JP6200567B2 - Veneer - Google Patents

Description

The present invention relates to a decorative board.

Conventionally, a decorative board provided with functionalities such as antifouling properties and antibacterial properties by adding or applying a functional substance such as a photocatalyst to a decorative board such as a melamine decorative board has been provided.

Patent Document 1 proposes a functional building material that is coated with a resin coating film containing a functional material having functions such as antibacterial and antiviral properties, and the functional material is fixed near the surface. ing.

Patent Document 2 proposes a manufacturing method for obtaining an antibacterial polyester decorative board by applying an unsaturated polyester resin to which an antibacterial agent made of a calcium ceramic fired powder having an antibacterial metal supported on the surface of paper is applied. Has been.
Patent Document 3 discloses a decorative board in which a photocatalyst-supporting porous body in which titanium oxide is supported on the surface of an aluminum hydroxide powder is fixed to the surface of the decorative board.

JP 2008-80210 A Japanese Patent Application Laid-Open No. 07-304619 JP 2002-285691 A Japanese Patent Laid-Open No. 04-307065

FIG. 4 is a schematic cross-sectional view schematically showing a conventional decorative board (for example, Patent Document 4).
In the decorative board 3, a functional substance 17 such as a photocatalyst is fixed to the surface resin layer 12.

In the decorative board 3 shown in FIG. 4, the surface layer resin of the decorative board is irradiated with ultraviolet rays after the construction, thereby causing a problem that the antibacterial and antiviral functions deteriorate over time. The cause of this is not clear, but it is presumed that the surface resin layer is deteriorated by ultraviolet rays, and the photocatalyst is dropped together with the surface resin.

In addition, a functional substance may be added or applied to the surface layer of the decorative board. In such a case, the functional substance is buried in the surface resin layer of the surface layer, and there are few exposed parts on the surface layer. There was a problem that could not be expressed. Furthermore, the decorative board is required to have high antibacterial and antiviral properties corresponding to a virus inactivity of 99.9% or more (the concentration of the virus not inactivated against E. coli is 1/1000 or less). In some cases, there is also a problem that the functionality cannot be fully expressed.
Further, there is a method of supporting the photocatalyst on the surface of aluminum hydroxide and fixing it to the decorative plate surface as in Patent Document 3 so that the photocatalyst is not buried in the surface resin layer. The amount of titanium supported was 0.45% by weight, and the Ti / Al ratio calculated from the molar ratio with 99.58% aluminum hydroxide was 0.45 / 79.87 / (99.55 × 0.9958). ) /77.98=0.0044, and even when such a decorative plate is diverted as an antiviral decorative plate, there is a problem that the antiviral function cannot be sufficiently exhibited.

The present invention has been made in view of such problems, and prevents the deterioration of the surface resin layer made of melamine resin or the like, has no deterioration in antibacterial and antiviral functions due to deterioration over time, and has excellent functionality. The purpose is to provide. In particular, an object is to provide a decorative board having excellent antibacterial and antiviral properties.

The decorative board of the present invention includes a substrate, a surface resin layer laminated on one or both surfaces of the substrate, aluminum oxide-containing particles exposed on the surface resin layer, and the aluminum oxide-containing particles. And a titania-containing photocatalyst supported on the exposed surface, wherein the molar ratio of Ti / Al on the surface of the surface resin layer is 0.5 to 1.5.

The decorative board of the present invention has aluminum oxide-containing particles that are exposed and arranged on the surface resin layer, and a titania-containing photocatalyst supported on the exposed surface of the aluminum oxide-containing particles, and the surface of the surface resin layer Since the Ti / Al molar ratio in the range is 0.5 to 1.5, it has excellent antibacterial and antiviral properties while being excellent in weather resistance.
In the decorative board of the present invention, since the Ti / Al molar ratio on the surface of the surface resin layer is 1.5 or less, the surface of the aluminum oxide-containing particles is not completely covered with the titania-containing photocatalyst, and the surface of the decorative board is The existing bacteria and viruses have an action of being attracted to the aluminum oxide-containing particles, and have excellent antibacterial and antiviral properties while being excellent in weather resistance. In addition, since the refractive index of titania is larger than that of aluminum oxide, if the Ti / Al molar ratio exceeds 1.5, the light transmittance of the decorative plate decreases, and the decorative plate tends to become cloudy. May affect the design of the.
When the Ti / Al molar ratio on the surface of the surface resin layer is less than 0.5, the amount of titania-containing photocatalyst is small, and the weather resistance is not sufficient, so that antibacterial and antiviral properties will deteriorate with time. .

In addition, the molar ratio of Ti / Al on the surface of the surface resin layer in the decorative board of the present invention is to conduct elemental analysis of the surface resin layer using a scanning electron microscope and energy dispersive spectroscopy (also referred to as SEM / EDX). It can ask for.

In the decorative board of the present invention, it is desirable that the isoelectric point of the aluminum oxide-containing particles is higher than the isoelectric point of the titania-containing photocatalyst. The isoelectric point here means that when the concentration of hydrogen ions in the solution is changed, the positive and negative charges of the particles that become the solute become zero as a whole, and the whole particle does not move even when an electric field is applied. Is the hydrogen ion exponent when the average charge is 0, and the value is expressed as pH. This isoelectric point is a value defined by the substance, and as an example, the isoelectric point of the titania-containing photocatalyst is often pH 5-6, whereas the aluminum oxide-containing particles are of the titania-containing photocatalyst, etc. It is desirable to use those having an isoelectric point higher than the electric point, and it is more desirable that the isoelectric point of the aluminum oxide-containing particles is pH 7 or higher. The isoelectric point can be measured by electrophoresis (JIS R1638).

