JP2012076344A - Functional wallpaper having decomposing performance of volatile organic compound and antibacterial performance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide functional wallpaper which is excellent in antibacterial (sterilization) performance in addition to the decomposing action of a volatile organic compound such as an aldehyde, and particularly can exert antibacterial (sterilizing) action even during the non-irradiation of light such as a nighttime.SOLUTION: The functional wallpaper includes an intermediate layer provided on a wallpaper base material including a foam resin layer; and a visible light type photocatalyst layer containing a visible light type photocatalyst compound and an inorganic antibacterial agent layer containing an inorganic antibacterial agent which are provided on the intermediate layer.

Description

  The present invention relates to wallpaper. More specifically, the present invention relates to a functional wallpaper having the ability to decompose volatile organic compounds such as aldehydes in the atmosphere and antibacterial performance.

As countermeasures against the problem of sick house caused by volatile organic compounds such as aldehydes, various interior materials for buildings having the ability to decompose volatile organic compounds (particularly wallpaper having the largest area as interior materials) have been studied. Patent Documents 1 and 2 propose an interior material provided with a coating layer containing a material (photocatalyst such as titanium oxide) that decomposes a volatile organic compound by light irradiation.
Bacteria are found in many places in daily life and grow exponentially if the growth conditions are in place, leading to problems such as bad odor, slime, food poisoning, illness, etc. However, it can be said that the photocatalyst is a promising material in that it also has antibacterial (sterilizing) performance for suppressing and killing bacterial growth.
However, since the photocatalyst exhibits its performance by light irradiation, there is a problem that bacteria increase when light is not irradiated at night and the like, and it cannot be said that its antibacterial performance is sufficient.

JP 2000-225669 A JP 2002-155498 A

  The present invention has been made in view of the above-mentioned problems of the prior art, and in addition to the action of decomposing volatile organic compounds such as aldehydes, functional wallpaper excellent in antibacterial (bactericidal) performance, particularly at night. The present invention provides a functional wallpaper that exhibits an antibacterial (bactericidal) action even when no light is irradiated.

The present invention
(1) Having an intermediate layer on a wallpaper substrate including a foamed resin layer, and having a visible light photocatalyst layer containing a visible light photocatalyst compound and an inorganic antibacterial agent layer containing an inorganic antibacterial agent on the intermediate layer Functional wallpaper,
(2) The functional wallpaper according to (1), wherein the inorganic antibacterial agent is a silver-based antibacterial agent containing silver,
(3) The functional wallpaper according to (1) or (2), wherein the visible light type photocatalyst layer is disposed on the inorganic antibacterial agent layer,
(4) The functional wallpaper according to (3), wherein the inorganic antibacterial agent layer has a pattern shape,
(5) The functional wallpaper according to (4), wherein a coverage of the visible light photocatalyst layer with the inorganic antibacterial agent layer is 50% or less,
(6) The functional wallpaper according to any one of (1) to (5), wherein the inorganic antibacterial agent layer further contains a visible light type photocatalytic compound,
(7) The functional wallpaper according to any one of (1) to (6), wherein the intermediate layer contains an inorganic adsorbent,
(8) The functional wallpaper according to (1) to (7), wherein the visible light photocatalyst layer further contains an inorganic adsorbent,
(9) The functionality according to (1) to (8), further including a second intermediate layer containing an inorganic adsorbent and a visible light type photocatalytic compound between the intermediate layer and the visible light type photocatalyst layer. wallpaper,
(10) The functional wallpaper according to any one of (1) to (9), wherein the wallpaper base material further includes a first non-foamed resin layer on an upper surface of the foamed resin layer, and (11) The functional wallpaper according to any one of (1) to (10), wherein the wallpaper base material further includes a second non-foamed resin layer on the lower surface of the foamed resin layer,
Is to provide.

  The functional wallpaper of the present invention adds antibacterial performance due to inorganic antibacterial agents that develop not only during light irradiation but also during non-light irradiation to the volatile organic compound decomposition performance and antibacterial performance due to the photocatalyst that appears during light irradiation. It can exhibit excellent volatile organic compound decomposition performance and antibacterial performance.

FIG. 1 is a schematic diagram showing the wallpaper produced in Example 1. FIG. FIG. 2 is a schematic diagram showing the wallpaper produced in Example 2. FIG. FIG. 3 is a schematic diagram showing the wallpaper produced in Example 3. FIG. 4 is a schematic diagram showing a comparative wallpaper produced in Comparative Example 1.

Hereinafter, the functional wallpaper of the present invention (hereinafter simply referred to as “wallpaper”) will be described.
The wallpaper of the present invention has an intermediate layer on a wallpaper substrate including a foamed resin layer, a visible light type photocatalyst layer containing a visible light type photocatalytic compound on the intermediate layer, and an inorganic antibacterial agent containing an inorganic antibacterial agent Has a layer.
The inorganic antibacterial agent layer is located on the intermediate layer together with the visible light type photocatalyst layer, but the positional relationship between the inorganic antibacterial agent layer and the visible light type photocatalyst layer is arbitrary. That is, the positional relationship of wallpaper substrate / intermediate layer / visible light type photocatalyst layer / inorganic antibacterial agent layer from the lower side (wallpaper substrate side) or wallpaper substrate / intermediate layer / inorganic antibacterial agent layer / visible light The positional relationship of the type photocatalyst layer may be used. It is preferable to provide an inorganic antibacterial agent layer on the visible light type photocatalyst layer in that the antibacterial action of the inorganic antibacterial agent is more effectively exhibited.

(1) Wallpaper base material The wallpaper of this invention has a wallpaper base material. The wallpaper base material includes at least a foamed resin layer, and may further include a first non-foamed resin layer, a backing sheet layer, and / or a second non-foamed resin layer as necessary.

(1-1) Foamed resin layer The wallpaper base material of this invention contains a foamed resin layer. The foamed resin layer is a layer formed by foaming a layer containing a foaming agent and a resin (hereinafter referred to as “unfoamed resin layer”).
The resin contained in the unfoamed resin layer is not particularly limited as long as it is foamed by the action of a foaming agent (for example, foamed when heated), but is preferably an olefin resin, An ethylene resin is more preferable.
Examples of ethylene resins include ethylene homopolymer resin (PE), ethylene-vinyl acetate copolymer resin (EVA), ethylene-methyl acrylate copolymer resin (EMA), and ethylene-ethyl acrylate copolymer resin (EEA). ), An ethylene-based copolymer resin such as an ethylene-alkyl acrylate copolymer resin having 3 to 5 carbon atoms, an ethylene-methyl methacrylate copolymer resin (EMMA), an ethylene-methacrylic acid copolymer resin (EMAA), Examples thereof include a mixture of these resins. These resins can be easily crosslinked by irradiating ionizing radiation described later. Among these resins, EVA resin and EMAA resin are preferable.
Examples of olefin resins other than ethylene resins include polypropylene resins, polybutene resins, and polymethylpentene resins.

