JP5181201B2 - Wallpaper, building material using this wallpaper, and wall covering structure - Google Patents

Description

The present invention is, for example, affixed to a building material such as a wall material or a ceiling material for indoor use in a house, thereby adjusting the humidity and removing odors and harmful gas components with a simple configuration without impairing the appearance of the indoor space. wall paper to obtain aim and detoxification of building materials using a wall paper, and a covering structure of the wall-like member.

  In recent years, a technique has been proposed in which a photocatalyst such as titanium oxide is supported on the surface of a finishing material on the interior wall of a house (see, for example, Patent Document 1 below). A photocatalyst exhibits a strong oxidative decomposition action by receiving ultraviolet rays. As a result, organic matter and the like attached to the surface of the finishing material is decomposed, and contamination of the surface of the finishing material and bacterial growth are prevented. Further, an air purification action such as removal of odors of indoor air (for example, tobacco odor, pet odor and / or garbage odor) and detoxification of harmful gas components (for example, formaldehyde) can be obtained. In many cases, such a photocatalyst is fixed by being finely divided, dispersed and blended in the coating liquid in the form of particles, and coated on the surface of the finishing material.

JP 2004-76494 A

  By the way, for example, interior walls of houses and the like are finished by pasting wallpaper on the surface of a rigid wall-shaped substrate. Here, as the wall-shaped substrate, for example, a porous material having moisture absorption / release performance such as diatomaceous earth, gypsum board, or wood-based material is often used. Such a material lowers the humidity of the indoor space by absorbing and holding the moisture when the room is humid, for example, while increasing the humidity of the indoor space by releasing the held moisture into the room when drying. Work. As a result, the indoor space is adjusted to a substantially constant humidity range, and there is an advantage of providing a comfortable humidity environment for the occupants.

  However, when a paint containing a photocatalyst is applied to such a moisture absorbing / releasing material and cured, the pores on the surface are blocked, and the above moisture absorbing / releasing performance cannot be sufficiently functioned. . In addition, the photocatalyst enters the inside of the porous portion of the moisture absorbing / releasing material and cannot receive sufficient ultraviolet rays, so that the above-described oxidative decomposition action may be insufficient.

  The present invention has been devised in view of the above circumstances, a transparent film body and a photocatalyst carried on the surface of the film body that is not in contact with the wallpaper body. Adhering a cover layer having air permeability and having these moisture permeability limited to a certain range, for example, by being used for an indoor wall of a house, without impairing the appearance of the indoor space, The main object of the present invention is to provide a wallpaper capable of adjusting humidity, removing odors and detoxifying harmful gas components with a simple structure, a building material using this wallpaper, and a covering structure of a wall-like body.

The invention according to claim 1 of the present invention includes a wallpaper body having air permeability and a cover layer bonded to the surface of the wallpaper body and having air permeability, and the cover layer is a surface of the wallpaper body. A transparent film body that is visible from the outside, and a photocatalyst supported on the surface of the film body that is not in contact with the wallpaper body, and the wallpaper body and the cover layer are adhered to each other. Is characterized by being 200 g / m ² · 24 hr or more at a temperature of 40 ° C. and a humidity of 90%.

  The invention according to claim 2 is characterized in that the wallpaper body includes at least one layer of a wallpaper base material and a decorative layer that is bonded to the wallpaper base material and has air permeability. The wallpaper according to claim 1, wherein a cover layer is adhered.

The invention according to claim 3 is the wallpaper according to claim 1 or 2, wherein the moisture permeability of the cover layer is 1000 g / m ² · 24 hr or more at a temperature of 40 ° C. and a humidity of 90%.

According to a fourth aspect of the present invention, the cover layer has a thickness of 10 to 50 μm and has 10,000 to 1,000,000 small holes having a maximum diameter of 0.01 to 1 mm per 1 m ² . Item 4. The wallpaper according to any one of Items 1 to 3.

  The invention according to claim 5 is the wallpaper according to claim 2, wherein the decorative layer is a sheet material of paper type, cloth type, non-woven fabric type or resin type.