In the decorative board of the present invention, as components other than aluminum oxide constituting the aluminum oxide-containing particles, cerium, zirconium, strontium, silicon, iron, cobalt, copper, chromium, nickel, tin, cadmium, magnesium, manganese, tungsten, Examples thereof include vanadium and yttrium, and these components may be metals, oxides, hydroxides, hydrates, and the like, and may be combined with aluminum oxide. Regarding the isoelectric point, the isoelectric point of aluminum oxide (Al ₂ O ₃ ) is pH: 7.4 to 9.2, the isoelectric point of boehmite (AlOOH) is pH 7.7 to 9.4, and cadmium. The isoelectric point of hydroxide (Cd (OH) ₂ ) is pH 10.5 or higher, the isoelectric point of cadmium oxide (CdO) is pH 7.7, and the isoelectric point of iron hydrate (Fe (OH) ₂ ). The point is pH 12, the isoelectric point of iron oxide (Fe ₃ O ₄ ) is pH 12, the isoelectric point of copper oxide (CuO) is pH 9.5, and the isoelectric point of copper hydrate (Cu (OH) ₂ ) The point is pH 7.7. It is desirable that these components are combined and the isoelectric point of the aluminum oxide-containing particles is higher than the isoelectric point of the titania-containing photocatalyst.

The aluminum oxide-containing particles have an effect of easily attracting bacteria and viruses. In the first place, since bacteria and viruses contain proteins and fats, they are anionic substances, and the anionic substances have the property of being attracted to the opposite cation substance. In other words, the bacteria and viruses present on the surface layer of the decorative board are attracted to the aluminum oxide-containing particles, and the titania-containing photocatalyst supported on the aluminum oxide-containing particles can reduce the bacteria and viruses. Will not proliferate, making it easier to obtain antibacterial and antiviral effects. In the case of particles that are not aluminum oxide-containing particles, the bacteria and viruses present on the surface layer of the decorative board are less likely to come into contact with the titania-containing photocatalyst, so that the bacteria and viruses remain or multiply, making it difficult to obtain antibacterial and antiviral effects. is there.

In addition, the aluminum oxide-containing particles have a property of easily supporting titania-containing photocatalysts at regular intervals. When the titania-containing photocatalyst is supported on particles that are not aluminum oxide-containing particles, the interval between the titania-containing photocatalysts tends to be narrow. For this reason, the contact frequency between the fungus or virus and the titania-containing photocatalyst decreases, and the expected action of reducing the fungus or virus is not exhibited. As a result, it takes time to reduce the bacteria and viruses, and the antibacterial and antiviral effects are hardly exhibited. On the other hand, since the aluminum oxide-containing particles used in the present invention are carried at regular intervals, there is no decrease in the contact frequency between the bacteria and viruses and the titania-containing photocatalyst, and the bacteria and viruses are reduced at a desired time, Antibacterial and antiviral effects are easily manifested. As described above, the aluminum oxide-containing particles have an effect of causing the titania-containing photocatalyst to be supported at regular intervals and attracting bacteria and viruses, thereby improving antibacterial and antiviral effects. When bacteria and viruses come into contact with the titania-containing photocatalyst, the titania-containing photocatalyst can completely decompose or partially damage the bacteria and viruses, so that the bacteria and viruses can be reduced.
The above-described effects can be obtained by supporting a titania-containing photocatalyst on aluminum oxide-containing particles.

In the decorative board of the present invention, the aluminum oxide-containing particles are desirably particles made of either alumina or strontium aluminate.
Alumina is most easily used among the aluminum oxide-containing particles, and can efficiently use the above-described action of reducing bacteria and viruses. In addition, since strontium aluminate has a phosphorescent action, it can sustain the action of reducing bacteria and viruses for a long time even in an environment without light.

In the decorative board of the present invention, the average particle diameter of the aluminum oxide-containing particles is preferably 0.1 μm to 55 μm.

In the decorative board of the present invention, it is desirable that the aluminum oxide-containing particles are exposed and present at an area ratio of 5 to 30% with respect to the surface resin layer surface.
When the aluminum oxide-containing particles are exposed at an area ratio of 5% or more with respect to the surface resin layer surface, the titania-containing photocatalyst can be sufficiently supported, so that the effect of reducing bacteria and viruses is sufficiently exerted. Can be made. In addition, when the aluminum oxide-containing particles are exposed at an area ratio of 30% or less with respect to the surface resin layer surface, the aluminum oxide-containing particles carrying the titania-containing photocatalyst are firmly bonded to the surface resin layer and hardly fall off. Therefore, the effect | action which reduces a microbe and a virus can fully be continued.

In the decorative board of the present invention, the titania-containing photocatalyst is preferably a visible light responsive photocatalyst.

In the decorative board of the present invention, the visible light responsive photocatalyst is a platinum-supported titania catalyst, a copper-supported titania catalyst, an iron-supported titania catalyst, a nitrogen-doped titania catalyst, a sulfur-doped titania catalyst, or a carbon-doped titania catalyst. desirable. In particular, the isoelectric point of the visible light responsive photocatalyst is preferably pH 5-6.

In the decorative board of the present invention, the surface resin layer preferably contains a silicone resin and / or a silane coupling agent.

In the decorative board of the present invention, it is desirable to have a dried product of silica sol on the surface layer of the aluminum oxide-containing particles. This is because the fixing of the titania-containing photocatalyst can be reinforced.