When an EVA resin is used as the resin component, the vinyl acetate unit (copolymerization ratio) in the EVA resin is not particularly limited, but is preferably about 5 to 30% by weight, and about 10 to 20% by weight. More preferred. 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 40 to 70 g / 10 minutes. In the present specification, MFR is a value measured by a test method described in JIS K 7210 (Method for testing the flow 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 the foamed cell, the foamed cell density, etc.) is not particularly limited, and can be appropriately designed within a range not impairing the scope of the present invention.
Moreover, when using EMAA resin as a resin component, it is preferable that the methacrylic acid unit (copolymerization ratio) in EMAA resin is about 4 to 20 weight%. The melt flow rate value (JIS K 7210, 190 ° C., 2.16 kg) of the resin component depends on the type of polymer to be used, but is usually preferably 60 to 200 g / 10 minutes. In particular, it is advantageous in that a good foamed state can be maintained even in a high range of 100 to 200 g / 10 minutes.

The foaming agent used in the present invention may be a chemical foaming agent or a physical foaming agent, but a chemical foaming agent is preferred, and among the chemical foaming agents, a pyrolytic foaming agent is preferred.
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 blending amount of the pyrolytic foaming agent can be appropriately set according to the type of foaming agent, the expansion ratio, and the like. Since the expansion ratio is 1.5 times or more, preferably about 3 to 7 times, the blending amount of the pyrolytic foaming agent should be about 1 to 20 parts by mass with respect to 100 parts by mass of the resin component. Is preferred.
Examples of the physical foaming agent include thermal expansion type microcapsules. For example, a volatile liquid expansion agent such as propane, butane, isobutane, pentane, hexane or the like is used as a vinylidene chloride-acrylonitrile-divinylbenzene copolymer, methacrylate-acrylonitrile- A microcapsule encapsulated in a thermoplastic polymer polymer shell such as divinylbenzene copolymer having an average diameter in the range of 1 to 100 μm can be used.

The unfoamed resin layer may contain additives such as a cell regulator, an inorganic filler, and a pigment in addition to the foaming agent and the resin.
As the cell adjusting agent, for example, a metal soap such as zinc stearate can be used. The blending amount of the cell regulator is preferably about 0.3 to 10 parts by mass, and more preferably about 1 to 5 parts by mass with respect to 100 parts by mass 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 the inorganic filler, an effect of suppressing see-through, an effect of improving surface characteristics, and the like are obtained. About 0-100 mass parts is preferable with respect to 100 mass parts of resin components, and, as for the compounding quantity of this inorganic filler, about 20-70 mass parts 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. About 10-50 mass parts is preferable with respect to 100 mass parts of resin components, and, as for content of this pigment, about 15-30 mass parts is more preferable.
In addition, stabilizers, lubricants, and the like can be used as additives.
Although the thickness of a foamed resin layer is not specifically limited, About 20-200 micrometers is preferable and about 50-120 micrometers is more preferable.

(1-2) First Non-foamed Resin Layer The wallpaper base material of the present invention has a non-foamed resin layer (hereinafter referred to as “first non-foamed resin layer” to be distinguished from a second non-foamed resin layer described later) on the top surface of the foamed resin layer. A resin layer ”). The first non-foamed resin layer mainly protects the foamed resin layer and lowers the visible light photocatalytic function due to a volatile component such as a foamed gas in the foaming process when the foamed resin layer is formed (specifically, titanium oxide) And the like to prevent adverse effects on particles of visible light type photocatalyst compounds such as.
As the resin for forming the first non-foamed resin layer, the same olefin resin as that used for the foamed resin layer can be used. The resin used for the first non-foamed resin layer may be the same as or different from the resin type used for the foamed resin layer, but improves the adhesion between the first non-foamed resin layer and the foamed resin layer. Therefore, it is preferable to use the same type of resin or resin composition.

  As the resin component, for example, a copolymer obtained by a combination of at least one monomer of acrylic acid and methacrylic acid and ethylene can be suitably used as the resin component. More specifically, it is desirable to use at least one of an ethylene-methacrylic acid copolymer, an ethylene-acrylic acid copolymer, and an ionomer resin. As the ionomer resin, a resin having a structure in which the molecules of ethylene-methacrylic acid copolymer and / or ethylene-acrylic acid copolymer are intermolecularly bonded with metal ions such as sodium and zinc can be used. When such a resin component is used, it is possible to form a strong layer particularly due to hydrogen bonds in the resin, so that excellent scratch resistance, 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. Although the thickness of a non-foaming resin layer is not specifically limited, About 10-50 micrometers is preferable and especially about 10-20 micrometers is more preferable. Moreover, although content of the said resin component in a resin composition is not limited, Usually, it is preferable to set suitably in the range of 70 to 100 weight%.
Although the melt flow rate value (MFR) of the resin component depends on the type of the resin component to be used, etc., it is generally set as appropriate within a range of 10 g / 10 minutes or more. Usually, it is preferably 10 to 100 g / 10 minutes, particularly preferably 10 to 95 g / 10 minutes, and more preferably 20 to 80 g / 10 minutes. By using a material having such a numerical range, more excellent scratch resistance, wear resistance and the like can be obtained. The measurement conditions for the melt flow rate value (MFR) are the same as those described in the section of the foamed resin layer.

  Preferred combinations as the foamed resin layer / first non-foamed resin layer include EVA resin / EVA resin, EMAA resin / EVA resin, EVA resin / EMAA resin, EMAA resin / EMAA resin, and PE resin / PE resin. EVA resin / EMAA resin is preferred.

(1-3) Backing Sheet Layer The wallpaper base material of the present invention may include a backing sheet layer. The backing sheet layer is provided on the lower surface of the foamed resin layer or on the lower surface of the second non-foamed resin layer described later. The backing sheet layer is not particularly limited. For example, a resin sheet, a fiber sheet such as paper can be generally used, but a fiber sheet such as paper is preferable. Specifically, flame retardant paper (pulp-based sheet is used). Treated with a flame retardant such as guanidine sulfamate, guanidine phosphate, and the like); inorganic paper containing inorganic additives such as aluminum hydroxide and magnesium hydroxide; fine paper; thin paper.
The basis weight of the backing sheet layer is not particularly limited, preferably about 50 to 300 g / m ^2, about 50 to 80 g / m ² is more preferable.