  According to a sixth aspect of the present invention, the decorative layer has a thickness of 0.5 to 2.0 mm, and a plurality of concavo-convex patterns having a depth of 0.1 to 1.0 mm are formed on the surface of the cover layer. It is the wallpaper of Claim 2 or 5 currently formed.

  The invention according to claim 7 is a building material characterized in that a wall-like substrate having moisture absorption / release performance is coated with the wallpaper according to any one of claims 1 to 6.

In the invention which concerns on Claim 1, the wallpaper which contains the wallpaper main body which has air permeability, and the cover layer which adhere | attaches on the surface of this wallpaper main body and has air permeability is provided. In such a wallpaper, since the wallpaper body and the cover layer are both air permeable, even if they are attached to a wall-like substrate having moisture absorbing / releasing performance, the moisture absorbing / releasing performance is not impaired. Moreover, the moisture permeability of the wall-shaped substrate is further improved because the moisture permeability when the wallpaper body and the cover layer are bonded is 200 g / m ² · 24 hr or more at a temperature of 40 ° C. and a humidity of 90%. It can be surely demonstrated. Moreover, since the cover layer has transparency that allows the wallpaper body to be seen through, the cover layer does not hinder the visibility of the decorative pattern or the like shown on the wallpaper body. Therefore, deterioration of the appearance can be prevented. Furthermore, since the photocatalyst is fixed to the surface of the film body constituting the cover layer that is not in contact with the wallpaper body, the photocatalyst can surely receive ultraviolet rays, and thus can efficiently exhibit an oxidative decomposition action.

  As described above, the invention according to claim 1 can exhibit the oxidative decomposition action by the photocatalyst with a simple structure without impairing the moisture absorption / release performance of the wallpaper base and the appearance of the decorative layer. Therefore, as in the invention according to claim 7, the building material in which the wall-shaped substrate having moisture absorption / release performance is coated with such wallpaper can prevent surface contamination over a long period of time and The cleaning effect can be exhibited efficiently.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows an enlarged plan view of the wallpaper 1 of the present embodiment, and FIG. 2 shows an AA end view thereof. The wallpaper 1 of this embodiment is used suitably as what coat | covers the surface of building materials, such as a building material, especially indoor wall material or ceiling material, for example. That is, the wallpaper 1 of the present embodiment is preferably arranged so as to face the indoor side of a house or building.

  The wallpaper 1 includes a wallpaper main body 2 having air permeability and a cover layer 3 adhered to the surface 2o of the wallpaper main body 2 and having air permeability. The film body 5 is transparent so that the surface 2o can be seen through from the outside, and the photocatalyst 6 is supported on the surface 5a of the film body 5 that is not in contact with the wallpaper body 2.

  In the present embodiment, the wallpaper main body 2 is composed of a single-layer and sheet-like wallpaper base material 2A and a decorative layer 2B having a back surface 2Bi bonded to the wallpaper base material 2A and having air permeability. The surface 2Bo of the decorative layer 2B forms the surface 2o of the wallpaper body 2.

  The wallpaper base material 2A is, for example, a base material for securing the basic rigidity of the wallpaper 1, and various materials can be used without particular limitation as long as it is a sheet having air permeability. obtain. For example, a paper-based, wood-based, cloth-based or non-woven sheet material (including a composite laminate in which two or more different materials are stacked) is preferably used as the wallpaper substrate 2A. Moreover, as long as it has air permeability, for example, a resin-made sheet material having open cells can be used, and the sheet material is not limited thereto. In the present embodiment, a paper base material 2A is formed by a single sheet of paper-based material, but the wallpaper base material 2A can be formed by laminating two or more layers of sheet materials.

  The thickness of the wallpaper base material 2A is appropriately set according to the strength of the material used. Therefore, it is not particularly limited. In order to improve the durability and workability of the wallpaper base material 2A in a well-balanced manner, the thickness is preferably about 0.5 to 2.0 mm.

  Although not shown, for example, an adhesive layer is provided on the back surface 2Ai of the wallpaper base material 2A to be the back surface 2i of the wallpaper body 2, and a release paper is pasted to cover the adhesive layer. You can also. Such wallpaper is useful for improving the efficiency of on-site wallpaper construction work.