In the decorative board of the present invention, the aluminum oxide-containing particles are buried and fixed so as to be exposed from the surface resin layer, and the titania-containing photocatalyst is exposed to the surface resin layer so as not to directly contact the aluminum oxide-containing particles. It is preferably carried on the surface.
When the aluminum oxide-containing particles are buried and fixed so as to be exposed from the surface resin layer, and the titania-containing photocatalyst is supported on the exposed surface of the aluminum oxide-containing particles so as not to be directly on the surface resin layer, the titania-containing photocatalyst It is possible to prevent deterioration of the surface resin layer due to, and to prevent the titania-containing photocatalyst from dropping off due to discoloration of the surface resin layer, deterioration of the surface resin layer, or the like.

In the decorative board of the present invention, the aluminum oxide-containing particles can absorb ultraviolet rays to prevent resin deterioration, and the photocatalyst and aluminum oxide-containing particles from the surface resin layer are prevented from falling off. Antiviral function does not deteriorate. In the decorative board of the present invention, the titania-containing photocatalyst is supported on the exposed surface of the aluminum oxide-containing particles and does not directly contact the surface resin layer. In other words, a part of the aluminum oxide-containing particles are buried and fixed so as to be exposed from the surface resin layer, and the photocatalyst is selectively applied to the exposed surface of the aluminum oxide-containing particles so as not to directly contact the surface resin layer. It is carried. For this reason, deterioration of the surface resin layer due to the titania-containing photocatalyst can be prevented, and dropping of the titania-containing photocatalyst due to discoloration of the surface resin layer, deterioration of the surface resin layer, or the like can be prevented. Further, in the present invention, since the titania-containing photocatalyst is not embedded in the surface resin layer and the titania-containing photocatalyst is exposed on the surface of the decorative plate, the original functions as a photocatalyst such as antibacterial and antiviral properties And the effect can be maintained for a long time.

FIG. 1 is a schematic cross-sectional view schematically showing a decorative board according to an embodiment of the present invention. FIG. 2 is an explanatory view showing an area part that is a basis for calculating the area ratio of the exposed part of the aluminum oxide-containing particles constituting the decorative board of the present invention. FIG. 3A is a schematic cross-sectional view schematically showing a decorative board according to one embodiment of the present invention, and FIG. 3B schematically shows a decorative board according to another embodiment of the present invention. It is a schematic sectional drawing shown in FIG. FIG. 4 is a schematic cross-sectional view schematically showing a conventional decorative board.

Hereinafter, the decorative board of the present invention will be described in detail.
FIG. 1 is a schematic cross-sectional view schematically showing a decorative board according to an embodiment of the present invention.

The decorative board 1 of the present invention has a substrate (not shown) and a surface resin layer 12 made of melamine resin or the like laminated on the surface of the substrate, and the aluminum oxide-containing particles 13 are exposed on the surface resin layer 12. The titania-containing photocatalyst 14 is supported on the exposed surface of the aluminum oxide-containing particles 13. In other words, the aluminum oxide-containing particles 13 are buried and fixed so as to be exposed from the surface resin layer 12, and the titania-containing photocatalyst 14 is not exposed to the surface resin layer 12 directly on the exposed surface of the aluminum oxide-containing particles 13. It is supported.

The board | substrate used for the decorative board of this invention is not specifically limited, Incombustible base materials, such as a core paper and a magnesia cement generally used for a decorative board, etc. can be used. The core paper may be a single core or a laminate in which a plurality of core papers are stacked. The number of core papers is not particularly limited, but can be 1 to 20 sheets. As the core paper, for example, aluminum hydroxide paper can be used. The core paper can be impregnated with a phenol resin. Moreover, a core paper and a magnesia cement incombustible base material can be laminated to form a substrate.

The magnesia cement incombustible base material can be used as a substrate by using it alone or by laminating it at the center of the core paper. The magnesia cement incombustible plate is manufactured by mixing magnesium oxide (MgO) and magnesium chloride (MgCl ₂ ), adding aggregate and water, kneading, and forming into a plate shape. As the aggregate, inorganic fibers such as rock wool and glass wool, and organic fibers such as wood chips and pulp can be used. Moreover, in order to raise the intensity | strength of a magnesia cement incombustible board, the glass fiber layer formed in mesh shape etc. can be provided as an intermediate | middle layer.

The method for forming the surface resin layer on the substrate surface composed of a plurality of or a single core paper and / or magnesia cement incombustible base material is not particularly limited, and can be performed by a general method. For example, a method of laminating melamine resin impregnated paper on one side or both sides of the substrate and hot pressing can be used. If the said method is used, the melamine resin of a melamine resin impregnation paper will osmose | permeate core paper, a curing reaction will advance there, and the adhesive force of the melamine resin impregnation paper with respect to a core paper will express.
The resin that can be used for the surface resin layer constituting the decorative board of the present invention includes melamine resin, diallyl phthalate (DAP) resin, polyester resin, olefin resin, vinyl chloride resin, acrylic resin, epoxy resin, urethane resin. , Phenol resin, silicone resin, guanamine resin and the like. In these, it is desirable to use a melamine resin.

Melamine resin is a resin with improved dimensional stability and toughness without impairing optical and visual properties such as translucency. As the melamine resin, known resins can be adopted as long as they are resins having melamine and its derivatives as monomers. The melamine resin may be a resin composed of a single monomer or a copolymer composed of a plurality of monomers. Examples of the melamine derivative include derivatives having a functional group such as an alkoxymethyl group such as an imino group, a methylol group, a methoxymethyl group, or a butoxymethyl group. Further, a compound obtained by reacting a lower alcohol with a melamine derivative having a methylol group and partially or completely etherified can be used as a monomer. Monomethylol melamine, dimethylol melamine, trimethylol melamine, tetramethylol melamine, pentamethylol melamine, hexamethylol melamine and other derivatives having a methylol group (hereinafter referred to as “methylolated melamine”) are copolymerized with melamine as a crosslinking agent. Can be used.

