JP5725696B2 - Foam wallpaper - Google Patents

Description

  The present invention relates to a foamed wallpaper in which discoloration with time (weather resistance discoloration) of a foamed resin layer after foaming is suppressed.

  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.).

  As a layer structure of the foam wallpaper, a laminate of a non-foam resin layer on the front surface of the foam resin layer is known. Such a foam wallpaper is produced by, for example, laminating a foaming agent-containing resin layer and a non-foaming resin layer on a paper base by simultaneous melt extrusion, and then foaming the foaming agent-containing resin layer.

  Foamed wallpaper requires surface strength (especially scratch resistance). Therefore, as a non-foamed resin layer, it is known that an ethylene-methacrylic acid copolymer (EMAA) advantageous for surface strength is used as a resin component.

  However, this non-foamed resin layer has a problem of causing a reaction between methacrylic acid as a resin component and metal ions in the foamed resin layer. As a result, there is a problem that the foamed resin layer after foaming tends to discolor over time.

  Accordingly, development of a foamed wallpaper in which discoloration with time of the foamed resin layer after foaming is suppressed 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 containing a thermally decomposable foaming agent, and further foaming the foaming agent-containing resin layer to form a foaming resin layer. Provided is a foamed wallpaper in which discoloration of the foamed resin layer is suppressed over time.

  As a result of intensive research, the inventor of the present invention has the above object when a non-foamed resin layer is formed by a resin composition containing a specific compound in the foamed resin layer and further containing a specific resin component. The present invention has been completed.

1. A foam wallpaper having at least a foamed resin layer and a non-foamed resin layer A on a paper-based 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 is formed of a resin composition containing a resin component, a zinc-based foaming aid and pentaerythritol,
(3) The resin component contained in the foaming agent-containing resin layer is polyethylene, polypropylene, polystyrene, ethylene-vinyl acetate copolymer resin, acrylonitrile-butadiene-styrene copolymer, acrylonitrile-styrene copolymer, nylon, It is at least one selected from the group consisting of polyacetal resins, polycarbonate resins, polyester resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyurethane resins and polyvinyl chloride resins,
(4) The non-foamed resin layer A is made of polyethylene and a copolymer of ethylene and an α-olefin having 4 or more carbon atoms (linear low density polyethylene) on the front surface of the foaming agent-containing resin layer. A foam wallpaper which is formed of a resin composition containing at least one selected from the group as a resin component.
2 . Item 2. The foamed wallpaper according to Item 1 , wherein the resin composition constituting the foaming agent-containing resin layer contains 0.01 to 10 parts by weight of the pentaerythritol with respect to 100 parts by weight of the resin component.
3 . Item 3. The foamed wallpaper according to Item 1 or 2 , wherein the resin composition constituting the foaming agent-containing resin layer contains an azodicarbonamide-based foaming agent as the thermally decomposable foaming agent.
4 . Item 4. The foamed wallpaper according to any one of Items 1 to 3 , wherein a non-foamed resin layer B is further formed between the paper substrate and the foamed resin layer.
5 . Item 5. The foamed wallpaper according to any one of Items 1 to 4 , which is embossed from the top surface layer of the foamed wallpaper.
6 . A foamed laminate of foamed wallpaper having at least a foaming agent-containing resin layer and a non-foamed resin layer A on a paper-based substrate,
(1) The foaming agent-containing resin layer is formed of a resin composition containing a pyrolytic foaming agent, a resin component, a zinc-based foaming aid and pentaerythritol,
(2) The resin component contained in the foaming agent-containing resin layer is polyethylene, polypropylene, polystyrene, ethylene-vinyl acetate copolymer resin, acrylonitrile-butadiene-styrene copolymer, acrylonitrile-styrene copolymer, nylon, It is at least one selected from the group consisting of polyacetal resins, polycarbonate resins, polyester resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyurethane resins and polyvinyl chloride resins,
(3) The non-foamed resin layer A is made of polyethylene and a copolymer of ethylene and an α-olefin having 4 or more carbon atoms (linear low density polyethylene) on the front surface of the foaming agent-containing resin layer. A laminate before foaming of foamed wallpaper, characterized in that it is formed of a resin composition containing at least one selected from the group as a resin component.
7 . The resin composition constituting the foaming agent-containing resin layer contains 0.01 to 10 parts by weight of the pentaerythritol with respect to 100 parts by weight of the resin component, and is a laminate before foaming of foamed wallpaper according to the above item 6. body.

