JP2018051960A - Foam wall paper and manufacturing method of foam wall paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a foam wall paper having high surface strength and necessary thickness, saved weight and high suitability to dense color printing without generating whitening.SOLUTION: A foam wall paper 10 is manufactured by layering a paper base material 1, a foam resin layer 2 formed by a resin composition containing an aqueous emulsion resin, a foaming agent and an inorganic filler, a picture pattern printed layer 3 having a picture pattern by printing, and a surface protective layer 4 containing a resin and a filler in this order, same embossment pattern 5 is formed on the foam resin layer 2, the picture pattern printed layer 3 and the surface protective layer 4, the resin composition forming the foam resin layer 2 contains the inorganic filler in a range of 50 pts.mass to 150 pts.mass and the foaming agent in a range of 1 pts.mass to 20 pts.mass based on 100 pts.mass of the aqueous emulsion resin and basis weight of the resin composition is in a range of 50 g/mto 150 g/m.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a foam wallpaper and a method for producing a foam wallpaper.

  Foaming is performed by cross-linking the foaming agent-containing resin layer of a laminated sheet (so-called foamed wallpaper raw material) in which a foaming agent-containing resin layer is laminated on a paper substrate (so-called wallpaper backing paper). A foam wallpaper having a resin layer can be produced. As an example of such foamed wallpaper, Patent Document 1 discloses a foamed wallpaper having a paper base material, a resin layer, and a pattern printing layer, and improving the adhesion and surface rubbing characteristics of the pattern printing layer.

JP 2007-196590 A

In many cases, the wallpaper is thickened with a foaming agent in order to conceal the unevenness of the foundation to be constructed. However, when the wallpaper is thickened using a foaming agent, the surface strength of the wallpaper is lowered, and the risk of breakage in the life during construction or after construction may increase.
As a means to thicken the wallpaper without using a foaming agent, there is a means to increase the basis weight of the resin layer provided in the wallpaper, but due to changes in the environment of the construction industry in recent years, heavy wallpaper that has a heavy transportation and construction load is There is a growing tendency to be shunned.
In addition, an increase in the amount of the foaming agent may cause many irregularities on the surface of the wallpaper, causing a load on the pattern printing layer provided on the wallpaper and causing cracks, resulting in a decrease in printing density and whitening. For this reason, the increase in the amount of the foaming agent is a significant hindrance factor especially in the printing of a dark color pattern, and there is a problem that the design is limited.
The present invention has been made in view of the above circumstances, and provides a foamed wallpaper having a high surface strength and a necessary and sufficient thickness while being light in weight and having high suitability for dark color printing without causing whitening, and a method for producing the same. The purpose is to provide.

In order to solve the above-mentioned problems, a foamed wallpaper according to one embodiment of the present invention is a foamed resin formed of a resin composition containing a paper base material, an aqueous emulsion resin, a foaming agent, and an inorganic filler. A layer, a pattern printing layer having a pattern by printing, a surface protective layer containing a resin and a filler are laminated in this order, and the same is applied to the foamed resin layer, the pattern printing layer, and the surface protective layer. An embossed pattern is formed, and the resin composition has an inorganic filler in the range of 50 to 150 parts by mass and a foaming agent in the range of 1 to 20 parts by mass with respect to 100 parts by mass of the aqueous emulsion resin. The basis weight of the resin composition is in the range of 50 g / m ² or more and 150 g / m ² or less.

Moreover, the manufacturing method of the foam wallpaper which concerns on 1 aspect of this invention contains an inorganic filler in the range of 50 to 150 mass parts with respect to 100 mass parts of aqueous | water-based emulsion resin on a paper base material, A foaming agent-containing resin layer is formed by applying a paste containing a foaming agent in the range of 1 part by mass or more and 20 parts by mass or less so that the basis weight is in the range of 50 g / m ² or more and 150 g / m ² or less. An embossing heater comprising a step, a step of printing a pattern printing layer having a pattern on the foaming agent-containing resin layer, a step of forming a surface protective layer on the pattern printing layer, and a laminate including the layers. In the step of heating the laminated body, the paper surface temperature of the laminated body at the outlet of the emboss heater is in the range of 160 ° C. or higher and 200 ° C. or lower, and the temperature range Within the foam The foaming agent contained in the contained resin layer is heated and foamed to form a foamed resin layer. Immediately after passing through the emboss heater, the laminate is added within the range of 9800 N / m to 24500 N / m with an embossing roll. The embossed pattern is imparted to the foamed resin layer, the pattern printing layer, and the surface protective layer.