The melamine resin-impregnated paper is produced by impregnating a melamine resin with a predetermined impregnation rate in a pattern paper, and then heating and drying. The pattern paper can be impregnated with the melamine resin by immersing the pattern paper in a melamine resin-containing solution using, for example, an aqueous formaldehyde solution as a solvent. Further, in order to impart bending workability to the melamine resin-impregnated paper, it is possible to impregnate a solution containing a plasticizer together with the melamine resin. As the plasticizer, for example, ε-caprolactam, acetoguanamine, p-toluenesulfonic acid amide, urea and the like can be used. For example, titanium paper is used as the pattern paper. The basis weight of the pattern paper can be set to 80 to 150 g / m ² in consideration of the thickness and weight of the pattern paper. The temperature for heating and drying can be set to 100 to 150 ° C. in order to firmly fix the melamine resin to the pattern paper.

The aluminum oxide-containing particles constituting the decorative board of the present invention are not particularly limited as long as the particles have an isoelectric point higher than that of the titania-containing photocatalyst and can support the titania-containing photocatalyst. Alternatively, it is desirable to use particles made of either strontium aluminate.

In the decorative board of the present invention, the average particle diameter of the aluminum oxide-containing particles is preferably 0.1 to 55 μm, and more preferably 0.5 to 5 μm. When the average particle diameter of the aluminum oxide-containing particles is less than 0.1 μm, the aluminum oxide-containing particles tend to be embedded in the surface resin layer, and the titania-containing photocatalyst tends to be less likely to be supported on the aluminum oxide-containing particles. When the average particle diameter of the particles exceeds 55 μm, the aluminum oxide-containing particles fall off or irregularities are formed on the surface resin layer, which tends to cause defects in the appearance and design of the decorative board. When the average particle diameter of the aluminum oxide-containing particles is 0.5 to 5 μm, the functionality as a titania-containing photocatalyst is exhibited, and there is no problem in the appearance and design of the decorative board.

In the decorative board of the present invention, it is desirable that the aluminum oxide-containing particles are exposed and present at an area ratio of 5 to 30% with respect to the surface resin layer surface.
When the aluminum oxide-containing particles are exposed at an area ratio of 5% or more with respect to the surface resin layer surface, the titania-containing photocatalyst can be sufficiently supported, so that the effect of reducing bacteria and viruses is sufficiently exerted. Can be made. In addition, when the aluminum oxide-containing particles are exposed at an area ratio of 30% or less with respect to the surface resin layer surface, the aluminum oxide-containing particles carrying the titania-containing photocatalyst are firmly bonded to the surface resin layer and hardly fall off. Therefore, the effect | action which reduces a microbe and a virus can fully be continued.
FIG. 2 is an explanatory view showing an area part that is a basis for calculating the area ratio of the exposed part of the aluminum oxide-containing particles constituting the decorative board of the present invention.
The area ratio in the decorative board of the present invention means the ratio of the total surface area B of the surface resin layer on which the aluminum oxide-containing particles 13 are exposed to the surface area A of the entire surface resin layer in FIG. . If the aluminum oxide-containing particles are exposed to an area ratio of less than 5% with respect to the surface resin layer surface, the functionality of the titania-containing photocatalyst tends to be insufficient.

In the decorative board of the present invention, the molar ratio of Ti / Al on the surface of the surface resin layer is 0.5 or more, and preferably 0.6 or more.
When the Ti / Al molar ratio on the surface of the surface resin layer is less than 0.5, the amount of titania-containing photocatalyst is small, and the weather resistance is not sufficient, so that antibacterial and antiviral properties will deteriorate with time. Sometimes.

In the decorative board of the present invention, the titania-containing photocatalyst is preferably a functional material having functions such as antibacterial properties, antiviral properties, antiallergenic properties, and deodorizing properties.

In the decorative board of the present invention, the titania-containing photocatalyst is preferably a visible light responsive photocatalyst.

In the decorative plate of the present invention, the visible light responsive photocatalyst is preferably a platinum-supported titania catalyst, a copper-supported titania catalyst, an iron-supported titania catalyst, a nitrogen-doped titania catalyst, a sulfur-doped titania catalyst, or a carbon-doped titania catalyst. More preferably, it is a copper-supported titania catalyst.
Examples of the copper-supported titania catalyst include anatase-type titanium oxide containing copper in a range of CuO / TiO ₂ (weight% ratio) = 1.0 to 3.5 described in JP-A-2006-232729. Photocatalyst composition in which cuprous oxide (copper oxide (I): Cu ₂ O) and titanium oxide described in Japanese Unexamined Patent Publication No. 2012-210557 are combined, and monovalent copper described in Japanese Patent Application Laid-Open No. 2013-166705 Titanium oxide carrying a mixture containing a compound and a divalent copper compound on the surface, and copper containing titanium oxide containing crystalline rutile-type titanium oxide and divalent copper compound described in International Publication No. 2013/094573 And titanium-containing compositions.