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

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 is formed by forming a resin composition containing pentaerythritol,
(3) A non-foamed resin layer A made of an ethylene-based polymer or copolymer having no methacrylic acid as a copolymer component is further formed on the front surface of the foamed resin layer.

  The foamed wallpaper of the present invention having the above characteristics uses pentaerythritol as an additive in the foamed resin layer. Moreover, the foamed wallpaper of this invention makes the layer formed of the resin composition which contains the ethylene-type polymer or copolymer which does not have methacrylic acid as a copolymer component as a resin component as a non-foamed resin layer. For this reason, the foamed wallpaper of the present invention suppresses the time-dependent discoloration (weather resistance discoloration) of the foamed resin layer after foaming.

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 5 to 50 μm, more preferably about 8 to 20 μm.

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

  The foaming agent-containing resin layer is not limited as long as it is foamed by the action of the foaming agent (for example, foamed when heated), but polyethylene, polypropylene, polystyrene, ethylene-vinyl acetate copolymer resin (EVA). , Acrylonitrile-butadiene-styrene copolymer (ABS resin), acrylonitrile-styrene copolymer, nylon, polyacetal resin, polycarbonate resin, polyester resin, polyvinyl acetate resin, polyvinyl alcohol resin, polyurethane resin And thermoplastic resins such as polyvinyl chloride resins, copolymers, and mixed resins thereof. Among these, from the viewpoint of environmental protection, polyolefin resins are preferable, and ethylene-vinyl acetate copolymer resin (EVA) is particularly preferable. For example, a resin composition containing an EVA resin, an inorganic filler, a pigment, a pyrolytic foaming agent and a foaming aid can be suitably used. In addition, stabilizers, lubricants and the like can be used as additives.

  When EVA resin is used as the resin component, the vinyl acetate content (copolymerization ratio) of the EVA resin is not limited, but is preferably about 5 to 30% by weight, more preferably about 10 to 20% by weight. .

  The melt flow rate value (MFR) of the resin component is not particularly limited, but is preferably about 5 to 75 g / 10 minutes, and more preferably about 10 to 30 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 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.

  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. .

  In the present invention, the foamed resin layer contains pentaerythritol. By containing pentaerythritol, it is possible to provide a foamed wallpaper in which yellowing discoloration of the foamed resin layer after foaming is reduced and discoloration with time is suppressed. The content of pentaerythritol is preferably 0.01 to 10 parts by weight and more preferably 0.05 to 3 parts by weight with respect to 100 parts by weight of the resin component contained in the resin composition.

  As the foaming aid, it is preferable to use a zinc-based foaming aid. The zinc-based foaming aid contributes to the lowering of the foaming temperature of the ADCA-based foaming agent and can significantly reduce the foaming temperature. This contributes to improving the productivity of foam wallpaper. Although content of a foaming adjuvant is not limited, about 1-10 weight part is preferable with respect to 100 weight part of resin components, and about 3-8 weight part is more preferable.

  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.

  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 is 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 non-foamed resin layer is a layer formed of a resin composition containing, as a resin component, an ethylene polymer or copolymer that does not have methacrylic acid as a copolymer component. Since the non-foamed resin layer does not contain methacrylic acid as a copolymer component, it does not react with the metal ions in the foamed resin layer. Therefore, it is possible to provide a foamed wallpaper in which discoloration with time of the foamed resin layer after foaming is suppressed.