  According to one aspect of the present invention, since the surface protective layer covers the pattern printing layer and the foamed resin layer, the surface is lightened while having high surface strength and necessary and sufficient thickness, and further to dark color printing without causing whitening. It is possible to provide a foam wallpaper having high suitability and a method for producing the same.

It is typical sectional drawing which shows an example of the shape of the cross section of the foam wallpaper based on embodiment of this invention.

<Embodiment>
Hereinafter, with reference to the drawings, a foam wallpaper and a method for manufacturing the same according to an embodiment of the present invention will be described. Here, the drawings are schematic, and the relationship between the thickness and the planar dimensions, the ratio of the thickness of each layer, and the like are different from the actual ones. Further, the embodiment described below exemplifies a configuration for embodying the technical idea of the present invention, and the technical idea of the present invention is that the material, shape, structure, etc. of the component parts are as follows. It is not something specific. The technical idea of the present invention can be variously modified within the technical scope defined by the claims described in the claims.

(Foam wallpaper)
In FIG. 1, an example of the cross-sectional shape of the foam wallpaper 10 which concerns on embodiment of this invention is shown.
In the foam wallpaper 10 according to the present embodiment, a foamed resin layer 2, a pattern printing layer 3, and a surface protective layer 4 are laminated in this order on a paper base material 1 serving as a base material. Furthermore, the embossed pattern 5 is formed on the surface of the foam wallpaper 10 according to the present embodiment.

[Paper base]
The paper substrate 1 is a so-called wallpaper backing paper (fibrous sheet). Examples of the paper base 1 include general paper for wallpaper (pulp-based sheets sized with a known sizing agent); flame-retardant paper (pulp-based sheets such as guanidine sulfamate and guanidine phosphate) Inorganic paper containing inorganic additives such as aluminum hydroxide and magnesium hydroxide; fine paper; thin paper; fiber mixed paper (paper made by mixing pulp and synthetic fiber) .
In the present embodiment, plain paper can be used as the paper substrate 1, and the basis weight is 50 / m ^{2 to} 100 g / m ² and the thickness is in the range of 80 μm to 150 μm. The rigidity required as a material is ensured.

[Foamed resin layer]
The foaming agent-containing resin layer (not shown) is formed by coating a resin (paste, resin composition) containing a foaming agent on the surface of the paper substrate 1. In the present embodiment, a foaming agent, a plasticizer, a stabilizer, a thinning agent, other organic additives, and an inorganic powder (inorganic filler) as a filler are appropriately mixed with the resin according to the intended use. A foaming agent-containing resin layer is provided on the surface of the substrate 1 by coating it in the form of a sheet or a pattern.
Examples of the resin coating method include a knife coating method, a nozzle coating method, a die coating method, a lip coating method, a comma coating method, a gravure coating method, a rotary screen coating method, and a reverse roll coating method. .
In addition, after applying a foaming agent containing resin layer to the paper base material 1, the foaming resin layer 2 is formed by heat-foaming the foaming agent contained in the foaming agent containing resin layer. When the foaming agent described above is heated and foamed, a laminate including at least the paper substrate 1 and the foaming agent-containing resin layer may be passed through the embossed heater.

As the resin contained in the foamed resin layer 2, a resin that can be used in the form of an aqueous emulsion, for example, a polyolefin-based resin can be used. In particular, at least an ethylene copolymer having ethylene and a component other than ethylene as a monomer is used. One type is more preferable.
Moreover, from the viewpoint of imparting fireproof performance, the total basis weight of the wallpaper is desirably 200 g / m ² or less.

  The ethylene copolymer is suitable for extrusion film formation from the viewpoint of the melting point and MFR. Examples of the ethylene copolymer include ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate copolymer ( EMA), ethylene-methacrylic acid copolymer (EMAA), ethylene-α olefin copolymer, and the like. These ethylene copolymers can be used alone or in admixture of two or more. Among these ethylene copolymers, at least one of ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer and ethylene-methacrylic acid copolymer is preferable, and when these are used in combination with other resins. The content of at least one of ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer and ethylene-methacrylic acid copolymer is preferably 70% by mass or more, and more preferably 80% by mass or more. Of the ethylene-vinyl acetate copolymer, ethylene-methyl methacrylate copolymer, and ethylene-methacrylic acid copolymer, an ethylene-vinyl acetate copolymer can be suitably used.