(1-4) Second Non-foamed Resin Layer The wallpaper base material of the present invention has a non-foamed resin layer (hereinafter referred to as “second non-foamed resin layer” in order to distinguish it from the above-mentioned first non-foamed resin layer). A resin layer ”). When the wallpaper substrate includes a backing sheet layer, a second non-foamed resin layer may be included between the foamed resin layer and the backing sheet layer, and the second non-foamed resin layer functions as an adhesive layer. Excellent adhesion can be obtained.
As the second non-foamed resin layer, the same olefin resin as that used for the foamed resin layer can be used, but an ethylene-vinyl acetate copolymer is preferably used from the viewpoint of improving adhesion. it can. Although a 2nd non-foaming resin layer may contain a well-known additive other than a resin component, it is preferable to mix | blend so that content of a resin component may be 70 to 100 weight%.

[Method for forming wallpaper substrate]
The wallpaper base material of the present invention includes (a) a step of forming a pre-foaming wallpaper base material including an unfoamed resin layer, and (a) a step of foaming the unfoamed resin layer to form a foamed resin layer. It is formed.
Since the unfoamed resin layer is foamed in the step (a) to form the foamed resin layer, the pre-foaming wallpaper substrate including the unfoamed resin layer is changed to the wallpaper substrate including the foamed resin layer in the step (a). And change. That is, the “pre-foaming wallpaper base material” and the “wallpaper base material” are obtained by distinguishing the name before foaming and the name after foaming for convenience.

(A) The process of forming the wallpaper base material before foaming including an unfoamed resin layer Although the formation method of the wallpaper base material before foaming is not specifically limited, For example, it can form with a T-die extruder.
When forming a pre-foaming wallpaper substrate including not only an unfoamed resin layer but also a first non-foamed resin layer, two layers can be simultaneously formed by simultaneously extruding molten resin corresponding to the two layers. A multi-manifold type T-die can be used. In this case, the resin composition for forming the unfoamed resin layer and the resin composition for forming the first non-foamed resin layer are placed in separate cylinders, and two types and two layers are simultaneously extruded to form and laminate do it.
Similarly, when forming a pre-foaming wallpaper substrate including an unfoamed resin layer, a first non-foamed resin layer, and a second non-foamed resin layer, a resin composition for forming an unfoamed resin layer, the first If the resin composition for forming the non-foamed resin layer and the resin composition for forming the second non-foamed resin layer are put in separate cylinders, three types and three layers are extruded simultaneously to form a film and laminate Good.

  In order to form a pre-foaming wallpaper substrate including a backing sheet layer, the laminate coextruded by the above method may be simultaneously laminated (film formation) on the backing sheet layer. The resin layer laminated simultaneously with extrusion on the backing sheet layer is bonded to the backing sheet layer because it has adhesiveness by heat melting. Alternatively, a laminate in which films are simultaneously formed in advance may be prepared, placed on the backing sheet layer, and bonded by thermal lamination.

  When the resin composition forming the unfoamed resin layer contains an inorganic filler, when the unfoamed resin layer is formed by extrusion molding, the residue of the inorganic filler at the extrusion port (so-called die) of the extrusion molding machine (So-called eyes) are likely to occur, and this tends to be a foreign matter on the sheet surface. Therefore, when the non-foamed resin layer contains an inorganic filler, the resin composition for forming the first non-foamed resin layer and the second non-foamed resin layer is replaced with the resin composition for forming the non-foamed resin layer. At the same time, it is preferable to perform coextrusion molding. The coextrusion molding can be performed, for example, by using a multi-manifold type T die. In this way, the co-extrusion molding is performed in such a manner that the non-foamed resin layer is sandwiched between the two non-foamed resin layers (the first non-foamed resin layer and the second non-foamed resin layer), thereby suppressing the occurrence of the above-mentioned eye spots. it can.

The pre-foaming wallpaper substrate may be irradiated with an electron beam. Thereby, since a resin component can be bridge | crosslinked, the surface strength of a wallpaper base material, a foaming degree, 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. The crosslinking can also be performed using a chemical crosslinking agent (also referred to as a crosslinking agent or a crosslinking aid).
When performing electron beam irradiation, you may contain a crosslinking agent in a resin composition. 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 cross-linking agent is preferably about 0 to 10 parts by mass, more preferably 1 to 4 parts by mass with respect to 100 parts by mass of the resin component.

(A) Step of foaming the unfoamed resin layer to form a foamed resin layer The method of foaming the unfoamed resin layer is appropriately selected from known methods according to the type of foaming agent, and is particularly limited. Not.
When a pyrolytic foaming agent is used as the foaming agent, the heating conditions are not limited as long as the foamed resin layer is formed by the decomposition of the pyrolytic foaming agent, but the heating temperature is preferably about 210 to 240 ° C. The time is preferably about 20 to 80 seconds.
In addition, it is preferable to perform a process (I) after apply | coating the coating liquid for outermost surface layer formation (the coating liquid for visible light type photocatalyst layer formation, and the coating liquid for inorganic antibacterial agent layer formation). By simultaneously drying the coating liquid to form the outermost surface layer and foaming the non-foamed resin layer, the number of manufacturing steps can be reduced and the cost can be reduced. In addition, when the pattern layer, the intermediate layer, the visible light type photocatalyst layer, and the inorganic antibacterial agent layer were formed after foaming, it was difficult to apply the layer neatly due to the unevenness of the foamed resin layer, By forming the layer before foaming, it can be applied neatly.

(2) Intermediate layer The wallpaper of the present invention has an intermediate layer. When the visible light type photocatalyst layer is provided directly on the wallpaper base material or the pattern layer, the photocatalyst function is consumed for decomposing organic substances such as resins existing in these layers, and the photocatalyst function may be lowered. Moreover, there exists a possibility that a wallpaper base material and a pattern layer may deteriorate by the said decomposition | disassembly, or adhesiveness may fall. In particular, when embossing is applied to improve design and adhesion, the visible light photocatalyst compound is easily embedded in the pattern layer or wallpaper substrate located under the visible light photocatalyst layer. The problem is likely to occur. In the present invention, by providing an intermediate layer between the visible light type photocatalyst layer and the wallpaper substrate or the pattern layer, these problems can be suppressed.

