JP4816369B2 - Foam wallpaper - Google Patents

Description

  The present invention relates to foamed wallpaper useful for wall decoration.

  Conventionally, foamed wallpaper (foamed decorative sheet) is known in which a foamed resin layer of vinyl chloride resin is formed on a paper-based substrate (backing paper). In recent years, in consideration of the environment, halogen-free resins such as ethylene-vinyl acetate copolymer resin (EVA), acrylic resin, and olefin resin have been used for the foamed resin layer (Patent Document 1). ~ 3 etc.).

  Foamed wallpaper is required to have excellent surface strength (for example, scratch resistance). Therefore, in order to increase the surface strength, it has been proposed to use an ethylene-methacrylic acid copolymer (EMAA) as a resin component contained in the foamed resin layer.

  The foamed resin layer is formed, for example, by foaming a foaming agent-containing resin layer containing a pyrolytic foaming agent by heating. The foaming agent-containing resin layer is formed, for example, by forming a resin composition containing a pyrolytic foaming agent by melt extrusion according to an extrusion method.

  In the case where a foaming agent-containing resin layer is formed by the extrusion method and foamed to form a foamed resin layer, there are the following problems. That is, EMAA has a carboxylic acid in the molecule, and therefore has a hydrogen bond between the molecules, and thus requires high-temperature heating in order to ensure the fluidity of the resin composition suitable for extrusion. If the heating is lowered, there is room for using another pyrolytic foaming agent, but in that case, the fluidity of the resin composition becomes insufficient and the film-forming property is hindered. For this reason, there is a problem that only an azodicarbonamide (ADCA) type foaming agent having a high foaming start temperature can be used as the pyrolytic foaming agent. Moreover, since the ADCA foaming agent is used, the ADCA foaming agent and the EMAA resin react with each other in the foaming step, and the foamed resin layer turns yellow. This yellowing leads to a decrease in the design of the foamed wallpaper.

Therefore, a foamed wallpaper obtained by forming a foaming agent-containing resin layer by melt extrusion of a resin composition containing EMAA, and further foaming the foaming agent-containing resin layer to form a foamed resin layer, Development of a foam wallpaper that is suppressed in generation and has good film-forming properties is desired.
Japanese Patent Laid-Open No. 6-47875 JP 2000-255011 A JP 2001-347611 A

  The present invention is a foam wallpaper obtained by forming a foaming agent-containing resin layer by melt extrusion of a resin composition containing EMAA, and further foaming the foaming agent-containing resin layer to form a foamed resin layer. The present invention provides a foamed wallpaper in which the occurrence of deformation is suppressed and the film forming property is good.

  As a result of extensive research, the present inventor has set a resin composition for forming a foaming agent-containing resin layer in a specific range with a melt flow rate (MFR) of a resin composition at a lower temperature than in the past. When it is possible to melt-extrusion, it is possible to use not only ADCA foaming agents but also oxybisbenzenesulfonyl hydrazide (OBSH) foaming agents, thereby finding that the above object can be achieved, and the present invention is completed. It came to do.