  Moreover, as content of monomers other than ethylene contained in an ethylene copolymer, 5 to 25 mass% is preferable, for example, and 9 to 20 mass% is more preferable. By adopting such a copolymerization ratio, the extrusion film forming property is further enhanced. As a specific example, the ethylene-vinyl acetate copolymer has a vinyl acetate copolymerization ratio (VA amount) of preferably 9% by mass to 25% by mass, and more preferably 9% by mass to 20% by mass. The ethylene-methyl methacrylate copolymer has a methyl methacrylate copolymerization ratio (MMA amount) of preferably 5% by mass to 25% by mass, and more preferably 5% by mass to 15% by mass. The ethylene-methacrylic acid copolymer has an acrylic acid copolymerization ratio (MAA amount) of preferably 2% by mass or more and 15% by mass or less, and more preferably 5% by mass or more and 11% by mass or less.

  Here, the resin contained in the foamed resin layer 2 is, for example, an MFR (melt flow rate) measured at 190 ° C. and a load of 21.18 N described in JIS K 6922 of 10 g or more and 10 g or less (10 g) per 10 minutes. / 10 minutes or more and 100 g / 10 minutes or less). When the MFR is within the above range, since the temperature rise when forming the foaming agent-containing resin layer by extrusion film formation is small and the film can be formed in a non-foamed state, when the pattern printing layer 3 is formed later, Print processing can be performed on a smooth surface and there are few pattern omissions. If the MFR is too large, the resin is too soft, and the resulting foaming agent-containing resin layer may have insufficient scratch resistance.

In addition, as the foaming agent contained in the foaming agent-containing resin layer, a foaming agent that is commonly used for foamed wallpaper can be used, and in particular, a thermally expandable microcapsule foaming agent has performance (foaming ratio). , Strength). In addition, azo, hydrazide, nitroso, etc. can be used.
The amount of the foaming agent added depends on the thickness of the foamed resin layer 2 (foaming agent-containing resin layer) and the foaming ratio (volume expansion coefficient before and after foaming), for example, 1 mass per 100 parts by mass of the resin. Part to 20 parts by mass, preferably about 5 parts to 15 parts by mass.
In addition, by setting the basis weight and foaming ratio of the foamed resin layer 2 (foaming agent-containing resin layer) to a foaming ratio of 50 g / m ^{2 to} 150 g / m ² and 4 times or more, a non-land concealing property can be obtained. In addition to having a sufficient volume to obtain and excellent surface strength, it is possible to sharply reproduce the uneven shape of the surface by embossing described later.

Examples of the inorganic powder contained in the foamed resin layer 2 include calcium carbonate, aluminum hydroxide, magnesium hydroxide, silica sand, talc, silicas, magnesium silicate, zinc borate, and titanium dioxide. The inorganic powder is added in an amount of 50 to 150 parts by mass with respect to 100 parts by mass of the resin.
Thus, the foamed resin layer 2 (foaming agent-containing resin layer) according to this embodiment is formed of a resin composition containing an aqueous emulsion resin, a foaming agent, and an inorganic filler.

[Picture printing layer 3]
The pattern print layer 3 imparts design properties to the foamed wallpaper 10. The pattern print layer 3 can be formed, for example, by printing a pattern on the surface of the foamed resin layer 2 (foaming agent-containing resin layer). The thickness of the pattern print layer 3 is different from the type of the pattern, but is generally preferably about 0.1 μm to 10 μm.
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 purpose.

  In the present embodiment, the pattern printing layer 3 uses a printing ink (non-foaming ink) and / or a foaming ink whose main component is an aqueous emulsion resin, a foaming ink whose main component is a vinyl chloride paste resin, or the like. Then, it is formed by a gravure printing method, a screen printing method, a flexographic printing method, an ink jet printing method, or the like. In addition to the printing ink, for example, a printing ink containing a colorant, a binder resin, and a solvent can be used. These inks may be known or commercially available.