In the decorative board of the present invention, the surface resin layer may contain a silicone resin and / or a silane coupling agent. As the silicone resin, for example, a silicone resin, a modified silicone oil, or the like can be used. As the modified silicone oil, a silicone oil having one or more functional groups in the molecule can be used. The position at which the functional group is introduced is not particularly limited, and the functional group may be introduced at any position of one end, both ends or side chains of the polysiloxane main chain. Moreover, as a functional group, a hydroxyl group, an amino group, a methoxy group, a hydrazino group, an epoxy group, a methacryl group, a carboxyl group, a carbinol group etc. can be introduce | transduced, for example.

As the silane coupling agent, for example, those having a functional group such as vinyl group, propenyl group, butadienyl group, styryl group, acryloyl group, methacryloxy group, amino group, mercapto group, and isocyanate group are desirable. Examples of the silane coupling agent include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, allyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4 -Epoxycyclohexyl) ethyltrimethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane , 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, diallyldimethylsilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, etc. It is.

In the decorative board of the present invention, it is desirable that the surface layer of the aluminum oxide-containing particles has a dried silica sol. After the silica sol is attached to the surface layer of the aluminum oxide-containing particles, the titania-containing photocatalyst is supported and dried, thereby fixing the titania-containing photocatalyst with a dried silica sol and fixing the titania-containing photocatalyst more firmly. Because it can.

Next, the manufacturing method of the decorative board of this invention is demonstrated.
First, a surface resin layer is formed on a substrate surface made of a plurality of or a single core paper and / or a magnesia cement incombustible base material. Since the said board | substrate, its manufacturing method, and the said surface layer resin layer were demonstrated in description of the decorative board of this invention, it abbreviate | omits here.

As described in the decorative board of the present invention, the method of forming the surface resin layer on the substrate surface is not particularly limited and can be performed by a general method. As a specific method for forming the surface resin layer, for example, a lamination step of laminating a resin-impregnated paper such as a melamine resin on one or both sides of a substrate made of a core paper laminate, and a resin-impregnated paper such as a melamine resin are laminated. And a method including a hot-pressure forming step of hot-pressing the formed substrate. If the said method is used, the melamine resin of a melamine resin impregnation paper will osmose | permeate core paper, a curing reaction will advance there, and the adhesive force of the melamine resin impregnation paper with respect to a core paper will express.

As a heating condition at the time of hot pressing, the temperature of the decorative board can be 125 to 150 ° C., and as a pressing condition, 1.96 to 9.80 MPa (20 to 100 kg / cm ² ). Can do. When the temperature is less than 125 ° C. or when the pressure is less than 1.96 MPa, the adhesion of the resin-impregnated paper to the substrate is insufficient, and peeling tends to occur. On the other hand, when the temperature exceeds 150 ° C. or when the pressure exceeds 9.80 MPa, cracks may occur.

As a method for fixing the aluminum oxide-containing particles to the surface resin layer surface having the surface resin layer on the substrate, for example, a method of spraying a spray liquid containing aluminum oxide-containing particles on the surface resin layer surface, drying and then thermocompression bonding Can be taken. Also, after roughening the surface of the resin film and supporting the aluminum oxide-containing particles on the roughened surface, the resin film is laminated so that the support surface of the aluminum oxide-containing particles is in contact with a resin-impregnated paper such as a melamine resin, It is desirable to transfer the aluminum oxide-containing particles to the surface resin layer by removing the resin film after heating and pressing to cure the resin. The surface of the resin film is desirably roughened by at least one method selected from corona discharge, sandblasting, and scratch treatment.
The roughened surface of the resin film desirably has an arithmetic average roughness (Ra) based on JIS B 0601 of 0.05 to 50 μm, and preferably 0.1 to 10 μm. The resin film is preferably at least one material selected from polyethylene terephthalate, polypropylene, and polyethylene. By the above method, the aluminum oxide-containing particles can be exposed and fixed on the resin surface.

After the above step, the titania-containing photocatalyst can be supported on the exposed surface of the aluminum oxide-containing particles by immersing the substrate on which the aluminum oxide-containing particles are disposed in a solution containing the titania-containing photocatalyst. The titania-containing photocatalyst may be supported on the exposed surface of the aluminum oxide-containing particles by applying a solution containing the titania-containing photocatalyst onto the substrate on which the aluminum oxide-containing particles are arranged.

In the method for producing a decorative board according to the present invention, when the aluminum oxide-containing particles are thermocompression bonded to the surface resin layer surface, a separation layer made of polyethylene terephthalate (PET) is provided between the aluminum oxide-containing particle spray surface and the thermocompression press surface. A shape cushion material may be interposed. This can prevent the aluminum oxide-containing particles from being buried in the surface resin layer, and can be exposed and fixed on the surface of the surface resin layer.

As another production method of the decorative board of the present invention, a spray liquid containing aluminum oxide-containing particles is sprayed on the transfer film, and then the aluminum oxide-containing particle adhesion surface of the transfer film is applied to the resin surface of the substrate having the surface resin layer. A method of thermally transferring aluminum oxide-containing particles so as to face each other is mentioned.

When the surface resin layer contains a silicone resin and / or silane coupling agent, the silicone resin and / or the surface resin layer is added to the surface resin layer by including the silicone resin and / or silane coupling agent in the melamine resin solution. A method of impregnating with a silane coupling agent can be used.