That is, this invention relates to the following foam wallpaper and its manufacturing method .
1. A foam wallpaper having at least a foamed resin layer on a paper substrate,
(1) The foamed resin layer is formed by foaming a foaming agent-containing resin layer containing a thermally decomposable foaming agent,
(2) The foaming agent-containing resin layer contains an azodicarbonamide-based foaming agent and an oxybisbenzenesulfonylhydrazide-based foaming agent as a thermally decomposable foaming agent, and an ethylene-methacrylic acid copolymer as a resin component. Formed by extruding a resin composition containing,
(3) The foamed wallpaper, wherein the resin composition has a melt flow rate at 120 ° C. of 1.5 to 10 g / 10 min.
2. Item 2. The foamed wallpaper according to Item 1, wherein the blending ratio of the azodicarbonamide-based foaming agent and the oxybisbenzenesulfonylhydrazide-based foaming agent is 9.5: 0.5 to 1: 1 in order of weight ratio.
3. Item 3. The foamed wallpaper according to Item 1 or 2, wherein the ethylene-methacrylic acid copolymer has a methacrylic acid content of 15% by weight or less.
4). Item 4. The foamed wallpaper according to any one of Items 1 to 3, wherein a non-foamed resin layer A is further formed on the front surface of the foamed resin layer.
5). Item 5. The foamed wallpaper according to any one of Items 1 to 4, wherein a non-foamed resin layer B is further formed between the paper substrate and the foamed resin layer.
6). The foamed wallpaper according to any one of Items 1 to 5, wherein the resin component is crosslinked by electron beam irradiation.
7 . Item 7. The foamed wallpaper according to any one of Items 1 to 6 , wherein embossing is performed on the outermost surface layer of the foamed wallpaper.
8). A method for producing a foam wallpaper having at least a foam resin layer on a paper substrate,
On a paper base material, containing an azodicarbonamide-based foaming agent and an oxybisbenzenesulfonylhydrazide-based foaming agent as a pyrolytic foaming agent, and containing an ethylene-methacrylic acid copolymer as a resin component, 120 ° C. The resin composition having a melt flow rate of 1.5 to 10 g / 10 min is extruded to form a foaming agent-containing resin layer, and then the resulting foaming agent-containing resin layer is foamed by heat treatment. Forming a foamed resin layer.
9. Item 10. The method for producing a foam wallpaper according to Item 8, wherein the temperature during the extrusion film formation is 90 to 140 ° C.
10. Item 10. The foamed wallpaper according to Item 8 or 9, wherein the blending ratio of the azodicarbonamide-based blowing agent and the oxybisbenzenesulfonylhydrazide-based blowing agent is 9.5: 0.5 to 1: 1 in order of weight ratio. Manufacturing method.
11. Item 11. The method for producing a foam wallpaper according to any one of Items 8 to 10, wherein the ethylene-methacrylic acid copolymer has a methacrylic acid content of 15% by weight or less.
12 Item 12. The method for producing foamed wallpaper according to any one of Items 8 to 11, wherein the non-foamed resin layer A is further formed on the front surface of the foamed resin layer.
13. Item 13. The method for producing a foam wallpaper according to any one of Items 8 to 12, wherein the non-foamed resin layer B is further formed between the paper base and the foamed resin layer.
14 Item 14. The method for producing foamed wallpaper according to any one of Items 8 to 13, wherein the resin component is crosslinked by performing electron beam irradiation before the heat treatment.
15. Item 15. The method for producing foamed wallpaper according to any one of Items 8 to 14, wherein embossing is performed on the outermost surface layer of the foamed wallpaper.

1. Foam wallpaper The foam wallpaper of the present invention is a foam wallpaper having at least a foam resin layer on a paper substrate,
(1) The foamed resin layer is formed by foaming a foaming agent-containing resin layer containing a thermally decomposable foaming agent,
(2) The foaming agent-containing resin layer contains an azodicarbonamide (ADCA) -based foaming agent and an oxybisbenzenesulfonyl hydrazide (OBSH) -based foaming agent as a pyrolytic foaming agent, and an ethylene- Formed by extruding a resin composition containing a methacrylic acid copolymer (EMAA),
(3) The resin composition has a melt flow rate (MFR) at 120 ° C. of 1.5 to 10 g / 10 min.

  Since the MFR (120 ° C.) of the resin composition for extruding and forming the foaming agent-containing resin layer is 1.5 to 10 g / 10 minutes, the foamed wallpaper of the present invention having the above characteristics has a conventional extrusion temperature. Even if the temperature is lower than the conditions, the fluidity of the resin composition suitable for extrusion can be ensured. Thereby, since it becomes possible to use an OBSH foaming agent in addition to the ADCA foaming agent, yellowing due to the reaction between the ADCA foaming agent and EMAA can be effectively suppressed. That is, the foamed wallpaper of the present invention is suppressed in design deterioration due to yellowing and has good extrusion characteristics (productivity of foamed wallpaper).