As the colorant, for example, a pigment can be appropriately used. The pigment includes an inorganic pigment and an organic pigment. Inorganic pigments include, 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), and cadmium. Examples thereof include red, ultramarine blue, bitumen, cobalt blue, chromium oxide, cobalt green, aluminum powder, bronze powder, titanium mica, and zinc sulfide. Examples of the organic pigment include aniline black, perylene black, azo (azo lake, insoluble azo, condensed azo), polycyclic (isoindolinone, isoindoline, quinophthalone, perinone, flavantron, anthrapyrimidine, anthraquinone, Quinacridone, perylene, diketopyrrolopyrrole, dibromoanthanthrone, dioxazine, thioindigo, phthalocyanine, indanthrone, halogenated phthalocyanine). The content of the colorant is preferably about 10 to 50 parts by mass, more preferably about 15 to 30 parts by mass with respect to 100 parts by mass of the resin.
Further, when the foamed resin layer 2 serves as a solid layer for the pattern print layer 3 or when the foamed resin layer 2 is applied in a pattern pattern, the foamed resin layer 2 may also contain a colorant. good.

  Binder resin can be set according to the kind of lower layer resin which forms the pattern printing layer 3. FIG. Examples of the binder resin include acrylic resin, styrene resin, polyester resin, urethane resin, chlorinated polyolefin resin, vinyl chloride-vinyl acetate copolymer resin, polyvinyl butyral resin, alkyd resin, petroleum Resin, ketone resin, epoxy resin, melamine resin, fluorine resin, silicone resin, fiber derivative, rubber resin and the like.

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

In addition, when the pattern printing layer 3 is not formed on the foamed resin layer 2 (foaming agent-containing resin layer), an undercoat layer (primer layer) may be formed as an alternative to the pattern printing layer 3. The undercoat layer includes a polyolefin resin, an acrylic resin, a polyvinyl alcohol resin, and the like, and the basis weight after drying is preferably in the range of 1 g / m ² or more and 3 g / m ² or less.

[Surface protective layer]
The surface protective layer 4 is formed on the surface of the pattern printing layer 3 with the intention of adjusting the gloss and / or protecting the pattern printing layer 3. The thickness of the surface protective layer 4 is not limited, but is preferably about 0.1 μm to 15 μm. Here, the kind of the surface protective layer 4 is not limited. If it is the surface protective layer 4 aiming at gloss adjustment, there exists the surface protective layer 4 containing known fillers, such as a silica, for example. As a method for forming the surface protective layer 4, for example, a known method such as gravure printing can be employed. In addition, when the adhesiveness of the pattern printing layer 3 and the surface protection layer 4 is not fully acquired, the surface protection layer 4 can also be provided after carrying out the adhesion process (primer process) of the surface of the pattern printing layer 3 easily. . When the surface protective layer 4 is formed for the purpose of surface strength (scratch resistance, etc.), contamination resistance, protection of the picture printing layer 3 and the like of the foam wallpaper 10, the one containing an ionizing radiation curable resin as a resin. Is preferred. As the ionizing radiation curable resin, for example, those that undergo radical polymerization (curing) by electron beam irradiation are preferable.

In the present embodiment, the surface protective layer 4 is formed on the pattern printing layer 3, and a layer mainly composed of an aqueous emulsion resin is formed by a gravure printing method, a knife coating method, a nozzle coating method, a die coating method, It is formed by a lip coat method, a comma coat method or the like.
Examples of the resin contained in the surface protective layer 4 include polyolefin resins, acrylic resins, polyvinyl alcohol resins, fluorine resins, and the like, and acrylic resins are particularly preferable. These resins may be used alone or in combination of two or more. Moreover, when using resin which can be bridge | crosslinked for formation of the surface protective layer 4, you may perform a crosslinking process to the said resin as needed. The basis weight after drying of the surface protective layer 4 is preferably 10 g / m ² or more and 40 g / m ² or less, preferably 15 g / m ² or more and 30 g / m ² or less.

Further, a filler is added to the resin contained in the surface protective layer 4 as a matting agent (gloss adjusting agent). As the matting agent, for example, silica particles, alumina (α-alumina, etc.), inorganic particles such as calcium carbonate, barium sulfate, kaolinite, aluminosilicate, or organic particles such as polycarbonate, nylon, urethane resin are used. be able to.
Thus, the surface protective layer 4 according to the present embodiment contains an acrylic resin and a filler.