The intermediate layer is formed of an inorganic material or an organic / inorganic hybrid material, and it is preferable to use an inorganic material from the viewpoint of sustaining the photocatalytic function.
Examples of inorganic materials include alkoxysilanes condensates, organopolysiloxanes, polycondensates of organic polysiloxane compounds, hydrolysates, silica compounds such as silicon varnish; zinc phosphate, polyphosphate, phosphoric acid Examples thereof include phosphates such as aluminum; inorganic binders such as silica, colloidal silica, water glass, cement, lime, gypsum, frit for enamel, glaze for glass lining, and plaster.
As the organic / inorganic hybrid material, known and commercially available materials can be used. For example, an undercoat agent “STK-102” manufactured by Ishihara Sangyo Co., Ltd. can be used. When organic / inorganic hybrid materials are used, the inorganic components are unevenly distributed to the visible light photocatalyst layer and the organic components are unevenly distributed to the wallpaper base material due to the compatibility of the materials. Can be suppressed.

The intermediate layer of the present invention may contain an inorganic adsorbent. The inorganic adsorbent can positively adsorb organic matter, nitrogen oxides, etc. in the atmosphere when no light is irradiated such as at night. Moreover, the inorganic adsorbent of the intermediate layer can prevent a decrease in the photocatalytic function due to the volatile component by adsorbing a volatile component such as a foaming gas generated in the foaming step when forming the foamed resin layer.
The content of the inorganic adsorbent in the intermediate layer of the present invention is preferably 5 to 95% by mass, more preferably 30 to 70% by mass.

Examples of the inorganic adsorbent include, but are not limited to, zeolite, hydroxyapatite, inorganic salt carrying an amine compound, and the like. From the viewpoint of adsorption performance, mordenite type, Y type, and ZSM-5 type zeolite are preferable, and ZSM-5 type zeolite subjected to hydrogen ion exchange (for example, HSZ-800 manufactured by Tosoh Corporation) is more preferable.
Although it does not specifically limit as a coating amount of an intermediate | middle layer, 0.2-5 g / m < ² > is preferable. In the present specification, the “coating amount” refers to the weight after drying unless otherwise specified.

[Method for forming intermediate layer]
The intermediate layer of the present invention can be formed by applying an intermediate layer coating solution on a pre-foaming wallpaper substrate and then drying it. An intermediate layer coating solution may be applied on the wallpaper substrate (that is, an intermediate layer coating solution is applied after foaming), but it becomes difficult to apply the intermediate layer cleanly due to the unevenness of the foamed resin layer. It is preferable to apply the intermediate layer coating liquid on the pre-foaming wallpaper substrate (that is, apply the intermediate layer coating liquid before foaming).
The intermediate layer coating liquid contains the above-described inorganic material or organic / inorganic hybrid material (and inorganic adsorbent if necessary) and a solvent. The solvent is not particularly limited, and examples thereof include water; an aqueous medium such as a mixed solvent of alcohols such as ethanol, methanol, 2-propanol, and butanol and water; Among these, water is particularly preferable.
In forming the intermediate layer using the intermediate layer coating liquid of the present invention, for example, the intermediate layer coating liquid is applied by a conventionally known method such as spin coating, dip coating, doctor blade, spraying or brushing, and then the intermediate layer coating liquid is applied. What is necessary is just to heat at the temperature which can remove the solvent in a layer coating liquid.

(3) Visible Light Type Photocatalyst Layer The wallpaper of the present invention has a visible light type photocatalyst layer containing a visible light type photocatalytic compound (hereinafter, sometimes simply referred to as “photocatalytic compound”).
The photocatalytic compound is not particularly limited as long as it is a compound that exhibits a photocatalytic action with visible light, but is preferably a compound that exhibits photocatalytic activity against light irradiation by a fluorescent lamp. Specifically, a compound exhibiting photocatalytic activity for light irradiation with a wavelength of about 430 nm to about 830 nm is preferable.
Specific examples of the photocatalytic compound include Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc, Re, Fe, Co, as disclosed in JP-A-2007-268523. , Ni, Ru, Rh, Pd, Os, Ir, Pt, Cu, Ag, Au, Zn, Cd, Ga, In, Tl, Ge, Sn, Pb, Bi, La, Ce Alternatively, two or more kinds of oxides, nitrides, sulfides, oxynitrides, oxysulfides, nitrofluorides, oxyfluorides, oxynitrofluorides, and the like can be given. Among these, anatase-type or rutile-type titanium oxide is preferable, and anatase-type titanium oxide is preferable as a catalyst that shows catalytic activity when irradiated with visible light or fluorescent light.
As a method for producing titanium oxide particles having visible light responsiveness, the production methods disclosed in JP-A Nos. 2001-278625, 2001-302241, 2003-275600 and the like are used. Can do.
The content of the photocatalytic compound in the visible light type photocatalyst layer of the present invention is preferably 5 to 95% by mass, and more preferably 10 to 60% by mass.

The visible light type photocatalyst layer of the present invention is obtained by adding a photocatalyst compound to a binder. When a resin composition (organic binder) is used as a binder for the visible light photocatalyst layer, the visible light photocatalyst compound is dispersed in the resin composition or exists in a state coated with a resin. Is not sufficiently exposed, and the visible light photocatalytic function may not be sufficiently developed. Therefore, in the present invention, an inorganic binder is used rather than an organic binder as a binder for the visible light photocatalyst layer, and the photocatalyst compound is exposed on the surface of the visible light photocatalyst layer as a porous layer. desirable.
Specific examples of inorganic binders include condensates of alkoxysilanes, organopolysiloxanes, polycondensates of organic polysiloxane compounds, hydrolysates, silica compounds such as silicon varnish; zinc phosphate, polyphosphate, phosphoric acid Examples thereof include phosphates such as aluminum; inorganic binders such as silica, colloidal silica, water glass, cement, lime, gypsum, frit for enamel, glaze for glass lining, and plaster.
1-70 mass% is preferable and, as for content of the binder in the visible light type photocatalyst layer of this invention, 5-50 mass% is more preferable.