In the present embodiment, the decorative layer 2B has a back surface 2Bi fixed to the wallpaper base material 2A with an adhesive 7 and a surface 2Bo on the opposite side, and the surface 2Bo has the surface of the wallpaper 1 on the surface 2Bo. A cosmetic finish that determines the appearance is applied. The makeup finish is intended to include all finish forms formed on the premise that it is visually recognized from the outside. For example, a flat pattern, a three-dimensional pattern and / or a color pattern are formed by printing or the like. In addition, it is of course possible to have a solid color and plain pattern finish. The wallpaper base material 2A and the decorative layer 2B are made of a material that shrinks when solidified, such as starch paste for wallpaper, or by applying the adhesive 7 very thinly. Bonded so that it is not obstructed.

The decorative layer 2B is also formed of a breathable sheet material so as not to impair the breathability of the wallpaper substrate 2A. Such a material is not particularly limited, and for example, a paper-based, fabric-based or non-woven-based sheet material is suitable. In particular, a resin-based sheet agent containing at least one polymer selected from ethylene-vinyl acetate copolymer, ethylene-acrylic acid ester copolymer, and polyvinyl chloride as a main component is suitable. Further, the decorative layer 2B by blowing a resin coating while exposing a portion of the surface of the wallpaper substrate 2A may be formed. In addition, although the decorative layer 2B of this embodiment is formed by one layer, you may form by laminating | stacking the sheet material of two or more layers.

  The cover layer 3 includes a film body 5 having transparency and air permeability through which the surface 2o of the wallpaper body 2 can be seen from the outside, and a number of particulates carried on the surface 5a of the film body 5. And a photocatalyst 6.

Such a cover layer 3 does not interfere with the appearance (makeup finish) of the decorative layer 2B by including the film body 5 having transparency. Therefore, the interior decoration function as wallpaper 1 is not impaired. Here, the film body 5 is not limited to a completely colorless and transparent material, and may be colored and transparent or semitransparent as long as it can substantially see through the decorative layer 2B .

  Since the surface 5a of the film body 5 of the cover layer 3 carries a large number of particulate photocatalysts 6, when the photocatalyst 6 receives ultraviolet rays, the surface of the film body 5 is strongly oxidized and decomposed. In addition to dirt and bacteria adhering to 5a, malodor and the like can be decomposed into carbon dioxide and water. Thereby, the sterilization and antibacterial action of the surface of the wallpaper 1 can be obtained permanently over a long period of time, and effects such as purification and deodorization of indoor air can be exhibited.

  Furthermore, both the wallpaper body 2 and the cover layer 3 have air permeability. Thereby, it becomes possible to make the room air communicate with the wall-shaped substrate such as a gypsum board having moisture absorption / release performance to which the wallpaper 1 is attached via the wallpaper 1. Therefore, the indoor humidity control function using the moisture absorption / release performance of the wall-shaped substrate is not impaired.

  The cover layer 3 can be made by various methods. For example, as shown in FIG. 3, a coating step S1 for applying a coating liquid L containing particulate photocatalyst 6 directly or via a primer layer (not shown) on the transparent film body 5; A drying step S2 for forming the composite sheet F having the photocatalyst 6 supported on the film body 5 by drying the coating liquid L, and a perforating step S3 for forming a large number of small holes penetrating the composite sheet body F. Can be manufactured.

  As the transparent film body 5, for example, a film mainly composed of polyester, vinyl chloride resin, acrylic resin, polycarbonate, polyimide, polyethylene, polypropylene, or ethylene-vinyl alcohol copolymer (EVOH) is desirable. These provide good workability when providing an uneven pattern such as embossing. The “main component” is defined as a component that occupies at least 50% of all components.

  The photocatalyst 6 is not particularly limited as long as it exhibits the above-mentioned photocatalytic reaction upon receiving light such as ultraviolet rays, and various materials can be used. For example, one or more metal oxides such as titanium dioxide, zinc oxide, tin oxide, lead oxide, ferric oxide, dibismuth trioxide, tungsten trioxide or strontium titanate are suitable as the photocatalyst 6. In particular, titanium dioxide is desirable from the viewpoint of harmless, chemically stable and low cost. As the titanium dioxide, anatase type titanium dioxide, rutile type titanium dioxide, Brooklite type titanium dioxide and the like are known, and anatase type titanium dioxide having high photocatalytic reaction is particularly preferable.