[Emboss]
The surface of the surface protective layer 4 that is the outermost layer of the foam wallpaper 10 is embossed (unevenness forming using an embossed plate), and the uneven shape is formed (given). Thus, the embossed pattern 5 is formed. In embossing, for example, the foam wallpaper 10 is passed between an emboss roll having a recess having a depth of 15 μm or more and a rubber back roll having a hardness of 50 degrees or more and less than 90 degrees to form an uneven shape on the foam wallpaper 10. You may make it give. As a method for measuring hardness, for example, JIS K-6301 A type can be used. Examples of the concavo-convex shape include a wood grain plate conduit groove, a stone plate surface unevenness, a cloth surface texture, a satin finish, a grain, a hairline, and a multiline groove.

In addition, as a method of forming an uneven shape (embossed pattern 5) on the surface of the surface protective layer 4, there are other methods such as a method of partially foaming with a foam suppression ink, or a chemical of partially heating and foaming with hot air or infrared rays. Although there is an embossing method, mechanical embossing by pressure welding with an embossing roll is particularly preferable because sharp unevenness can be obtained with respect to the foamed resin layer 2 and the like. In the present embodiment, in order to enhance the gas retention of the surface protective layer 4, the embossing pressure is desirably 9800 N / m or more and 24500 N / m or less, preferably 14700 N / m or more and 19600 N / m or less. . By setting the pressure within the range, the surface strength can be further increased.
Moreover, it is desirable to maintain the surface temperature of the foamed wallpaper 10 immediately before the contact of the embossed plate in the embossing process at 160 ° C. or higher and 200 ° C. or lower, preferably 170 ° C. or higher and 180 ° C. or lower.

(Effect of this embodiment)
(1) A foamed wallpaper 10 according to the present embodiment has a foamed resin layer 2 made of a resin composition containing an aqueous emulsion resin, a foaming agent, and an inorganic filler on a paper substrate 1, and a pattern by printing. The pattern print layer 3 and the surface protective layer 4 containing a resin and a filler are laminated. And the same uneven | corrugated shape (embossed pattern) 5 is formed in the foamed resin layer 2, the pattern printing layer 3, and the surface protective layer 4. FIG.
In such a configuration, since the surface protective layer 4 covers the pattern printing layer 3 and the foamed resin layer 2, the surface protective layer 4 is light in weight while having high surface strength and a necessary and sufficient thickness, and further darkened without causing whitening. A foam wallpaper having high suitability for printing and a method for producing the same can be provided.

(2) The manufacturing method of the foam wallpaper 10 which concerns on this embodiment contains the inorganic filler in the range of 50 to 150 mass parts on the paper base material 1 with respect to 100 mass parts of aqueous | water-based emulsion resin. The foaming agent-containing resin layer is formed by applying a paste containing the foaming agent in the range of 1 part by mass or more and 20 parts by mass or less so that the basis weight is in the range of 50 g / m ² or more and 150 g / m ² or less. A step of printing a pattern printing layer 3 having a pattern on the foaming agent-containing resin layer, a step of forming the surface protective layer 4 on the pattern printing layer 3, and a laminate including the above-described layers. In the step of heating the laminated body, the paper surface temperature of the laminated body at the exit of the embossed heater is in the range of 160 ° C to 200 ° C, and the temperature range Within the foaming agent-containing resin layer The foaming agent contained is heated and foamed to form the foamed resin layer 2, and immediately after passing through the embossing heater (that is, with the paper surface temperature of the laminate maintained within the range of 160 ° C to 200 ° C) The laminate is pressed within a range of 9800 N / m or more and 24500 N / m or less to give a concavo-convex shape (embossed pattern) 5 to the foamed resin layer 2, the pattern printing layer 3 and the surface protective layer 4.

  With such a configuration, the density of the surface protective layer 4 is increased by applying a certain temperature and pressure to the surface protective layer 4 during embossing, and the pattern printing layer 3 and the foamed resin layer under the surface protective layer 4 2 is densely covered with the surface protective layer 4. Thereby, the surface strength of the foam wallpaper 10 is improved by increasing the density of the surface protective layer 4, and at the same time, the foamed resin layer 2 is highly foamed by the coating with the surface protective layer 4. Therefore, the resin layer of the foamed resin layer 2 can be reduced. Moreover, the whitening by the crack of the pattern printing layer 3 can be prevented.