The visible light photocatalyst layer of the present invention may further contain an inorganic adsorbent. Specific examples of the inorganic adsorbent contained in the visible light type photocatalyst layer include those exemplified as the inorganic adsorbent that can be contained in the intermediate layer, and preferred specific examples are also the same.
When an inorganic adsorbent is also contained in the visible light type photocatalyst layer, there is an advantage that the adsorption performance of organic substances, nitrogen oxides, etc. in the atmosphere at the time of no light irradiation such as at night can be further improved. On the other hand, since the amount of the substance that can be held by the inorganic binder of the visible light type photocatalyst layer is not infinite, it may be necessary to reduce the amount of the visible light type photocatalytic compound corresponding to the added amount of the inorganic adsorbent. In such a case, there exists a fault that the decomposition | disassembly performance and antibacterial performance of a volatile organic compound at the time of light irradiation will fall. Therefore, the respective contents of the photocatalytic compound and the inorganic adsorbent in the visible light photocatalyst layer are appropriately determined according to the use environment of the wallpaper while taking the above advantages and disadvantages into consideration. Although not limited, the content of the inorganic adsorbent in the visible light photocatalyst layer is preferably 10 parts by mass to 60 parts by mass with respect to 100 parts by mass of the visible light photocatalyst compound.

The visible light type photocatalyst layer of the present invention may further contain a matting agent. By adding a matting agent to the visible light photocatalyst layer, the wallpaper can be given a matte feeling. The particle size of the matting agent is preferably 0.5 to 7 μm, more preferably 1 to 6.5 μm, and particularly preferably 2 to 5 μm. If it is smaller than 0.5 μm, the photocatalyst layer may have insufficient unevenness and the matting effect may not be sufficiently obtained. If the particle size is larger than 7 μm, the coating property may be lowered, the particle size may be excessive compared to the thickness of the visible light type photocatalyst layer film, and the matting agent may fall off. There is a possibility that the amount of the photocatalytic compound entering the side (the area where light is difficult to reach) increases and the photocatalytic function is deteriorated.
Examples of the matting agent material include particles mainly composed of an inorganic hollow body such as silica, mica, alumina, calcium carbonate, diatomaceous earth, silica sand, and shirasu balloon. Considering the oxidative decomposition performance of the photocatalytic compound, it is desirable that the material has as few organic components as possible, and silica having a high oil absorption is particularly preferable.
Although content of a matting agent is not specifically limited, 5-100 mass parts is preferable with respect to 100 mass parts of visible light type photocatalyst compounds.

Moreover, you may contain various additives as a dispersion in a visible light type photocatalyst layer as needed.
Examples of such additives include amorphous silica, silicon oxide such as silica sol, amorphous alumina, aluminum oxide and hydroxide such as alumina sol, aluminosilicate such as zeolite and kaolinite. Oxides and hydroxides of alkaline earth metals such as salts, magnesium oxide, calcium oxide, strontium oxide, barium oxide, magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, calcium phosphate, molecular sieve, activated carbon , And Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc, Re, Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, Pt, Cu, Ag, Au, Metal element hydroxides such as Zn, Cd, Ga, In, Tl, Ge, Sn, Pb, Bi, La, Ce Beauty and amorphous oxides of these metal elements and the like.
These additives may be only one type or two or more types.
Although it does not specifically limit as a coating amount of a visible light type photocatalyst layer, 0.2-5 g / m < ² > is preferable.

[Method for forming visible light photocatalyst layer]
The visible light photocatalyst layer of the present invention includes, for example, a dispersion in which a visible light photocatalyst compound and an inorganic binder are dispersed in a solvent (hereinafter also referred to as “visible light photocatalyst dispersion”), gravure coating, spray coating, Examples of the method include coating on the intermediate layer (or inorganic antibacterial agent layer) by a method such as dip coating or brush coating, and then heating at a temperature at which the solvent in the dispersion can be removed. It is not limited.
The visible light photocatalyst dispersion liquid may be directly applied on the intermediate layer (or inorganic antibacterial agent layer), but it is also possible to produce a photocatalyst layer transfer film and transfer it by a transfer method. As a means for applying, for example, various application methods such as gravure coating, spray coating, and dip coating as described above can be selected. The coating liquid may be applied not only once but a plurality of times.
Thereafter, the solvent is removed by heating at a temperature at which the solvent can be removed. After drying is completed, aging can be performed for a required time at a temperature of about 30 to 60 ° C. Thereby, the peeling strength of the coated visible light type photocatalyst layer can be improved.

The photocatalyst compound present in the visible light type photocatalyst dispersion of the present invention may be in the form of particles or fibers. In the case of particles, the average primary particle size is usually 500 nm or less, preferably 200 nm or less, more preferably 180 nm or less, and the average secondary particle size is preferably 15 μm or less.
The content of the photocatalyst compound in the visible light type photocatalyst dispersion of the present invention is not particularly limited as long as it is appropriately set depending on the application, but usually the lower limit is 0.1% by weight or more, preferably 1% by weight or more. The upper limit is set to be 30% by weight or less. In addition, as the content of the photocatalytic compound (that is, the amount of powder in the dispersion) increases, the later-described mixing (particularly initial mixing) can be performed more efficiently. Taking this into consideration, the content of the photocatalyst compound is set to be higher than the predetermined amount at the time of preparation, and a desired content is obtained by adding a solvent and diluting in a later step. You can also.

  The aqueous solvent in the present invention contains water as a main component, and examples thereof include water; an aqueous medium such as a mixed solvent of alcohols such as ethanol, methanol, 2-propanol, and butanol and water; Among these, water is particularly preferable.

When obtaining the visible light type photocatalyst dispersion of the present invention, the mixture obtained by the above mixing is further subjected to operations such as removal of coarse particles, adjustment of photocatalyst compound content (dilution, etc.), pH adjustment and the like. Can be applied. There is no restriction | limiting in particular as a specific method of these operation, What is necessary is just to employ | adopt a conventionally well-known method.
When storing the visible light type photocatalyst dispersion liquid of the present invention, it is preferable to store it under conditions where it is not exposed to light. For example, the visible light type photocatalyst dispersion liquid is stored in a dark room or has an ultraviolet and visible light transmittance of 10 each. It is preferable to store it in a light-shielding container of no more than%.

(4) Inorganic antibacterial agent layer The wallpaper of this invention has an inorganic antibacterial agent layer containing an inorganic antibacterial agent.
As an inorganic antibacterial agent, a metal antibacterial agent containing at least one of antibacterial metals such as silver, copper, zinc, tin, lead, mercury, and cobalt exhibits an antibacterial action even when no light is irradiated at night. ,preferable. Among these, silver-based antibacterial agents containing silver are particularly preferable because of their excellent antibacterial action.
1-90 mass% is preferable, and, as for content of the inorganic antimicrobial agent in the inorganic antimicrobial agent layer of this invention, 10-60 mass% is more preferable.