  The particle size of the photocatalyst 6 is not particularly limited, but if the particle size is increased, the transparency of the cover layer 3 tends to be impaired, and conversely if too small, the cost may increase. From such a viewpoint, it is preferable that the photocatalyst 6 has an average particle diameter determined by a dynamic scattering measurement method of preferably 1 to 500 nm, more preferably 3 to 400 nm, and still more preferably 5 to 300 nm.

  The coating liquid L is obtained by mixing the particulate photocatalyst 6 in a solvent. In addition to containing an organic solvent and water, the solvent preferably contains an inorganic binder such as a silane coupling agent in order to enhance adhesion of the photocatalyst 6, for example. Examples of the organic solvent include monohydric lower alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol, polyhydric alcohols such as ethylene glycol and propylene glycol, and their esters such as cellosolve, ethyl acetate, methyl isobutyl ketone, Isobutanol, methyl ethyl ketone, toluene, xylene and the like can be suitably used. Monovalent lower alcohols, particularly isopropyl alcohol and ethanol are preferably used.

  As a preferred embodiment, the coating liquid L desirably contains the photocatalyst 6 in a solid content concentration of 0.2 to 20% by weight, more preferably 5 to 10% by weight. When the blending amount of the photocatalyst 6 is less than 0.2% by weight, a sufficient photocatalytic reaction may not be exhibited, and when it exceeds 20% by weight, the transparency of the cover layer 3 may be impaired.

  The coating step S1 is not particularly limited, and various coating methods such as gravure coating, spray coating, or dip coating can be selected. In particular, it is preferable to use a gravure roll coater as schematically shown in FIG.

  The drying step S2 is desirably performed under conditions of, for example, a heating temperature of 80 to 100 ° C., a drying hot air speed of 10 to 30 m / s, and a drying time of about 20 to 180 seconds. Moreover, in order to suppress the elongation of the film body 5 due to heat during drying, the film body 5 desirably has an elastic modulus of 100 MPa or more in a temperature range of 80 to 100 ° C. Thereby, elongation at the time of drying is reliably suppressed, and as a result, dimensional stability is ensured, and cracking of the particles of the photocatalyst 6 can be effectively suppressed. The film body 5 preferably has a thickness of 10 to 50 μm in order to prevent breakage due to tension or the like when the cover layer 3 is formed.

In the perforating step S3, the roller R1 or R2 having a large number of needle-like members on the surface is pressed against the composite sheet F of the film body 5 and the photocatalyst 6. As a result, as shown in FIGS. 1 and 2, a large number of small holes h that pass therethrough are formed in the cover layer 3. Such a small hole h is desirable in that sufficient air permeability and moisture permeability can be imparted to the cover layer 3. In place of the rotors R1 and R2, drilling may be performed using a press die having a needle-like member and movable up and down. The cover layer 3 of this embodiment has air permeability by forming such small holes h.

The number of the small holes h and the maximum diameter r are not particularly limited. However, when the number of the small holes h is reduced or the maximum diameter thereof is reduced, the air holes formed in the wallpaper body 2 and the small holes h of the cover layer 3 communicate with each other. As a result, when the wallpaper body 2 and the cover layer 3 are bonded, the air permeability as the composite may not be sufficiently obtained. From such a viewpoint, the number of the small holes h is preferably 10,000 or more, more preferably 100,000 or more per 1 m ² . Similarly, the maximum diameter r of the small hole h is preferably 0.01 mm or more, more preferably 0.05 mm or more.

On the other hand, if the maximum diameter r of the small hole h is too large, or if the number of small holes h per 1 m ^{2 of the} cover layer 3 is too large, good air permeability can be easily obtained, but the small hole h is external. , The appearance and durability of the wallpaper 1 may be deteriorated, or the durability of the cover layer 3 may be reduced. From such a viewpoint, the number of the small holes h is desirably 1,000,000 or less, more preferably 500,000 or less per 1 m ² . Similarly, the maximum diameter r of the small hole h is preferably 1 mm or less, more preferably 0.5 mm or less.

