonded with metal ions such as sodium and zinc can be used. When such a resin component is used, it is possible to form a strong layer particularly due to hydrogen bonds in the resin, so that excellent scratch resistance, wear resistance, and the like can be obtained. These may be known or commercially available.

  The content of acrylic acid or methacrylic acid in the copolymer is preferably about 4 to 15% by weight. Such a resin can also use a commercial item. A known additive can also be blended in the resin composition.

  The thickness of the non-foamed resin layer is not limited, but is preferably about 10 to 50 μm, more preferably about 10 to 20 μm.

  Moreover, although content of the said resin component in a resin composition is not limited, Usually, it is preferable to set suitably in the range of 70 to 100 weight%.

  Although the melt flow rate value of the resin component depends on the type of the resin component to be used, etc., it is generally set as appropriate within a range of 10 g / 10 min or more. Usually, it is preferably 10 to 100 g / 10 minutes, particularly preferably 10 to 95 g / 10 minutes, and more preferably 20 to 80 g / 10 minutes. By using a material having such a numerical range, more excellent scratch resistance, wear resistance and the like can be obtained.

Pattern Pattern Layer The sheet of the present invention may have a pattern pattern layer on the front surface of the non-foamed resin layer A as necessary.

  The pattern layer imparts design properties to the foamed wallpaper. Examples of the design pattern include a wood 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, and an abstract pattern. The pattern can be selected according to the type of foam wallpaper.

  The pattern pattern layer can be formed, for example, by printing a pattern pattern on the front surface of the non-foamed resin layer. In addition, when forming a picture pattern layer, you may form a primer layer previously as needed. Examples of printing methods 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 (or a dispersion medium) 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 is, for example, an acrylic resin, a styrene resin, a polyester resin, a urethane resin, a chlorinated polyolefin resin, a vinyl chloride-vinyl acetate copolymer resin, a polyvinyl butyral resin, an alkyd resin, or a petroleum resin. Examples include resins, ketone resins, epoxy resins, melamine resins, fluorine resins, silicone resins, fiber derivatives, rubber resins, 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.

  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.

Surface protective layer (overcoat layer)
The sheet of the present invention may have a surface protective layer on the surface of the pattern layer for the purpose of adjusting the gloss and / or protecting the pattern layer. The kind of surface protective layer is not limited. If it is a surface protective layer aiming at gloss adjustment, there exists a surface protective layer containing known fillers, such as a silica, for example. As a method for forming the surface protective layer, a known method such as gravure printing can be employed. In addition, when the adhesiveness of a pattern pattern layer and a surface protective layer is not fully acquired, a surface protective layer can also be provided after carrying out the adhesion process (primer process) of the surface of a pattern pattern layer.

  When the surface protective layer is formed for the purpose of surface strength of the sheet (such as scratch resistance), stain resistance, and protection of the pattern layer, it is preferable to contain an ionizing radiation curable resin as a resin component. . The ionizing radiation curable resin is preferably one that undergoes radical polymerization (curing) by electron beam irradiation.

  The thickness of the surface protective layer is not limited, but is preferably about 0.1 to 15 μm.

The embossed invention sheet may be appropriately provided with an embossed pattern. In this case, embossing may be performed from the top surface layer of the sheet (on the side opposite to the paper-based substrate). 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 grain texture, a hairline, and a multiline groove.

<Method for producing foam wallpaper>
The manufacturing method of this invention sheet | seat is not specifically limited. For example, in order to produce a foamed wallpaper having a foamed resin layer and a non-foamed resin layer A on a paper substrate, coextrusion with a T-die extruder is suitable. A multi-manifold type T-die capable of simultaneously forming two layers by simultaneously extruding molten resin corresponding to two layers can be used. In this case, the resin composition for forming the foaming agent-containing resin layer and the resin composition for forming the non-foamed resin layer are placed in separate cylinders, and two types and two layers are simultaneously extruded to form and laminate. That's fine. In this method, the coextruded laminate is simultaneously laminated (film formation) on a paper-based substrate. The resin layer laminated simultaneously with extrusion on the paper base is bonded to the paper base because it has adhesiveness by heat melting.

  Alternatively, a laminate in which two types and two layers are simultaneously formed in advance may be prepared, placed on a paper substrate, and bonded to the paper substrate by heat lamination.