The inorganic antibacterial agent layer of the present invention is obtained by adding an inorganic antibacterial agent to a binder. An inorganic binder can be suitably used as the binder of the inorganic antibacterial agent layer, and specific examples thereof include the same inorganic binders as those of the visible light type photocatalyst layer.
The inorganic antibacterial agent layer is composed of some or all of the ion-exchangeable ions of inorganic compound carriers such as zeolite, apatite, glass, silica gel, phosphate, zirconium phosphate, silver, copper, zinc, tin, lead, mercury It is formed by applying a coating liquid in which an ion-substituted substance substituted with ions such as cobalt is dispersed in a medium such as water together with a binder by a method such as gravure coating, spray coating, dip coating, or brush coating, and then drying. Can do. Among the above ion-substituted products, an ion-substituted product obtained by substituting part of the ion-exchangeable ions of zeolite and zirconium phosphate with silver ions is desirable from the viewpoint of safety and actual product. The content of metal ions supported on zeolite and zirconium phosphate is preferably 0.1 to 15% by weight in the case of silver ions and 0.1 to 8% by weight in the case of copper or zinc ions.
Examples of the ion-substituted substance substituted with silver ions include AIS-NAZ320 (manufactured by JGC Catalysts) carrying silver on magnesium metasilicate aluminumate, silver / zinc two-type antibacterial agent Amteclean Z (Matsushita Amtec), Silver-based inorganic antibacterial agent NOVALON (manufactured by Toagosei Co., Ltd.) is commercially available.
In addition, as a method of forming an inorganic antibacterial agent layer containing a silver antibacterial agent as an inorganic antibacterial agent, a coating liquid in which the above-described ion-substituted substance substituted with silver ions is dispersed in a medium such as water together with a binder is applied and dried. In addition to this method, there is also a method of applying and drying a silver-based liquid inorganic antibacterial agent containing silver or a silver compound in a molten state in a water-soluble silicic acid solution as disclosed in JP-A-2009-221119. As the silver-based liquid inorganic antibacterial agent, for example, Lunar Silver (manufactured by Antibacterial Kaken Co., Ltd.) is commercially available.

Silver antibacterial agents have two performance mechanisms, one is called “silver ion elution type”, and H such as —SH, —NH ₂ , —COOH, etc. present in bacteria is replaced with silver ions. For example, the mechanism is -SAg. The other is a mechanism called “non-eluting type” that sterilizes by reactive oxygen species. In order to express the function by both mechanisms, the silver antibacterial agent is preferably on the outermost surface. Therefore, as described above, it is preferable to provide an inorganic antibacterial agent layer on the visible light type photocatalyst layer.

When the inorganic antibacterial agent layer is provided on the visible light type photocatalyst layer, the inorganic antibacterial agent layer preferably has a pattern shape. By adopting the pattern shape, it is possible to ensure light irradiation to the visible light type photocatalyst layer and not to disturb the photocatalytic function. The line width of the pattern is preferably 10 to 200 μm, and the line pitch is preferably 10 to 200 μm. The coverage of the visible light type photocatalyst layer by the inorganic antibacterial agent layer is preferably 50% or less.
Examples of the pattern shape of the pattern layer include a mesh shape and a stripe shape, but are not limited thereto. In the case of a mesh shape, the unit cell shape may be a triangle such as a regular triangle or an unequal side triangle, a square such as a square, rectangle, trapezoid or rhombus, a polygon such as a hexagon or octagon, a circle or an ellipse. Used. A random mesh pattern or a pseudo-random mesh pattern can also be used.

The inorganic antibacterial agent layer may further contain a visible light type photocatalytic compound. When the inorganic antibacterial agent layer also contains a visible light type photocatalytic compound, it is possible to enhance the decomposition performance and antibacterial / bactericidal performance of the volatile organic compound during light irradiation.
Examples of the visible light type photocatalyst contained in the antibacterial agent layer include specific examples exemplified as the visible light type photocatalytic compound contained in the visible light type photocatalyst layer, and preferred specific examples are also the same.
The content of the visible light type photocatalyst in the inorganic antibacterial agent layer is preferably 5 to 95 parts by mass, more preferably 30 to 70 parts by mass with respect to 100 parts by mass of the inorganic antibacterial agent.
Although it does not specifically limit as a coating amount of an inorganic antibacterial agent layer, 0.2-5 g / m < ² > is preferable.

(5) Second Intermediate Layer The wallpaper of the present invention may have a second intermediate layer containing an inorganic adsorbent and a visible light photocatalytic compound between the intermediate layer and the visible light photocatalyst layer. By providing the second intermediate layer, further adsorption performance and decomposition performance can be imparted to the wallpaper.
Examples of the inorganic adsorbent contained in the second intermediate layer include the specific examples exemplified as the inorganic adsorbent that can be contained in the intermediate layer, and the preferred specific examples are also the same.
Examples of the visible light type photocatalyst compound contained in the second intermediate layer include specific examples exemplified as the visible light type photocatalyst compound contained in the visible light type photocatalyst layer, and preferred specific examples are also the same.
Examples of the matrix material of the second intermediate layer include materials exemplified as the inorganic material or the organic / inorganic hybrid material forming the intermediate layer.
The content of the inorganic adsorbent in the second intermediate layer is preferably 5 to 95% by mass, and more preferably 30 to 70% by mass.
The content of the photocatalytic compound in the second intermediate layer is preferably 5 to 95% by mass, and more preferably 30 to 70% by mass.
Although it does not specifically limit as a coating amount of a 2nd intermediate | middle layer, 0.2-5 g / m < ² > is preferable.

(6) Pattern Pattern Layer The wallpaper of the present invention may further have a pattern pattern layer between the wallpaper base material and the intermediate layer. The design pattern layer can impart design properties to the wallpaper. Examples of the pattern pattern in the pattern layer 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 wallpaper of the present invention. The pattern pattern layer can be formed, for example, by printing a pattern pattern on the surface of the wallpaper substrate. 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 unfoamed 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, a petroleum resin, Examples include 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, acetic acid- Ester organic solvents such as 2-ethoxyethyl; alcohol organic solvents such as methyl alcohol, ethyl alcohol, normal propyl alcohol, isopropyl alcohol, isobutyl alcohol, ethylene glycol, propylene glycol; acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc. Ketone-based organic solvents; ether-based organic solvents such as diethyl ether, dioxane, and tetrahydrofuran; dichloromethane, carbon tetrachloride, trichloroethylene, tetrachloroethylene Chlorinated organic solvents emissions and the like; 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.