  Here, the maximum diameter r of the small hole h is measured as the largest outer diameter of the small hole h sandwiched between two parallel straight lines, as shown in FIG.

  In addition, the small holes h may be dispersedly formed at a random pitch, but as shown in FIG. 1, the small holes h are formed in a grid shape vertically and horizontally at a constant pitch a and b (of course, a = b may be sufficient). It is particularly desirable that it be formed. This is desirable in that the strength of the cover layer 3 can be ensured uniformly and uniform air permeability can be obtained without bias when bonded to the wallpaper body 2.

And the wallpaper 1 is manufactured by adhere | attaching this cover layer 3 on the said surface 2o of the wallpaper main body 2 which adhere | attached the wallpaper base material 2A and the decoration layer 2B previously. Although not particularly limited, considering the workability and the like, the total thickness of the wallpaper 1 is preferably about 0.5 to 2.0 mm.

Further, the wallpaper 1 has a water vapor transmission rate of 200 g / m ² · 24 hr or more under the measurement conditions of a temperature of 40 ° C. and a humidity of 90% in a state where the wallpaper body 2 and the cover layer 3 are bonded to each other. Is preferably set to 300 g / m ² · 24 hr or more, more preferably 400 g / m ² · 24 hr or more.

  Both the wallpaper body 2 and the cover layer 3 have air permeability. However, when these are bonded, the ventilation holes may not be completely matched and the ventilation resistance may be increased. However, in the wallpaper 1 of the present invention, Since the moisture permeability as a composite body of the wallpaper main body 2 and the cover layer 3 is limited, reliable air permeability and moisture permeability can be exhibited. The moisture permeability is measured in accordance with JIS Z0208 “Moisture-permeable packaging material moisture permeability test method (cup method)”.

The cover layer 3 alone preferably has a moisture permeability of 1000 g / m ² · 24 hr or more under the same conditions as described above, that is, under the measurement conditions of a temperature of 40 ° C. and a humidity of 90%. Thereby, the moisture permeability as the above-mentioned composite can be easily exhibited.

  As shown in FIG. 4, such a wallpaper 1 is applied as a surface finishing material on the surface of a wall-shaped substrate 21 made of, for example, diatomaceous earth, gypsum board, or wood-based material having moisture absorption / release performance (humidity control function). By being attached, the covering structure of the wall-like body is provided. Such a wall-like body is used for various applications such as various building materials, more specifically, ceiling materials, wall materials, partition materials, and office partitions. Then, the wall-like body 20 can exert operational effects such as purification of indoor air and prevention of surface contamination by the photocatalyst 6 without impairing the moisture absorption / release performance of the wall-like substrate 21. In addition, the wallpaper 1 can be manufactured by an extremely simple operation of bonding the cover layer 3 to the wallpaper body 2, so that the cost is low and the productivity is excellent.

  FIG. 5 shows a wallpaper 1 according to another embodiment of the present invention. In this embodiment, the decorative layer 2 </ b> B constituting the wallpaper body 2 is exemplified by a plurality of layers. Specifically, the decorative layer 2B includes, for example, a sheet-like inner layer 2Ba bonded to the wallpaper base material 2A and the adhesive 7, and a sheet-like outer layer 2Bb arranged on the outside of the inner layer 2Ba. Consists of. Thus, the decorative layer 2B may be formed as a laminate of a plurality of sheet materials. Although not shown, the wallpaper base material 2A may be formed by laminating a plurality of sheet materials as described above.

  FIG. 6 shows a wallpaper 1 according to another embodiment of the present invention. In this embodiment, an uneven pattern (so-called embossed pattern) is formed on the surface. The concavo-convex pattern can be easily formed by rolling the wallpaper 1 shown in FIG. 2 with, for example, a roll for forming an emboss. Although not particularly limited, the embossing depth d is preferably about 0.1 to 1.0 mm. On the other hand, the thickness of the decorative layer 2B is preferably 0.5 to 2.0 mm.