FIG. 3A is a schematic cross-sectional view schematically showing a decorative board according to one embodiment of the present invention, and FIG. 3B schematically shows a decorative board according to another embodiment of the present invention. It is a schematic sectional drawing shown in FIG.
When the surface resin layer contains a silicone resin and / or a silane coupling agent, water repellency can be imparted to the surface of the melamine resin or the like. When the titania-containing photocatalyst is supported on the aluminum oxide-containing particles, as schematically shown in FIG. 3 (a), when the surface resin layer 12 does not contain a silicone resin and a silane coupling agent, an aluminum oxide-containing The titania-containing photocatalyst 14 may adhere not only to the surface of the particle 13 but also to the surface resin layer surface 15. On the other hand, as schematically shown in FIG. 3B, when the surface resin layer 12 contains a silicone resin and / or a silane coupling agent, the surface layer contains a silicone resin and / or a silane coupling agent. Due to the water repellency of the resin layer surface 16, the titania-containing photocatalyst 14 avoids the surface of the surface resin layer 12 and adheres as much as possible to the surface of the aluminum oxide-containing particles 13 and directly contacts the surface of the surface resin layer 12. The amount of titania-containing photocatalyst 14 can be further reduced. Moreover, when the surface resin layer contains a silane coupling agent, it is possible to impart curability to the melamine resin and the like, and to prevent the aluminum oxide-containing particles from being buried in the surface resin layer when thermocompression bonding is performed. it can.

By containing a silicone resin and / or a silane coupling agent in the surface resin layer, the aluminum oxide-containing particles can be immobilized without being buried, and the titania-containing photocatalyst is less likely to adhere to the surface resin layer. . Specifically, even if the titania-containing photocatalyst that becomes excessive during the process adheres to the surface resin layer, it can be easily removed after the cleaning process. Furthermore, contaminated water containing bacteria, viruses, and the like is easily attracted to hydrophilic aluminum oxide-containing particles and titania-containing photocatalysts, and functionality is easily exhibited. In particular, when a melamine resin is used for the surface resin layer, it is easy to obtain the above actions and effects.

Furthermore, in the method for producing a decorative board of the present invention, it is desirable to attach silica sol to the surface layer of the aluminum oxide-containing particles. This is because the fixing of the titania-containing photocatalyst can be reinforced.
Further, in the method for producing a decorative board of the present invention, a photocatalyst can be bonded to the surface layer of the aluminum oxide-containing particles through an inorganic binder such as silica sol, and a mixed liquid of the photocatalyst and the inorganic binder is sprayed on the surface. After drying and curing the inorganic binder, a photocatalyst adhering to the surface resin layer other than the aluminum oxide-containing particles can be removed by spraying a cleaning liquid such as alcohol. Since the photocatalyst and the inorganic binder do not adhere to the resin surface, they can be easily removed with alcohol or the like. Alternatively, the photocatalyst may be wiped off with a cloth soaked with alcohol.

Example 1
(Primary melamine impregnation process)
A paper roll having a thickness of 0.2 to 0.3 mm was immersed in a solution containing a melamine resin. The roll paper was impregnated with melamine resin by passing the roll paper while being immersed in the solution so that the temperature of the solution was 20 ° C. and the immersion time was 2 minutes. The moving speed of the roll paper was 10 to 20 cm / second.
(Drying process)
The roll paper that passed through the melamine solution was dried by a dryer (ESPEC, OVEN PH-201) so that the temperature was 100 ° C. and the drying time was 30 seconds.

(Secondary melamine impregnation process)
The paper roll which passed through the drying process was immersed in a solution made of melamine resin. The paper roll was impregnated with the melamine resin by passing the roll paper while being immersed in the solution so that the temperature of the solution was 20 ° C. and the immersion time was 30 minutes. The moving speed of the roll paper was 10 to 20 cm / second.
(Drying / cutting process)
The roll paper that passed through the melamine solution was dried by a dryer (ESPEC, OVEN PH-201) so that the temperature was 100 ° C. and the drying time was 2 hours. After drying, it was cut into 910 mm × 1820 mm.

(Alumina particle spray process)
A spray solution comprising γ-alumina particles having an average particle size of 0.5 μm and ethanol was prepared. The spray liquid was filled into the spray at room temperature and sprayed on the cut melamine resin-impregnated paper.
(Drying process)
The melamine resin-impregnated paper sprayed with alumina particles was dried by a dryer (ESPEC, OVEN PH-201) so that the temperature was 110 ° C. and the drying time was 2 minutes.

(Combination process)
Four sheets of 0.3 to 0.4 mm thick phenol resin-impregnated core paper are laminated, and the melamine resin-impregnated paper sprayed with the alumina particles obtained by the above process is laminated on the outer surface of the melamine resin-impregnated paper. The release cushion material made of PET is interposed between the press surface of the press machine and the alumina particle sprayed surface of the melamine resin-impregnated paper, and the temperature is 143 ° C., the press pressure is 80 kg / cm ² , the press time (temperature rise) Thermocompression bonding was performed in 50 minutes (including time). Thereby, the alumina particles were exposed and fixed on the melamine resin impregnated layer.

(Photocatalyst loading process)
A slurry in which a photocatalyst of CuO—TiO _{2 having} an average particle diameter of 100 nm is dispersed in water (solid content concentration: 25% by weight) and silica sol (SiO ₂ concentration: 3% by weight) are in a weight of 4.5: 5.5. A methanol mixed solution (photocatalyst concentration: 0.05% by weight) containing a ratio (solid content weight) is prepared. Using a spray, the methanol mixed solution is applied to a substrate having a melamine resin impregnated layer on the surface of which alumina particles obtained in the above step are disposed, and the solid content weight of the methanol mixed solution on the melamine resin impregnated layer is 0 The coating plate according to Example 1 in which the photocatalyst was supported on the exposed surface of the alumina particles was completed by applying the coating solution to .44 g / m ² and drying at 25 ° C. for 12 hours.