  Hereinafter, the present invention will be specifically described with reference to examples. The present invention is not limited to the method described below.

(1) Creation of wallpaper and comparative wallpaper
[Example 1]
Using a known T-die extruder, the first non-foamed resin layer / the unfoamed resin layer / the second non-foamed resin layer are formed in this order so that the thickness of each layer is 15 μm / 100 μm / 10 μm, and three layers A laminate A comprising:
The resin used for the first non-foamed resin layer and the second non-foamed resin layer and the resin composition used for the non-foamed resin layer are as follows.
(A) Resin used for the first non-foamed resin layer and the second non-foamed resin layer:
-Ethylene-vinyl acetate copolymer (manufactured by Sumitomo Chemical Co., Ltd., trade name: Evertate CV5053), 100 parts by mass (b) Resin composition used for unfoamed resin layer:
・ Ethylene-vinyl acetate copolymer (manufactured by Sumitomo Chemical Co., Ltd., trade name: Evaate CV5053), 100 parts by mass ・ Foaming agent (manufactured by Eiwa Kasei, trade name: ADCA # 3), 4 parts by mass ・ Calcium carbonate ( Shiroishi Kogyo Co., Ltd., trade name: Whiteon H), 30 parts by mass Titanium dioxide (pigment) (DuPont, trade name: Taipure R-108), 20 parts by mass Light stabilizer (made by ADEKA, trade name) : OF-101), 1 part by mass ・ Crosslinking agent (manufactured by JSR Corporation, trade name: Obstar JVA-702), 1 part by mass

Next, a backing sheet layer (rice weighed 60 g / m ² , WK-FKKD, manufactured by Kojin Co., Ltd.) is laminated on the second non-foamed layer resin layer of the laminate A to obtain a laminate B (wall paper before foaming). Material). Thereafter, for the purpose of improving the surface strength of the laminate A, the laminate B was irradiated with an electron beam at 200 kV and 5 Mrad.

Next, by gravure printing, a texture pattern (pattern pattern layer) is printed on the first non-foamed resin layer surface of the laminate B using water-based ink (manufactured by Dainichi Seika Kogyo Co., Ltd., trade name: Hydrick), An intermediate layer coating solution (manufactured by Colcoat Co., Ltd., ethyl silicate 40 (hydrolyzed solution)) was applied thereon so that the weight after drying was 1 g / m ² to obtain a laminate C. A visible light photocatalyst coating liquid was applied onto the intermediate layer of the laminate C so that the weight after drying was 1 g / m ² to obtain a laminate D. Further, the inorganic antibacterial agent coating liquid is sprayed on the mesh-shaped pattern so as to cover about 50% of the outermost surface on the visible light photocatalyst layer side of the laminate D so that the weight after drying becomes 1 g / m ^2. A laminate E was obtained.
The composition of the visible light type photocatalyst coating liquid is as follows.
-Titanium oxide photocatalyst coating agent (manufactured by Sumitomo Chemical Co., Ltd., trade name: TC-S4115 (with inorganic binder) NV 5 wt%, titanium oxide particle size 100 nm), 100 parts by mass-Matting agent (melamine and silica Particles made of, manufactured by Nissan Chemical Industries, Ltd., trade name: Opt beads 3500M, particle size 3.5 μm), 3.5 parts by mass The composition of the inorganic antibacterial agent coating solution is as follows.
・ Luna Silver (silver liquid antibacterial agent, manufactured by Antibacterial Kaken Co., Ltd.)

Thereafter, the laminate E is formed in a heating exothermic furnace at 230 ° C. by foaming an unfoamed resin layer containing a foaming agent to form a foamed resin layer, and then embossed to form a textured pattern. And got a wallpaper.
A schematic diagram of the obtained wallpaper is shown in FIG. The wallpaper 100 includes a pattern layer 120, an intermediate layer 130, and a photocatalytic compound 140a on a wallpaper substrate 110 including a backing sheet layer 111, a second non-foamed resin layer 112, a foamed resin layer 113, and a first non-foamed resin layer 114. A visible light type photocatalyst layer 140 and an inorganic antibacterial agent layer 150 containing an inorganic antibacterial agent 150b.

[Example 2]
After producing the laminate C in the same manner as in Example 1, the visible light type photocatalyst coating liquid whose composition was changed as follows was dried on the intermediate layer of the laminate C so that the weight after drying was 1 g / m ^2. To obtain a laminate F. Further, an inorganic antibacterial coating liquid having a composition changed as follows is applied to the entire surface of the laminate F on the visible light photocatalyst layer side so that the weight after drying is 1 g / m ^2. Thus, a laminate G was obtained.
The composition of the visible light type photocatalyst coating liquid is as follows.
-Titanium oxide photocatalyst coating agent (manufactured by Sumitomo Chemical Co., Ltd., trade name: TC-S4115 (with inorganic binder) NV 5 wt%, titanium oxide particle size 100 nm), 100 parts by mass-Inorganic adsorbent (manufactured by Tosoh Corporation, HSZ800 series 890HOA type), 50 parts by mass Matting agent (particles made of melamine and silica, manufactured by Nissan Chemical Industries, Ltd., trade name: Opto beads 3500M, particle size 3.5 μm), 3.5 parts by mass The composition of the antibacterial agent coating solution is as follows.
Lunar Silver (silver-based liquid antibacterial agent, manufactured by Antibacterial Kaken Co., Ltd.), 50 parts by mass Titanium oxide photocatalyst coating agent (manufactured by Sumitomo Chemical Co., Ltd., trade name: TC-S4115 (with inorganic binder) NV 5 wt%, titanium oxide particle size 100 nm), 100 parts by mass. Then, in the heating exothermic furnace at 230 ° C., the foamed resin layer is formed by foaming the unfoamed resin layer containing the foaming agent. Was embossed, and a texture pattern was formed to obtain a wallpaper.
A schematic diagram of the obtained wallpaper is shown in FIG. The wallpaper 200 has a pattern layer 220, an intermediate layer 230, and a photocatalytic compound 240a on a wallpaper substrate 210 including a backing sheet layer 211, a second non-foamed resin layer 212, a foamed resin layer 213, and a first non-foamed resin layer 214. And a visible light photocatalyst layer 240 containing an inorganic adsorbent 240c, and an inorganic antibacterial agent layer 250 containing a photocatalyst compound 250a and an inorganic antibacterial agent 250b.