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 between the paper-based substrate and the foamed resin layer can be obtained.

  As the non-foamed resin layer B, for example, ethylene-vinyl acetate copolymer (EVA) 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.

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

Foamed resin layer The foamed resin layer is formed by foaming a foaming agent-containing resin layer containing a thermally decomposable foaming agent. The foaming agent-containing resin layer is formed by extruding and forming a resin composition containing an ADCA foaming agent and an OBSH foaming agent as a thermal decomposition foaming agent and containing EMAA as a resin component. The

  The resin component contained in the resin composition may be substantially only EMAA, but other resin components may be added if necessary. By making the resin component substantially only EMAA, the surface strength of the foamed wallpaper can be increased. The methacrylic acid content (MAA content) of EMAA is not limited, but is preferably 15% by weight or less, and more preferably 10 to 15% by weight. By setting the MAA content low, it is easy to improve the scratch resistance of the foamed wallpaper.

  The pyrolytic foaming agent contains an ADCA foaming agent and an OBSH foaming agent. The content ratio of the two is not limited, but the total amount of both is 100% by weight and the content of the OBSH foaming agent is 5% by weight or more, so that the whiteness as white wallpaper can be secured. The occurrence of changes can be effectively suppressed. That is, it is preferable that ADCA foaming agent: OBSH foaming agent = 9.5: 0.5 to 1: 1 (weight ratio). More preferably, it is about 9: 1 to 3: 1 (weight ratio).

  The content of the pyrolytic foaming agent can be appropriately set according to a desired foaming 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 foaming agent is preferably about 1 to 20 parts by weight with respect to 100 parts by weight of the resin component.

  Various additives may be added to the resin composition. For example, inorganic fillers, pigments and cell regulators. In addition, stabilizers, lubricants, and the like can be used as additives.

  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.

  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 the inorganic filler include calcium carbonate, aluminum hydroxide, magnesium hydroxide, antimony trioxide, zinc borate, and a molybdenum compound. 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.

  As for the pigment, 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, zinc sulfide; for example, aniline black, perylene black, azo (azo lake, insoluble azo, condensed azo), many Cyclic (isoindolinone, isoindoline, quinophthalone, perinone, flavantron, anthrapyrimidine, anthraquinone, quinacridone, perylene, diketopyrrolopyrrole, dibromanthanthrone, dioxazine, thioindigo, phthalocyanine, indanthrone 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.

  The MFR (120 ° C.) of the resin composition is set to 1.5 to 10 g / 10 minutes. Preferably it sets to 1.5-5.0 g / 10min. By setting to such MFR, it is possible to ensure good fluidity of the resin composition at the time of extrusion film formation even at a lower temperature than before. The MFR of such a resin composition is adjusted, for example, by selecting the type of EMAA resin.

  In addition, MFR of this specification is the value measured by the test method of JISK7210 (flow test method of thermoplastics). The test condition is that the temperature of “190 ° C., 21.18N (2.16 kgf)” described in JIS K 6922 is 120 ° C.

  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
A non-foamed resin layer A may be further formed on the front surface of the foamed resin layer.

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 EMAA, ethylene-acrylic acid copolymer, and ionomer resin. As the ionomer resin, a resin having a structure in which EMAA and / or ethylene-acrylic acid copolymer molecules 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, abrasion 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%.

  The melt flow rate value of the resin component depends on the type of resin component used and the like, but generally may be set as appropriate within a range of 0.7 g / 10 min or more. Usually, it is preferably in the range of 0.7 to 10.0 g / 10 minutes, particularly 1.0 to 7.0 g / 10 minutes, and more preferably 2.0 to 5.0 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 In the present invention, a pattern pattern layer may be provided 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 A. 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)
In the present invention, a surface protective layer may be provided on the surface of the design pattern 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. 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 forming a surface protective layer for the purpose of surface strength (such as scratch resistance) of foamed wallpaper, stain resistance, protection of the pattern layer, etc., 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.