(Example 2)
In the (photocatalyst carrying step), the same procedure as in Example 1 was applied to Example ² except that the coating amount was changed so that the solid content weight of the methanol mixed solution on the melamine resin impregnated layer was 0.07 g / m ^2. The production of such decorative panels was completed.

(Example 3)
(Primary melamine impregnation process)
A paper roll having a thickness of 0.2 to 0.3 mm was immersed in a solution containing a melamine resin. The roll paper was impregnated with melamine resin by passing the roll paper while being immersed in the solution so that the temperature of the solution was 20 ° C. and the immersion time was 2 minutes. The moving speed of the roll paper was 10 to 20 cm / second.
(Drying process)
The roll paper that passed through the melamine solution was dried by a dryer (ESPEC, OVEN PH-201) so that the temperature was 100 ° C. and the drying time was 30 seconds.

(Secondary melamine impregnation process)
The paper roll which passed through the drying process was immersed in a solution made of melamine resin. The paper roll was impregnated with the melamine resin by passing the roll paper while being immersed in the solution so that the temperature of the solution was 20 ° C. and the immersion time was 30 minutes. The moving speed of the roll paper was 10 to 20 cm / second.
(Drying / cutting process)
The roll paper that passed through the melamine solution was dried by a dryer (ESPEC, OVEN PH-201) so that the temperature was 100 ° C. and the drying time was 2 hours. After drying, it was cut into 910 mm × 1820 mm.

(Alumina particle support process)
The surface of a polypropylene film having a thickness of 60 μm was roughened by corona discharge. The arithmetic average roughness (Ra) based on JIS B 0601 was 0.32 μm.
Subsequently, a spray liquid composed of γ alumina particles having an average particle diameter of 2 μm and ethanol was prepared. The spray liquid was filled in a spray at room temperature, sprayed onto the roughened polypropylene film, and dried at 25 ° C. to obtain an alumina particle-supporting film.
(Drying process)
The alumina particle-carrying film was laminated on melamine resin-impregnated paper so that the alumina particle carrying surface was in contact.

(Combination process)
Four sheets of phenol resin-impregnated core paper having a thickness of 0.3 to 0.4 mm are laminated, and a laminate of the alumina particle-supported film and melamine resin-impregnated paper obtained by the above process is laminated on the outermost polypropylene film. The release cushion material made of PET is interposed between the press surface of the press and the polypropylene film, and the temperature is 143 ° C., the press pressure is 80 kg / cm ² , the press time (including the temperature rise time) ) Thermocompression bonding was performed in 50 minutes. Further, the polypropylene film was removed, and the alumina particles were exposed and fixed on the melamine resin impregnated layer.

(Photocatalyst loading process)
A slurry in which a photocatalyst of CuO—TiO _{2 having} an average particle diameter of 100 nm is dispersed in water (solid content concentration: 25 wt%) and silica sol (SiO ₂ concentration: 3 wt%) are 5.4: 4.6 in weight. A methanol mixed solution (photocatalyst concentration: 0.06% by weight) containing a proportion (solid content weight) was prepared. The methanol mixed solution was applied using a spray to a substrate having a melamine resin-impregnated layer with alumina particles disposed on the surface, obtained in the above step, and dried at 25 ° C. for 12 hours. Next, the surface of the decorative board was wiped off with a microfiber cloth soaked with ethanol to remove the photocatalyst remaining on the surface other than the alumina particle surface, and the solid content weight of the methanol mixed solution on the melamine resin impregnated layer was 0.50 g / m ^2. Production of the decorative board according to Example 3 in which the photocatalyst was supported on the exposed surface of the alumina particles was completed.

Example 4
In the (photocatalyst carrying step), the same procedure as in Example 2 was followed to Example 4 except that the coating amount was changed so that the solid content weight of the methanol mixed solution on the melamine resin impregnated layer was 0.065 g / m ^2. The production of such decorative panels was completed.

(Comparative Example 1)
In the (photocatalyst carrying step), the coating amount was changed so that the solid content weight of the methanol mixed solution on the melamine resin impregnated layer was 0.06 g / m ^2. The production of such decorative panels was completed.

(Comparative Example 2)
In the (photocatalyst carrying step), the coating amount was changed so that the solid content weight of the methanol mixed solution on the melamine resin impregnated layer was 0.05 g / m ^2. The production of such decorative panels was completed.

(Comparative Example 3)
In the (photocatalyst supporting step), the same procedure as in Example 1 was applied to Comparative Example 3 except that the coating amount was changed so that the solid content weight of the methanol mixed solution on the melamine resin impregnated layer was 0.80 g / m ^2. The production of such decorative panels was completed.

(Measurement of Ti / Al molar ratio in surface resin layer)
Using a scanning electron microscope and an energy dispersive X-ray analyzer (SEM / EDX), elemental analysis was performed on the surfaces of randomly selected alumina particles on the surfaces of the decorative plates according to the examples and comparative examples. (Acceleration voltage: 10 kV). From the result of the obtained elemental analysis, the existence ratio (Ti / Al molar ratio) of Ti atoms and Al atoms in the region was measured. The above procedure was performed in four regions, and the average value was calculated. The results are shown in Table 1.
The SEM / EDX analysis area is an area of φ0.3 μm.

(An endurance test)
In order to evaluate the antiviral properties and the deterioration of the appearance after the durability test of the decorative plates according to each Example and Comparative Example, first, a durability test was performed. In the durability test, a weather resistance tester specified in JIS B 7751 (2007) was used, and the WV-A method specified in JIS A 1415 (2013) was performed for 48 hours.
In addition, about the decorative board which concerns on the comparative example 2, since a virus inactivity was low originally, the endurance test was not done.