(3) In this embodiment, the aqueous emulsion resin may be an ethylene-vinyl acetate copolymer resin.
If it is such a structure, it will become easy to extrude and form the foamed resin layer 2 (foaming agent containing resin layer).
(4) Further, in the present embodiment, the basis weight of the surface protective layer 4 may be in the range of 10 g / ^{m 2} or more 40 g / ^{m 2} or less.
With such a configuration, the surface has sufficient surface strength, and the uneven shape of the surface by embossing can be reproduced sharply.

(5) In the present embodiment, the basis weight of the paper substrate 1 is in the range of 50 g / m ^{2 to} 100 g / m ² , the thickness of the paper substrate 1 is in the range of 80 μm to 150 μm, and foaming is performed. The basis weight of the resin layer 2 may be in the range of 50 g / m ² or more and 150 g / m ² or less, and the foaming ratio of the foamed resin layer 2 may be 4 times or more.
With such a configuration, the rigidity required for the wall covering material is secured. In addition, it has a sufficient volume for obtaining non-land concealment and has an excellent surface strength, and the surface irregularities due to embossing can be reproduced sharply.

<Example>
Examples of the present embodiment and comparative examples are shown below. In addition, this embodiment is not limited to the following Example.
[Example 1 to Example 9]
A plain paper (Nippon Paper Industries Co., Ltd .: “WK665IHT”) having a basis weight of 65 g / m ^{2 and a} thickness of 110 μm was used as the wallpaper backing paper (paper substrate 1). Next, a paste obtained by adding 80 parts of filler (inorganic filler) and 12 parts of capsule foaming agent to EVA resin (manufactured by Sumika Chemtex: “S-7400 (HQ)”) so as to have a basis weight of 100 g / m ^2. A foaming agent-containing resin layer was formed by coating on a backing paper for wallpaper by a coating method. Then, after carrying out pattern printing by gravure printing using the water-based ink on the foaming agent containing resin layer, the surface protective layer was formed so that it might become a basic weight of 20 g / m < ² > by the lip coater method. Thus, a laminate according to this example was produced. Thereafter, the foaming agent contained in the laminate was heated and foamed, and at the same time, an embossing roll imparted an uneven shape to the foamed wallpaper at an immediately preceding surface temperature of 160 ° C. and an embossing pressure of 9800 N / m. Finally, the embossed foamed wallpaper was cooled and dried to obtain the wall covering material of this example. Examples 2 to 9 were performed under the conditions shown in Table 1.

[Comparative Example 1]
A plain paper (Nippon Paper Industries Co., Ltd .: “WK665IHT”) having a basis weight of 65 g / m ^{2 and a} thickness of 130 μm was used as the wallpaper backing paper (paper substrate 1). Also, a paste in which 80 parts of filler (inorganic filler) and 12 parts of capsule foaming agent are added to EVA resin (manufactured by Sumika Chemtex: “S-7400 (HQ)”) is coated to a basis weight of 100 g / m ^2. The foaming agent-containing resin layer was formed by coating on the backing paper for wallpaper by the method. Then, pattern printing was performed on the foaming agent-containing resin layer by gravure printing using water-based ink. Thus, a laminate according to this comparative example was created. Thereafter, the foaming agent contained in the laminate was heated and foamed, and at the same time, an embossing roll imparted an uneven shape to the foamed wallpaper at an immediately preceding surface temperature of 150 ° C. and an embossing pressure of 9800 N / m. Finally, the embossed foamed wallpaper was cooled and dried to obtain the wall covering material of this comparative example.

[Comparative Example 2]
A plain paper (Nippon Paper Industries Co., Ltd .: “WK685AP”) having a basis weight of 85 g / m ^{2 and a} thickness of 130 μm was used as the wallpaper backing paper (paper substrate 1). Also, a paste in which 80 parts of filler (inorganic filler) and 12 parts of capsule foaming agent are added to EVA resin (manufactured by Sumika Chemtex: “S-7400 (HQ)”) is coated to a basis weight of 100 g / m ^2. The foaming agent-containing resin layer was formed by coating on the backing paper for wallpaper by the method. Then, after carrying out pattern printing by gravure printing using the water-based ink on the foaming agent containing resin layer, the surface protective layer was formed so that it might become a basic weight of 20 g / m < ² > by the lip coater method. Thus, a laminate according to this comparative example was created. Thereafter, the foaming agent contained in the laminate was heated and foamed, and at the same time, an embossing roll imparted an uneven shape to the foamed wallpaper at an immediately preceding surface temperature of 150 ° C. and an embossing pressure of 9800 N / m. Finally, the embossed foamed wallpaper was cooled and dried to obtain the wall covering material of this comparative example.