  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 molding, an extrusion port (so-called die) of an extrusion molding machine is used. Inorganic filler residues (so-called eyes and eyes) are likely to occur, and this tends to be a foreign matter on the sheet surface. Therefore, when the inorganic filler is contained in the resin composition forming the foaming agent-containing resin layer, the non-foaming resin layer A and the non-foaming resin layer B can be coextruded together with the foaming agent-containing resin layer. preferable. The coextrusion molding can be performed, for example, by using a multi-manifold type T die. Thus, by simultaneously extruding and molding the foaming agent-containing resin layer between the non-foamed resin layers, it is possible to suppress the occurrence of the eyes.

  After simultaneous lamination on the paper substrate, the foamed resin layer is formed by heating the foaming agent-containing resin layer. The heating conditions 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.

  Electron beam irradiation may be performed before the heat treatment. Thereby, since the resin component can be crosslinked, the surface strength of the foamed wallpaper, the degree of foaming, etc. can be controlled. The energy of the electron beam is preferably about 150 to 250 kV. The irradiation amount is preferably about 1 to 7 Mrad. A known electron beam irradiation apparatus can be used as the electron beam source. Crosslinking can also be performed using a chemical crosslinking agent (also referred to as a crosslinking agent or a crosslinking aid).

  In the case of performing electron beam irradiation, the composition may contain a crosslinking agent. Any crosslinking agent that promotes crosslinking by electron beam irradiation may be used. Examples thereof include polyfunctional monomers such as neopentyl glycol dimethacrylate and trimethylolpropane trimethacrylate, oligomers, and the like. The crosslinking agent is preferably about 0 to 10 parts by weight, more preferably 1 to 4 parts by weight, based on 100 parts by weight of the resin component.

  When a surface protective layer containing an ionizing radiation curable resin is formed, the surface protective layer can be cured by electron beam irradiation. Such electron beam irradiation can be performed simultaneously (same processing) as electron beam irradiation performed to crosslink the resin contained in the foaming agent-containing resin layer. That is, after forming a foaming agent-containing resin layer, a non-foaming resin layer, a pattern layer, and a surface protective layer containing an ionizing radiation curable resin in this order, the resin contained in the foaming agent-containing resin layer is irradiated with an electron beam. The resin contained in the surface protective layer can be cured while being crosslinked.

  When producing a foam wallpaper having a pattern layer, it is preferable to form the pattern layer on the surface of the non-foamed resin layer before the heat treatment. The pattern pattern layer may be formed as described above.

  Since the foamed wallpaper of the present invention uses a silicon-based flame retardant as a flame retardant, it avoids high filling and exhibits good expansion ratio and flame retardancy. Moreover, it has favorable curl resistance by combination with a specific resin component.

  Such foamed wallpaper can be manufactured satisfactorily by kneading processability and film formation according to the hot melt extrusion method.

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

Example 1 (Production of foamed wallpaper)
Using a three-type three-layer multi-manifold T-die extruder, i) a non-foamed resin layer / ii) a foaming agent-containing resin layer / iii) a non-foamed resin layer in this order to form a film thickness of 10 μm / 100 μm / 10 μm, A backing paper was laminated on the surface of the iii) layer. Extrusion conditions at this time were as follows: i) layer resin had a cylinder temperature of 130 ° C., ii) layer resin had a cylinder temperature of 120 ° C., and iii) layer resin had a cylinder temperature of 100 ° C. In either case, the die temperature was 120 ° C. Next, an electron beam (200 KV, 30 kGy) was irradiated from above the i) layer, the i) layer and the ii) layer were crosslinked with resin, and a corona discharge treatment was performed on the i) layer. Furthermore, pattern printing was performed by a gravure printing machine. Next, the foaming agent contained in the foaming agent-containing resin layer was foamed by heating in a gear oven (240 ° C. × 45 seconds). Further, the foam was embossed with a textured pattern to obtain a desired wallpaper.

  Each layer was formed using the following components.

  The non-foamed resin layer i) was formed from an ethylene-methacrylic acid copolymer “Nucleel N1560H (MFR = 60, MA = 15%): manufactured by Mitsui DuPont Polychemicals”.