Embossing In this invention, you may attach | subject an embossing pattern suitably. In this case, embossing may be performed on the outermost surface layer (the side opposite to the paper-based substrate) of the foam wallpaper. 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.

2. The manufacturing method of foaming wallpaper The manufacturing method of foaming wallpaper is not specifically limited. For example, a foam wallpaper having a foamed resin layer and a non-foamed resin layer A on a paper-based substrate is heated after film formation by simultaneous melt extrusion of the foaming agent-containing resin layer and the non-foamed resin layer A on a paper-based substrate. Thus, the foaming agent-containing resin layer is obtained as a foamed resin layer.

  For simultaneous melt extrusion, a multi-manifold type T-die capable of simultaneously forming 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 this invention, since MFR (120 degreeC) of the resin composition for forming a foaming agent containing resin layer is set to 1.5-10 g / 10min, the fluidity | liquidity suitable for extrusion of the said resin composition Therefore, the heating temperature applied for achieving the above can be about 90 to 140 ° C, preferably about 100 to 120 ° C. For this reason, conventionally only ADCA foaming agents could be used substantially, but OBSH foaming agents can also be used in combination.

  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, and the like 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 MFR (120 ° C.) of the resin composition for extruding the foaming agent-containing resin layer is 1.5 to 10 g / 10 min, the foamed wallpaper of the present invention has a lower temperature than the conventional extrusion temperature conditions. Even so, the fluidity of the resin composition suitable for extrusion can be ensured. Thereby, since it becomes possible to use an OBSH foaming agent in addition to the ADCA foaming agent, yellowing due to the reaction between the ADCA foaming agent and EMAA can be effectively suppressed. That is, the foamed wallpaper of the present invention is suppressed in design deterioration due to yellowing and has good extrusion characteristics (productivity of foamed wallpaper).

  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
Using a three-type three-layer multi-manifold T-die extruder, the non-foamed resin layer A / foaming agent-containing resin layer / non-foamed resin layer B were extruded and formed on the backing paper in the order of thickness 10 μm / 100 μm / 10 μm. . Thereby, the laminated body which consists of non-foaming resin layer A / foaming agent containing resin layer / non-foaming resin layer B / backing paper was obtained.

  As the backing paper, “NI-65A (manufactured by Nippon Paper Industries Co., Ltd.)” was prepared, heated to 90 ° C., and then the above three layers were extruded to form a film.

  As for the extrusion conditions, the cylinder temperature containing the resin for forming the non-foamed resin layer A was 115 ° C., the cylinder temperature containing the resin composition for forming the foaming agent-containing resin layer was 110 ° C., and non-foamed The cylinder temperature in which the resin for forming the resin layer B was accommodated was 100 ° C. The die temperature was 110 ° C. for all.

  The laminate was irradiated with an electron beam (200 KV, 3 Mrad) from the non-foamed resin layer A side, and the foaming agent-containing resin layer and the non-foamed resin layer A were particularly resin-crosslinked. Further, a corona discharge treatment was performed on the non-foamed resin layer A.

Next, an EVA-based aqueous emulsion was applied on the non-foamed resin layer A (2 g / m ² ) to form a primer layer, and a fabric pattern was printed with an aqueous ink “Hydric” (manufactured by Dainichi Seika Kogyo). .

  Next, the laminate on which the fabric pattern was printed was heated in a gear oven (220 ° C. × 30 seconds) to foam the foaming agent-containing resin layer.

  Finally, a foamed wallpaper was obtained by embossing the fabric with a texture pattern.

  Each layer was formed using the following components.