[Example 3]
After the laminate C was prepared in the same manner as in Example 1, the second intermediate layer coating solution was applied onto the intermediate layer of the laminate C so that the weight after drying was 1 g / m ^2, and the laminate H Got. On the second intermediate layer of the laminate H, a visible light photocatalyst coating liquid similar to that of Example 1 was applied so that the weight after drying was 1 g / m ² to obtain a laminate I. Furthermore, the weight after drying the inorganic antibacterial agent coating liquid similar to that of Example 1 in a mesh pattern so as to cover about 50% of the outermost surface of the laminate I on the visible light photocatalyst side is 0.5 g / m ^2. It sprayed so that it might become, and the laminated body J was obtained.
The composition of the second intermediate layer coating solution is as follows.
-Titanium oxide photocatalyst coating agent (manufactured by Sumitomo Chemical Co., Ltd., trade name: TC-S4115 (with inorganic binder) NV 5 wt%, titanium oxide particle size 100 nm), 100 parts by mass-Inorganic adsorbent (manufactured by Tosoh Corporation, HSZ800 series 890HOA type), 50 parts by mass Matting agent (particles made of melamine and silica, manufactured by Nissan Chemical Industries, Ltd., trade name: Opt beads 3500M, particle size 3.5 μm), 3.5 parts by mass The laminate J is heated in a 230 ° C. heating furnace to foam a non-foamed resin layer containing a foaming agent to form a foamed resin layer, and then embossed to shape a textured pattern, Got a wallpaper.
A schematic diagram of the obtained wallpaper is shown in FIG. The wallpaper 300 is formed on the wallpaper substrate 310 including the backing sheet layer 311, the second non-foamed resin layer 312, the foamed resin layer 313, and the first non-foamed resin layer 314, on the pattern layer 320, the intermediate layer 330, and the photocatalytic compound 360a. And a second intermediate layer 360 containing an inorganic adsorbent 360c, a visible light photocatalyst layer 340 containing a photocatalytic compound 340a, and an inorganic antibacterial agent layer 350 containing an inorganic antibacterial agent 350b.

[Comparative Example 1]
In the heating exothermic furnace at 230 ° C., the laminate D produced in the same manner as in Example 1 is foamed with an unfoamed resin layer containing a foaming agent to form a foamed resin layer, and then embossed, A texture pattern was shaped to obtain a comparative wallpaper.
A schematic diagram of the obtained comparative wallpaper is shown in FIG. The wallpaper 400 for comparison includes a pattern layer 420, an intermediate layer 430, and a wallpaper layer 410 including a backing sheet layer 411, a second non-foamed resin layer 412, a foamed resin layer 413, and a first non-foamed resin layer 414. A visible light photocatalyst layer 440 containing the photocatalyst compound 440a is included. The comparative wallpaper 500 does not have an inorganic antibacterial agent layer.

(2) Wallpaper antibacterial test The wallpaper obtained in Examples 1 to 3 and the comparative wallpaper obtained in Comparative Example 1 were subjected to an antibacterial test as follows.
The test bacteria solution was prepared by suspending the indicator bacteria in the culture solution, and the number of viable bacteria was measured at the same time. A normal broth medium diluted 100 times is used for the culture solution, and three kinds of indicator bacteria, B. subtilis, E. coli and S. aureus, are used. Each was used.
A wallpaper test piece (5 cm × 5 cm) is put in a sterile petri dish, and the above test bacterial solution is sprinkled on it, under the following two culture conditions: Condition 1: No light irradiation, Condition 2: Fluorescent lamp (about 6000 lx) irradiation. Each was statically cultured. After culturing for 12 hours, the seeded test solution was collected and the viable cell count was measured.
In general, the antibacterial effect of a specimen under specific culture conditions appears as a difference between the number of viable cells before culture (the number of initial bacteria) and the number of viable cells after culture. That is, when the number of viable bacteria after cultivation is increased compared to the initial bacterial count, it is determined that the specimen does not have the ability to inhibit bacterial growth (antibacterial effect). If the number of viable cells after culture is substantially equal to the number of the initial bacteria, it is determined that the specimen has a growth inhibitory ability. When the number of viable bacteria after culture is clearly reduced as compared with the initial bacterial count, the specimen is judged to have an antibacterial effect (bactericidal effect).

The evaluation results of Examples 1 to 3 and Comparative Example 1 are shown in the following Table 1 (no light irradiation) and Table 2 (fluorescent lamp irradiation).

100, 200, 300 Wallpaper 400 Comparative wallpaper 110, 210, 310, 410 Wallpaper substrate 111, 211, 311, 411 Backing sheet layer 112, 212, 312, 412 Second non-foamed resin layer 113, 213, 313, 413 Foamed resin layers 114, 214, 314, 414 First non-foamed resin layers 120, 220, 320, 420 Picture pattern layers 130, 230, 330, 430 Intermediate layers 140, 240, 340, 440 Visible light photocatalyst layers 150, 250 , 350 Inorganic antibacterial layer 360 Second intermediate layer

Claims (11)

  Functional wallpaper having an intermediate layer on a wallpaper substrate including a foamed resin layer, and having a visible light photocatalyst layer containing a visible light photocatalyst compound and an inorganic antibacterial agent layer containing an inorganic antibacterial agent on the intermediate layer .   The functional wallpaper according to claim 1, wherein the inorganic antibacterial agent is a silver-based antibacterial agent containing silver.   The functional wallpaper according to claim 1 or 2, wherein the visible light type photocatalyst layer is disposed on the inorganic antibacterial agent layer.   The functional wallpaper according to claim 3, wherein the inorganic antibacterial agent layer has a pattern shape.   The functional wallpaper of Claim 4 whose coverage of the said visible light type photocatalyst layer by the said inorganic antibacterial agent layer is 50% or less.   The functional wallpaper in any one of Claims 1-5 in which the said inorganic antibacterial agent layer contains a visible light type photocatalyst compound further.   The functional wallpaper in any one of Claims 1-6 in which the said intermediate | middle layer contains an inorganic adsorbent.   The functional wallpaper according to claim 1, wherein the visible light type photocatalyst layer further contains an inorganic adsorbent.   The functional wallpaper according to claim 1, further comprising a second intermediate layer containing an inorganic adsorbent and a visible light photocatalytic compound between the intermediate layer and the visible light photocatalyst layer.   The functional wallpaper according to any one of claims 1 to 9, wherein the wallpaper base material further includes a first non-foamed resin layer on an upper surface of the foamed resin layer.   The functional wallpaper according to any one of claims 1 to 10, wherein the wallpaper base material further includes a second non-foamed resin layer on a lower surface of the foamed resin layer.

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