[Comparative Example 3]
A plain paper (Nippon Paper Industries Co., Ltd .: “WK665IHT”) having a basis weight of 65 g / m ^{2 and a} thickness of 110 μm was used as the wallpaper backing paper (paper substrate 1). Also, a paste in which 80 parts of filler (inorganic filler) and 12 parts of capsule foaming agent are added to EVA resin (manufactured by Sumika Chemtex: “S-7400 (HQ)”) is coated to a basis weight of 160 g / m ^2. The foaming agent-containing resin layer was formed by coating on the backing paper for wallpaper by the method. Then, after carrying out pattern printing by gravure printing using the water-based ink on the foaming agent containing resin layer, the surface protective layer was formed so that it might become a basic weight of 20 g / m < ² > by the lip coater method. Thus, a laminate according to this comparative example was created. Thereafter, the foaming agent contained in the laminate was heated and foamed, and at the same time, an embossing roll imparted an uneven shape to the foamed wallpaper at an immediately preceding surface temperature of 150 ° C. and an embossing pressure of 9800 N / m. Finally, the embossed foamed wallpaper was cooled and dried to obtain the wall covering material of this comparative example.

[Comparative Example 4]
A foam wallpaper produced in the same manner as in Example 1 except that the basis weight of the surface protective layer was changed to 5 g was used as the wall covering material of this comparative example.
(Evaluation method)
The surface strength is evaluated by visually observing the damaged state of the surface when scratched by a test based on the “Surface Strengthened Wallpaper Performance Rules” established by the Wallpaper Industry Association, and evaluating whether or not the base paper layer (paper substrate) is exposed. did. The case where the base paper layer was not exposed was indicated by “◯”, and the case where the base paper layer was exposed was indicated by “X”.
The surface condition was visually checked to determine whether the surface of the pre-foamed product was cracked or roughened due to insufficient drying, and whether there was whitening due to cracks in the pattern print layer. The case where no whitening or the like occurred was indicated by “白”, the case where whitening or the like hardly occurred was indicated by “◯”, and the case where whitening or the like occurred was indicated by “X”.
For the product thickness, the thickness of the wall covering after embossing was measured using a dial gauge.
The evaluation results are shown in Table 1.

The foamed wallpaper of Examples 1 to 9 is a foamed wallpaper having high surface strength and high suitability for dark printing without causing whitening because both the surface strength and the surface state were “◯” or more. It could be confirmed. In addition, since the foamed wallpaper of Examples 1 to 9 had a product thickness of “600 μm”, it was confirmed that the foamed wallpaper was sufficient to obtain a non-land concealing property. Moreover, since the product weight of Examples 1-9 was "185 g / m < ² >", it has confirmed that it was a foam wallpaper which realized weight reduction.
On the other hand, the foamed wallpaper of Comparative Example 1 had a surface strength of “x”. This is considered because the surface protective layer is not provided.
Further, the foamed wallpaper of Comparative Example 2 had a surface strength of “x”. This is presumably because the paper surface temperature in the vicinity of the exit of the embossed heater did not reach an appropriate temperature.

The foamed wallpaper of Comparative Example 3 had a surface strength and a surface state of “◯”, but the product weight was “265 g / m ² ”. This is probably because the basis weight of the paste applied in Comparative Example 3 was not an appropriate amount.
Further, the foamed wallpaper of Comparative Example 4 was “x” in both surface strength and surface condition. This is probably because the basis weight of the surface protective layer applied in Comparative Example 4 was not an appropriate amount.
From the above results, it is possible to prevent the whitening of the foamed wallpaper by forming the foamed resin layer, the pattern printing layer, and the surface protective layer in the configuration as in the present embodiment while arranging elements such as strength, thickness, and weight reduction. It was found effective in terms of