(Antiviral evaluation)
Next, the virus inactivity was measured for the decorative board after the durability test according to the antiviral test method of the JIS R1756 visible light responsive photocatalytic material. The measurement result is expressed as the concentration of virus inactivated against E. coli.
Here, the concentration of virus inactivated against E. coli (virus inactivity) is used as an indicator of virus concentration. Virus inactivity is an antiviral test using bacteriophage, and the concentration of virus capable of infecting E. coli is measured by using phage virus Qβ concentration: 8.3 million / ml. On the other hand, the concentration of the inactivated virus is calculated. That is, the virus inactivity is a degree of concentration at which E. coli cannot be infected with respect to the phage virus Qβ concentration, and (phage virus Qβ concentration−virus concentration capable of infecting E. coli) / (phage virus Qβ concentration) × 100. It can be said that the higher the virus inactivation value, the better the antiviral properties.
The concentration of virus capable of infecting E. coli is measured as follows. A test solution having a known phage virus concentration (8.3 million pieces / milliliter) is dropped on a decorative plate and irradiated with light according to JIS R1756 to inactivate the virus, and then the decorative plate is washed with a predetermined amount of water. This is diluted 1000 times, transplanted and cultured in an E. coli medium, and the number of inactivated viruses is counted. The concentration of virus capable of infecting E. coli is calculated from the number of inactivated viruses, the amount of water used for washing, and the dilution rate.
Further, the virus inactivity is calculated from the virus inactivity.
The virus inactivity is a numerical value represented by the common logarithm log (1-X), where the amount of the original virus is 1 and the relative amount of virus inactivated after the virus inactivation treatment is X (negative negative). The greater the absolute value, the higher the ability to inactivate the virus. For example, when 99.9% of the original virus is inactivated, the virus inactivity is expressed as log (1−0.999) = − 3.00. The ratio of the amount of virus inactivated after virus inactivation treatment to the total amount of virus before virus inactivation treatment in% (in this case, 99.9%) is referred to as virus inactivity.
The measurement results are shown in Table 1.
In the present invention, an endurance test is performed assuming that ultraviolet rays contained in sunlight are irradiated for a long time after the decorative plate is applied, and the ratio of titanium oxide to aluminum oxide (Ti / Al) supported on the surface resin layer is In the case of 0.5-1.5, it turns out that an antiviral function does not fall by an endurance test. The reason for this is presumed that the aluminum oxide-containing particles can absorb ultraviolet rays to prevent the resin from deteriorating, and the photocatalyst and the aluminum oxide-containing particles can be prevented from falling off from the resin surface. When the photocatalyst is a visible light responsive photocatalyst, if the Ti / Al molar ratio is too large, the photocatalyst covers the surface of the aluminum oxide-containing particles, and the aluminum oxide cannot sufficiently absorb ultraviolet rays, causing deterioration of the resin. However, it is assumed that the photocatalyst and aluminum oxide from the resin surface fall off and the antiviral function is lowered.

実施例１〜４、比較例２については外観の変色はみられなかったが、比較例１、３は外観の変色が確認される。

In Examples 1 to 4 and Comparative Example 2, no discoloration of the appearance was observed, but in Comparative Examples 1 and 3, discoloration of the appearance was confirmed.

From the results in Table 1, it can be seen that the decorative board of the present invention has sufficient weather resistance and antiviral properties, and can exhibit an excellent antiviral effect over a long period of time.

DESCRIPTION OF SYMBOLS 1, 3 Decorative board 12 Surface resin layer 13 Aluminum oxide containing particle 14 Titania containing photocatalyst 15 Surface resin layer surface 16 Surface resin layer surface containing silicone resin and / or silane coupling agent 17 Functional substance A Whole surface resin layer Surface area B Total surface area of the surface resin layer in which the aluminum oxide-containing particles are exposed.

Claims (9)

A substrate,
A surface resin layer laminated on one or both surfaces of the substrate;
Aluminum oxide-containing particles that are exposed and arranged on the surface resin layer,
A titania-containing photocatalyst supported on the exposed surface of the aluminum oxide-containing particles,
The decorative board characterized in that the molar ratio of Ti / Al on the surface of the surface resin layer is 0.5 to 1.5. The decorative sheet according to claim 1, wherein the aluminum oxide-containing particles are particles made of either alumina or strontium aluminate. The decorative board according to claim 1 or 2, wherein the average particle diameter of the aluminum oxide-containing particles is 0.1 µm to 55 µm. The decorative sheet according to any one of claims 1 to 3, wherein the aluminum oxide-containing particles are exposed with an area ratio of 5 to 30% with respect to the surface resin layer surface. The decorative plate according to any one of claims 1 to 4, wherein the titania-containing photocatalyst is a visible light responsive photocatalyst. 6. The decorative board according to claim 5, wherein the visible light responsive photocatalyst is a platinum-supported titania catalyst, a copper-supported titania catalyst, an iron-supported titania catalyst, a nitrogen-doped titania catalyst, a sulfur-doped titania catalyst, or a carbon-doped titania catalyst. The said surface layer resin layer is a decorative board in any one of Claims 1-6 containing a silicone resin and / or a silane coupling agent. The decorative board according to any one of claims 1 to 7, wherein a dry layer of silica sol is provided on a surface layer of the aluminum oxide-containing particles. The aluminum oxide-containing particles are buried and fixed so as to be exposed from the surface resin layer, and the titania-containing photocatalyst is supported on an exposed surface of the aluminum oxide-containing particles so as not to directly contact the surface resin layer. Item 10. The decorative board according to any one of Items 1 to 8.

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