Moreover, the above-mentioned cover layer 3 is suitably used not only as a constituent material of the wallpaper 1, but also as a covering material for the wall-like body. For example, FIG. 7 shows a partial cross-sectional view of the wall-like body 20 as an example. In the present embodiment, the wall-like body 20 includes the wall-like base 21 made of a wood material having moisture absorption / release performance and a cosmetic finish on the outer surface, and the cover that is bonded to the surface and has air permeability through the small holes h. Layer 3. The cover layer 3 forms the outer surface of the wall-like body 20 on the indoor side. The moisture permeability of the cover layer 3 is also preferably 200 g / m ² · 24 hr or more at a temperature of 40 ° C. and a humidity of 90% in order to ensure air permeability.

  Similarly to the embodiment, the cover layer 3 is in contact with the film body 5 having transparency that allows the surface of the wall-shaped substrate 21 to be seen through from the outside, and the wall-shaped substrate 21 of the film body 5. Since the photocatalyst 6 supported on the surface is not present, the oxidative decomposition action of the photocatalyst 6 can be exhibited with a simple structure without impairing the moisture absorption / release performance and appearance of the wall-shaped substrate 21. The wall-shaped substrate 21 includes not only so-called wall materials but also various building materials that face indoor spaces of houses or buildings, such as ceiling materials and floor materials. In addition, as the wall-shaped substrate 21, diatomaceous earth, gypsum board, a wood-based material, or the like is suitably used as having a moisture absorption / release performance.

  In order to confirm the effects of the present invention, a test piece was prepared by pasting a wallpaper manufactured based on the specifications shown in Table 1 on a wall-shaped substrate, and the following test was performed. The present invention is not limited to the following specific examples.

  As the wall-like substrate of the test piece of each example, “Sawayaka gypsum board” (trade name: manufactured by Chiyodaute Co., Ltd.) having a 10 cm × 10 cm square having an absorption / release property was used. In addition, the wallpaper was adhered to only one surface of the wall-shaped substrate using the starch paste for wallpaper. The other surfaces (back surface and side surfaces) of the wall-shaped substrate were all sealed with aluminum tape. However, the tobacco disintegration test and the acetaldehyde removal test were evaluated using wallpaper alone, without using a wall-like substrate.

  In the absorbency test, the test piece of Comparative Example 1 was composed only of a wall substrate without attaching any wallpaper.

  In the absorbency test, only the wallpaper main body without the cover layer was used as the wallpaper for the test piece of Comparative Example 2.

  Moreover, in the absorbency-release property test, the wallpaper of an Example was manufactured by adhere | attaching a cover layer on the wallpaper main body which consists of a wallpaper base material and a decorative layer. The common specifications of each part are as follows.

[Wallpaper substrate]
Material: Paper quality Thickness: 1.0mm

[Coating layer]
Material: EVA (ethylene vinyl acetate copolymer)
Thickness: 0.5mm

[Cover layer]
Film material: EVOH (Kuraray HF-ME)
Film thickness: 12μm

[Photocatalyst coating solution]
A slurry having an average particle size of 0.3 μm obtained by adding citric acid as a dispersant (0.1 mol to titanium oxide) to titanium oxide P-25 (anatase type) manufactured by Nippon Aerosil Co., Ltd. A), Taki Chemical Co., Ltd. Titanium Oxide Sol M-6 (anatase type, average particle size 20 nm) (B), and Taki Chemical Co., Ltd. Titanium Oxide Sol M-5 (anatase type, average particle size 5 nm) ) (C) and tetraethoxysilane (D) manufactured by Kanto Chemical Co., Ltd. in terms of oxides (TiO ₂ , SiO ₂ ), respectively (B) / ((A) + (B) + (C)) × 100 = 10%, (D) / ((A) + (B) + (C) + (D)) = 20% The mixture was mixed, diluted with water and ethanol, and converted to oxide ( TiO _2, total solids concentration of 8% of SiO _2), 50% ethanol photocatalyst coating liquid obtained . Then, the photocatalyst coating liquid was coated on the film with a gravure roll coater, dried, and then perforated to obtain a cover layer. The roll speed was 50 m / min, the coating amount was 1 g / m ² , and the drying temperature was 80 ° C.

  The test method is as follows.