Examples of the resin component include polyethylene, copolymers of ethylene and carbon atoms and 4 or more α-olefins (linear low density polyethylene), ethylene - vinyl acetate copolymer (EVA), ethylene - vinyl acetate copolymer Weight At least one selected from the group consisting of a combined saponified product or ionomer can be suitably used as the resin component. In particular, a polyethylene polymer is preferable. 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 5 to 50 μm, more preferably about 8 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%.

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 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 foaming agent. The heating temperature is about 200 to 220 ° C., and the heating time is about 30 to 45 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.

  The foamed wallpaper of the present invention uses pentaerythritol as an additive in the foamed resin layer. Moreover, the foamed wallpaper of this invention makes the layer formed of the resin composition which contains the ethylene-type polymer or copolymer which does not have methacrylic acid as a copolymer component as a resin component as a non-foamed resin layer. For this reason, the foamed wallpaper of the present invention suppresses the time-dependent discoloration (weather resistance discoloration) of the foamed resin layer after foaming.

It is a schematic diagram which illustrates the layer structure of the foam wallpaper of this invention.

  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 / 60 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, “WK-665DO (manufactured by Kojin)” 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, 30 kGy) 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. Furthermore, a texture pattern was printed with water-based 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. × 35 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 of a polyethylene resin “Petrocene 350, manufactured by Tosoh Corporation”.

  The foaming agent-containing resin layer is made of 100 parts by weight of EVA resin “V406, made by Mitsui DuPont Polychemical”, 30 parts by weight of titanium dioxide “CR63, made by Ishihara Sangyo”, 6 parts by weight of ADCA foaming agent “AZ3050I, made by Otsuka Chemical”, It was formed with a resin composition comprising 5.3 parts by weight of a foaming aid “MFX50J-3, manufactured by Daikyo Kasei” and 0.4 parts by weight of pentaerythritol.

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

Example 2
A foamed wallpaper was obtained in the same manner as in Example 1 except that the non-foamed resin layer was changed to polyethylene resin “Petrocene 349, manufactured by Tosoh Corporation”.

Comparative Example 1
A foamed wallpaper was obtained in the same manner as in Example 1 except that the non-foamed resin layer was changed to EMAA resin “N1035, manufactured by Mitsui DuPont Polychemical”.

Comparative Example 2
A foamed wallpaper was obtained in the same manner as in Example 1 except that the non-foamed resin layer was EMAA resin “N1035, manufactured by Mitsui DuPont Polychemical”, and pentaerythritol was not used for the foaming agent-containing resin layer.

Comparative Example 3
A foamed wallpaper was obtained in the same manner as in Example 1 except that the non-foamed resin layer was a polyethylene resin “Petrocene 349, manufactured by Tosoh Corporation”, and pentaerythritol was not used in the foaming agent-containing resin layer.

Test example 1
Regarding foamed wallpaper produced in Examples and Comparative Examples, 1) yellow discoloration of the foam decorative sheet, and 2) weather resistance discoloration of the foam decorative sheet were evaluated. The results are shown in Table 1 below.

  1) Yellowing discoloration of the foamed decorative sheet was evaluated according to the following criteria. That is, the color of the foamed resin layer was measured with a color measuring device “Color Difference Meter CR-300, manufactured by Konica Minolta”.

  2) Weather resistance discoloration was evaluated according to the following criteria. First, an acceleration test (40 hours) was performed using a fade meter “ultraviolet fade meter U48AU, manufactured by Suga Test Instruments”. Next, the degree of discoloration of the foamed resin layer was measured by a colorimetric device “color difference meter CR-300, manufactured by Konica Minolta”. When the degree of color change (ΔE) was ΔE ≦ 1.9, the evaluation was ○, and when ΔE> 1.9, the evaluation was ×.

表１から明らかなように、発泡含有樹脂層中にペンタエリスリトールが存在し、非発泡樹脂層Ａにメタクリル酸を含有しないポリエチレンを用いるとｂ値が低減、すなわち発泡後の黄変色が低減され、耐候性を向上できる（実施例１あるいは２と比較例２あるいは３の比較）。

As is apparent from Table 1, pentaerythritol is present in the foam-containing resin layer, and b value is reduced when polyethylene not containing methacrylic acid is used in the non-foamed resin layer A, that is, yellowing after foaming is reduced, The weather resistance can be improved (comparison between Example 1 or 2 and Comparative Example 2 or 3).