  The non-foamed resin layer A was formed by EMAA “Nucleel N1560, manufactured by Mitsui DuPont Polychemical”.

  The foaming agent-containing resin layer consists of 80 parts by weight of EMAA “Nucrel N035C, Mitsui DuPont Polychemical”, 20 parts by weight of EMAA “Nucleel N1050H, Mitsui DuPont Polychemical”, calcium carbonate “Whiteon H, Toyo Fine Chemical” 40 parts by weight, titanium dioxide “Taypure R-108, manufactured by DuPont” 20 parts by weight, ADCA foaming agent “Vinhole AC # 3, manufactured by Eiwa Kasei Kogyo” 4.5 parts by weight, and OBSH foaming agent “Neocerbon N # 7000, Eiwa Chemicals It was formed from a resin composition consisting of 0.5 parts by weight of “Industry”. The MFR (120 ° C.) of the resin composition was 1.5 g / 10 minutes.

  The non-foamed resin layer B was formed by EVA “Evaflex EV150, manufactured by Mitsui DuPont Polychemical”.

Example 2
50 parts by weight of EMAA “Nucrel N1050H, made by Mitsui DuPont Polychemical”, 50 parts by weight of EMAA “Nucleel N1110H, made by Mitsui DuPont Polychemical”, calcium carbonate “Whiteon H, made by Toyo Fine Chemical” 40 parts by weight, titanium dioxide “Taypure R-108, manufactured by DuPont” 20 parts by weight, ADCA foaming agent “Vinhole AC # 3, manufactured by Eiwa Kasei Kogyo” 4.5 parts by weight, and OBSH foaming agent “Neocerbon N # 7000, Eiwa Chemicals It was formed from a resin composition consisting of 0.5 parts by weight of “Industry”. The MFR (120 ° C.) of the resin composition was 10 g / 10 minutes. Otherwise, a foamed wallpaper was obtained in the same manner as in Example 1.

Comparative Example 1
A foamed wallpaper was obtained in the same manner as in Example 1 except that no OBSH foaming agent was used. In addition, MFR (120 degreeC) of the resin composition for forming a foaming agent containing resin layer was 1.5.

Comparative Example 2
The foaming agent-containing resin layer is made of 100 parts by weight of EMAA “Nucleel N035C, made by Mitsui DuPont Polychemical”, 40 parts by weight of calcium carbonate “Whiteon H, made by Toyo Fine Chemical”, titanium dioxide “Taypure R-108, made by DuPont” 20 Part by weight, formed by a resin composition comprising 4.5 parts by weight of ADCA foaming agent “Vinole AC # 3, made by Eiwa Kasei Kogyo” and 0.5 parts by weight of OBSH foaming agent “Neocelbon N # 7000, made by Eiwa Kasei Kogyo” . The MFR (120 ° C.) of the resin composition was 1 g / 10 minutes. Otherwise, a foamed wallpaper was obtained in the same manner as in Example 1.

Comparative Example 3
The foaming agent-containing resin layer is made of 100 parts by weight of EMAA “Nucleel N1050H, made by Mitsui DuPont Polychemical”, 40 parts by weight of calcium carbonate “Whiteon H, made by Toyo Fine Chemical”, and titanium dioxide “Taypure R-108, made by DuPont” 20 Part by weight, formed by a resin composition comprising 4.5 parts by weight of ADCA foaming agent “Vinole AC # 3, made by Eiwa Kasei Kogyo” and 0.5 parts by weight of OBSH foaming agent “Neocelbon N # 7000, made by Eiwa Kasei Kogyo” . The MFR (120 ° C.) of the resin composition was 33.3 g / 10 minutes. Otherwise, a foamed wallpaper was obtained in the same manner as in Example 1.

Test example 1
Regarding the foamed wallpaper produced in the examples and comparative examples, 1) the whiteness of the foamed wallpaper, and 2) the film forming property at the time of production were evaluated. The results are shown in Table 1 below.