<Tobacco crab degradation test>
The initial yellowing degree of the test piece was measured by the method described in ASTM D1925. Place the above test piece in a sealed 30cm x 30cm x 30cm container, smoke 1/3 cigarette (JT Mild Seven), take out the test piece after 1 hour, and then irradiate 365nm UV light with a black light at 1mW / cm ² was irradiated for 4 hours. This series of cycles was performed 5 cycles. Thereafter, the yellowing degree was measured again, and the difference from the initial yellowing degree was obtained. The smaller the yellowness difference, the better.

<Acetaldehyde removal test>
A 10 cm × 25 cm wallpaper test piece and a gas having an acetaldehyde gas concentration of 200 ppm were sealed in 10 L of Tedlar bag (trade name: manufactured by Tedlar) and stored in the dark for 24 hours. Next, the test piece kept in the Tedlar bag was irradiated with a white fluorescent lamp of 6000 Lx for 24 hours, and then the acetaldehyde concentration was measured. The smaller the gas concentration, the better.

<Moisture absorption / release test>
The test piece was allowed to stand for 24 hours at 25 ° C. and 50% RH, and then its weight was measured (weight A). Thereafter, the same test piece was allowed to stand for 24 hours under the conditions of 25 ° C. and 90% RH, and then its weight was measured (weight B). Furthermore, after the same test piece was allowed to stand for 24 hours under the conditions of 25 ° C. and 50% RH, the weight was measured (weight C). And the amount of moisture absorption and the amount of moisture release were computed by the following formula. The larger the value, the better the quality of absorption and release.
Moisture absorption = (weight B−weight A) / test area Moisture release = (weight B−weight C) / test area Table 1 shows the test results.

  As a result of the test, it was confirmed that all of the test pieces of Examples exhibited significantly the air purification effect and the surface yellowing prevention effect without impairing the absorption / release performance of the wall-shaped substrate.

It is a top view of the wallpaper 1 which shows embodiment of this invention. It is the AA end elevation. It is the schematic which shows the manufacturing process of a cover layer. It is sectional drawing of the wall-shaped body which shows the coating structure of embodiment of this invention. It is sectional drawing of the wallpaper which shows other embodiment of this invention. It is sectional drawing of the wallpaper which shows other embodiment of this invention. It is sectional drawing of the wall-shaped body which shows the coating structure of other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wallpaper 2 Wallpaper main body 2A Wallpaper base material 2B Cosmetic layer 3 Cover layer 5 Film body 6 Photocatalyst 20 Wall-shaped body 21 Wall-shaped base | substrate h Small hole

Claims (7)

A breathable wallpaper body;
A cover layer that is bonded to the surface of the wallpaper body and has air permeability, and the cover layer includes a transparent film body that allows the surface of the wallpaper body to be visually recognized from the outside, and the wallpaper of the film body. Having a photocatalyst supported on a surface not in contact with the body,
A wallpaper having a moisture permeability of 200 g / m ² · 24 hr or more at a temperature of 40 ° C. and a humidity of 90% when the wallpaper body and the cover layer are bonded. The wallpaper body includes at least one layer of a wallpaper base material, and a decorative layer that is bonded to the wallpaper base material and has air permeability.
The wallpaper according to claim 1, wherein the cover layer is adhered to a surface of the decorative layer. The wallpaper according to claim 1 or 2, wherein the cover layer has a moisture permeability of 1000 g / m ² · 24 hr or more at a temperature of 40 ° C and a humidity of 90%. 4. The cover layer according to claim 1, wherein the cover layer has a thickness of 10 to 50 μm and has 10,000 to 1,000,000 small holes having a maximum diameter of 0.01 to 1 mm per 1 m ^2. Wallpaper.   The wallpaper according to claim 2, wherein the decorative layer is a paper-based, cloth-based, non-woven fabric-based, or resin-based sheet material.   6. The decorative layer has a thickness of 0.5 to 2.0 mm, and a plurality of uneven patterns having a depth of 0.1 to 1.0 mm are formed on the surface of the cover layer. Wallpaper as described in.   A building material comprising a wall substrate having moisture absorption / release performance coated with the wallpaper according to any one of claims 1 to 6.

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