  This is because pentaerythritol, which is an additive component of the foaming auxiliary agent, reduces the b value, that is, yellowing discoloration after foaming is reduced, and is effective in suppressing discoloration over time, and does not contain methacrylic acid in the non-foamed layer This is because since polyethylene is used, reaction with metal ions does not occur, yellow discoloration is reduced, and color change with time is more effectively suppressed.

  In general, as the b value after foaming is low, that is, the material that hardly yellows after foaming is less likely to change with time. However, the suppression of the change with time is insufficient only by adding pentaerythritol to the foam-containing resin layer (comparison between Example 1 or 2 and Comparative Example 1). Similarly, it is not sufficient to use polyethylene that does not contain methacrylic acid for the non-foamed resin layer A (comparison between Example 2 and Comparative Example 3). Accordingly, weather resistance can be improved by adding pentaerythritol to the foamed layer and using polyethylene not containing methacrylic acid in the non-foamed layer.

1. Backing paper2. Non-foamed resin layer B
3. 3. Foamed resin layer Non-foamed resin layer A
5). Pattern layer

Claims (7)

A foam wallpaper having at least a foamed resin layer and a non-foamed resin layer A on a paper-based 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 is formed of a resin composition containing a resin component, a zinc-based foaming aid and pentaerythritol,
(3) The resin component contained in the foaming agent-containing resin layer is polyethylene, polypropylene, polystyrene, ethylene-vinyl acetate copolymer resin, acrylonitrile-butadiene-styrene copolymer, acrylonitrile-styrene copolymer, nylon, It is at least one selected from the group consisting of polyacetal resins, polycarbonate resins, polyester resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyurethane resins and polyvinyl chloride resins,
(4) The non-foamed resin layer A is made of polyethylene and a copolymer of ethylene and an α-olefin having 4 or more carbon atoms (linear low density polyethylene) on the front surface of the foaming agent-containing resin layer. A foam wallpaper which is formed of a resin composition containing at least one selected from the group as a resin component. The foamed wallpaper of Claim 1 in which the resin composition which comprises the said foaming agent containing resin layer contains 0.01-10 weight part of said pentaerythritol with respect to 100 weight part of resin components. The foamed wallpaper according to claim 1 or 2 , wherein the resin composition constituting the foaming agent-containing resin layer contains an azodicarbonamide-based foaming agent as the pyrolytic foaming agent. The foamed wallpaper according to any one of claims 1 to 3 , 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 4 , which is embossed from above the outermost surface layer of the foamed wallpaper. A foamed laminate of foamed wallpaper having at least a foaming agent-containing resin layer and a non-foamed resin layer A on a paper-based substrate,
(1) The foaming agent-containing resin layer is formed of a resin composition containing a pyrolytic foaming agent, a resin component, a zinc-based foaming aid and pentaerythritol,
(2) The resin component contained in the foaming agent-containing resin layer is polyethylene, polypropylene, polystyrene, ethylene-vinyl acetate copolymer resin, acrylonitrile-butadiene-styrene copolymer, acrylonitrile-styrene copolymer, nylon, It is at least one selected from the group consisting of polyacetal resins, polycarbonate resins, polyester resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyurethane resins and polyvinyl chloride resins,
(3) The non-foamed resin layer A is made of polyethylene and a copolymer of ethylene and an α-olefin having 4 or more carbon atoms (linear low density polyethylene) on the front surface of the foaming agent-containing resin layer. A laminate before foaming of foamed wallpaper, characterized in that it is formed of a resin composition containing at least one selected from the group as a resin component. The laminate before foaming of foamed wallpaper according to claim 6 , wherein the resin composition constituting the foaming agent-containing resin layer contains 0.01 to 10 parts by weight of the pentaerythritol with respect to 100 parts by weight of a resin component. body.

Images