The foam wallpaper according to the present embodiment can be used for wall decorations of buildings such as detached houses, apartment houses, stores, office buildings and the like.
While the present invention has been described with reference to specific embodiments, it is not intended that the invention be limited by these descriptions. From the description of the invention, other embodiments of the invention will be apparent to persons skilled in the art, along with various variations of the disclosed embodiments. Therefore, it is to be understood that the claims encompass these modifications and embodiments that fall within the scope and spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Paper base material 2 ... Foamed resin layer 3 ... Pattern printing layer 4 ... Surface protective layer 5 ... Embossed pattern 10 ... Foam wallpaper

Claims (10)

A paper substrate;
A foamed resin layer formed of a resin composition containing an aqueous emulsion resin, a foaming agent, and an inorganic filler;
A pattern printing layer having a pattern by printing;
A surface protective layer containing a resin and a filler is laminated in this order,
The same embossed pattern is formed on the foamed resin layer, the pattern printing layer, and the surface protective layer,
The resin composition contains an inorganic filler in a range of 50 to 150 parts by mass and a foaming agent in a range of 1 to 20 parts by mass with respect to 100 parts by mass of the aqueous emulsion resin. ,
The basis weight of the resin composition is in the range of 50 g / m ² or more and 150 g / m ² or less. ^2. The foamed wallpaper according to claim 1, wherein the surface protective layer has a basis weight in a range of 10 g / m ² or more and 40 g / m ² or less. The paper substrate has a basis weight in the range of 50 g / m ^{2 to} 100 g / m ² and a thickness in the range of 80 μm to 150 μm,
The foamed resin layer is in the range basis weight of 50 g / m ² or more 150 g / m ² or less, and the foam of claim 1 or claim 2, characterized in that it is more than four times expansion ratio wallpaper. The foamed wallpaper according to any one of claims 1 to 3, wherein a total basis weight of the foamed wallpaper is 200 g / m ² or less.   The foamed wallpaper according to any one of claims 1 to 4, wherein the aqueous emulsion resin is an ethylene-vinyl acetate copolymer resin. On the paper substrate, the inorganic filler is contained in the range of 50 to 150 parts by mass with respect to 100 parts by mass of the aqueous emulsion resin, and the foaming agent is contained in the range of 1 to 20 parts by mass. Applying a paste to be formed so that the basis weight is in a range of 50 g / m ² or more and 150 g / m ² or less to form a foaming agent-containing resin layer;
Printing a pattern printing layer having a pattern on the foaming agent-containing resin layer;
Forming a surface protective layer on the pattern printing layer;
And a step of heating the laminated body provided with each layer through an embossed heater,
In the step of heating the laminated body, the paper surface temperature of the laminated body at the outlet of the emboss heater is in a range of 160 ° C. or higher and 200 ° C. or lower, and the foaming agent contained in the foaming agent-containing resin layer within the temperature range. The foamed resin layer is formed by heating and foaming the agent,
Immediately after passing through the embossing heater, the laminate is pressurized with an embossing roll within a range of 9800 N / m to 24500 N / m, and an embossed pattern is formed on the foamed resin layer, the pattern printing layer, and the surface protective layer. A method for producing foamed wallpaper, characterized by comprising:   After passing through the embossing heater, the laminate is added within the range of 9800 N / m to 24500 N / m with an embossing roll while maintaining the paper surface temperature of the laminate within a range of 160 ° C. to 200 ° C. The method for producing foam wallpaper according to claim 6, wherein an embossed pattern is simultaneously applied to the foamed resin layer, the pattern printing layer, and the surface protective layer.   The method for producing a foam wallpaper according to claim 6 or 7, wherein the aqueous emulsion resin is an ethylene-vinyl acetate copolymer resin. The method for producing a foam wallpaper according to any one of claims 6 to 8, wherein the surface protective layer has a basis weight in a range of 10 g / m ² or more and 40 g / m ² or less. The paper substrate has a basis weight in the range of 50 g / m ^{2 to} 100 g / m ² and a thickness in the range of 80 μm to 150 μm,
The foamed resin layer has a basis weight in the range of 50 g / m ² or more and 150 g / m ² or less, and has an expansion ratio of 4 times or more. The manufacturing method of the foam wallpaper as described in a term.

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