  The foamed resin layer ii) is composed of 100 parts by weight of an ethylene-methacrylic acid copolymer “Nucleel N1110H (MFR = 100, MA = 11%): Mitsui DuPont Polychemical”, a fluidity modifier “Alcon P-100: "Arakawa Chemical" 20 parts by weight, silicon flame retardant "DC4-7081: Toray Dow Corning" 3 parts by weight, titanium dioxide "R-108: DuPont" 20 parts by weight, foaming agent "Vinihole AC # 3: Eiwa Chemical Industries" The resin composition contains 5 parts by weight, 3 parts by weight of foaming aid “SP-148: manufactured by Eishin Kasei Kogyo”, and 0.5 parts by weight of crosslinking aid “OPSTA JUA-702: made by JSR”. As the resin composition, pellets obtained by strand cutting after kneading the respective components were used.

  The non-foamed resin layer iii) was formed of EVA resin “Evaflex V150 (MFR = 30, VA = 33%): manufactured by Mitsui DuPont Polychemicals”.

Comparative Example 1
A foamed wallpaper was prepared in the same manner as in Example 1 except that no flame retardant was added.

Comparative Example 2
A foamed wallpaper was obtained in the same manner as in Example 1 except that calcium carbonate and a flame retardant were not blended.

Comparative Example 3
A foam wallpaper was prepared in the same manner as in Example 1 except that the flame retardant was 40 parts by weight of aluminum hydroxide “C-303, manufactured by Sumitomo Chemical”.

Test example 1
About the Example and the comparative example, the kneadability at the time of manufacture, extrusion film forming property, and the flame retardance of the produced foamed wallpaper were evaluated. The results are shown in Table 1 below.

Each physical property in Table 1 was evaluated by the following methods.
(1) Kneading workability when preparing resin composition pellets The compound state and workability during kneading were confirmed.
○: There is no foaming during processing, and pellet production is easy.
Δ: Although there is no foaming during processing, pellet preparation is not easy.
X: Foamed during processing and pellets cannot be produced.
(2) Extrusion film-forming property The cross section of the extruded resin sheet (particularly the foaming agent-containing resin layer) was evaluated by visual observation.
○: Appearance is good (foaming is not observed, and dispersion of inorganic components such as inorganic fillers is good)
Δ: poor appearance (fine foaming is observed or inorganic component such as an inorganic filler is poorly dispersed)
×: Film cannot be formed (extrusion film cannot be formed)
(3) Flame retardance Foamed wallpaper (sheet) is bonded to a 9.5 mm thick gypsum board using starch paste, and a corn calorimeter (manufactured by Toyo Seiki Co., Ltd.) is used to conduct a combustion test in accordance with ISO 5660. went. The evaluation criteria were as follows.
○… 200kW / m ² excess duration is less than 9 seconds and total calorific value is 7MJ / m ² or less.
Δ: 200 kW / m ² excess duration is 9 to 10 seconds and total calorific value is 7 to 8 MJ / m ² .
×… 200 kW / m ² excess duration is 10 seconds or more, or total calorific value is 8 MJ / m ² or more.

Claims (6)

A foamed wallpaper in which at least a foamed resin layer is formed on a paper substrate,
(1) The foamed resin layer is a layer formed by foaming the foaming agent-containing resin layer,
(2) The foaming agent-containing resin layer is a layer formed of a resin composition containing a polymer obtained by using at least one of acrylic acid and methacrylic acid as a monomer,
(3) The foaming wallpaper, wherein the foaming agent-containing resin layer contains 3 to 5 parts by weight of a silicon flame retardant with respect to 100 parts by weight of the resin component.   The foamed wallpaper according to claim 1, wherein the polymer is a copolymer obtained by a combination of at least one monomer of acrylic acid and methacrylic acid and ethylene.   The foamed wallpaper according to claim 1, wherein the polymer is a copolymer obtained by a combination of at least one monomer of acrylic acid and methacrylic acid, ethylene and an unsaturated ester.   The foamed wallpaper according to any one of claims 1 to 3, further comprising a non-foamed resin layer, wherein the non-foamed resin layer is formed so as to be a foamed resin layer and a non-foamed resin layer in order from a paper-based substrate. .   The foamed wallpaper according to any one of claims 1 to 4, wherein a non-foamed resin layer is further formed between the paper-based substrate and the foamed resin layer.   The foamed wallpaper according to any one of claims 1 to 5, wherein embossing is performed from above the outermost surface layer of the sheet.