1) The whiteness of the foamed wallpaper was measured from the non-foamed resin layer A side using a spectrophotometer defined in JIS K5600-4-5. The color coordinates L ^* , a ^* , b ^* were determined, and the case where b ^* was 3.5 or more was evaluated as x, and the case where it was less than 3.5 was evaluated as ◯. In addition, if the whiteness of foaming wallpaper is less than 3.5, the loss of the design property by yellowing is suppressed.

  2) The film-forming property at the time of production is evaluated as ○ when there is no in-machine foaming (early foaming in the cylinder before extrusion film formation) and the film thickness is uniform, and does not satisfy any of the requirements. The case was rated as x.

Claims (15)

A foam wallpaper having at least a foamed resin layer on a paper substrate,
(1) The foamed resin layer is formed by foaming a foaming agent-containing resin layer containing a thermally decomposable foaming agent,
(2) The foaming agent-containing resin layer contains an azodicarbonamide-based foaming agent and an oxybisbenzenesulfonylhydrazide-based foaming agent as a thermally decomposable foaming agent, and an ethylene-methacrylic acid copolymer as a resin component. Formed by extruding a resin composition containing,
(3) The foamed wallpaper, wherein the resin composition has a melt flow rate at 120 ° C. of 1.5 to 10 g / 10 min.   The foamed wallpaper according to claim 1, wherein the blending ratio of the azodicarbonamide-based blowing agent and the oxybisbenzenesulfonylhydrazide-based blowing agent is 9.5: 0.5 to 1: 1 in order of weight ratio.   The foamed wallpaper according to claim 1 or 2, wherein the ethylene-methacrylic acid copolymer has a methacrylic acid content of 15% by weight or less.   The foamed wallpaper according to any one of claims 1 to 3, wherein a non-foamed resin layer A is further formed on the front surface of the foamed resin layer.   The foamed wallpaper according to any one of claims 1 to 4, wherein a non-foamed resin layer B 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 the resin component is crosslinked by electron beam irradiation. The foamed wallpaper according to any one of claims 1 to 6 , wherein embossing is performed on the outermost surface layer of the foamed wallpaper. A method for producing a foam wallpaper having at least a foam resin layer on a paper substrate,
On a paper base material, containing an azodicarbonamide-based foaming agent and an oxybisbenzenesulfonylhydrazide-based foaming agent as a pyrolytic foaming agent, and containing an ethylene-methacrylic acid copolymer as a resin component, 120 ° C. The resin composition having a melt flow rate of 1.5 to 10 g / 10 min is extruded to form a foaming agent-containing resin layer, and then the resulting foaming agent-containing resin layer is foamed by heat treatment. Forming a foamed resin layer. The method for producing a foam wallpaper according to claim 8, wherein a temperature at the time of the extrusion film formation is 90 to 140 ° C. The foamed wallpaper according to claim 8 or 9, wherein a blending ratio of the azodicarbonamide-based blowing agent and the oxybisbenzenesulfonylhydrazide-based blowing agent is 9.5: 0.5 to 1: 1 in order of weight ratio. Manufacturing method. The method for producing a foam wallpaper according to any one of claims 8 to 10, wherein the ethylene-methacrylic acid copolymer has a methacrylic acid content of 15% by weight or less. The method for producing a foamed wallpaper according to any one of claims 8 to 11, wherein a non-foamed resin layer A is further formed on the front surface of the foamed resin layer. The method for producing a foam wallpaper according to any one of claims 8 to 12, wherein a non-foamed resin layer B is further formed between the paper-based substrate and the foamed resin layer. The method for producing a foam wallpaper according to any one of claims 8 to 13, wherein the resin component is crosslinked by performing electron beam irradiation before the heat treatment. The method for producing a foam wallpaper according to any one of claims 8 to 14, wherein embossing is performed on the outermost surface layer of the foam wallpaper.