Coated sheet having antibacterial performance

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention relates to a coated plate in which antibacterial performance is imparted to all base materials such as plastic, paper, wood, metal plate, and inorganic material.

【0002】

[Conventional technology]

Conventionally, in order to impart antifungal or antibacterial properties to decorative paper, decorative boards, etc., a method of adding or kneading an antifungal agent or antibacterial agent into the corresponding material, or a method of painting in a post-process, etc. It was carried out (Gazette No. 63-54013, Gazette No. 4-28646). In addition, wallpaper and decorative sheets having antifungal and antibacterial properties are also known and commercially available (Japanese Unexamined Patent Publication No. 1-313333). However, antibacterial properties are required only on the extremely thin surface of the decorative material, but conventionally, a method of kneading into a resin or a method of kneading into a paint has been adopted, and an optimum antibacterial coating film forming method is not always required. I couldn't say that.

【0003】

[Problems to be Solved by the Invention]

Conventionally, mold and various equipment (electrical products, various appliances, etc.) have been used for indoor water supply (kitchen, bathroom, laundry, etc.), hot and humid places, hospitals and other places that require a hygienic environment. There is a demand for products that can prevent the outbreak of bacteria and the like. However, when a fungicide or an antibacterial agent is kneaded into a plastic molded product or the like, problems such as an increase in the manufacturing process and cost and a decrease in productivity are likely to occur. Further, when an antibacterial agent is kneaded into a molding resin or a paint resin, pigments, dyes, curing agents, catalysts, etc. are mixed in the resin as necessary components for the resin composition, and these substances are mixed. The antibacterial agent may be adversely affected by discoloration, deterioration of antibacterial action, etc., and it is necessary to individually examine the suitability with each resin.

【0004】

Therefore, the conventional resin composition cannot be used as it is, and it is necessary to examine the resin composition for each base material and application, which causes a problem that the work becomes complicated. In addition, when an antibacterial agent is kneaded into a molding resin, most of the antibacterial agents are kneaded into the resin and are contained in the molded product and do not show an antibacterial effect, so that the antibacterial agent can be used economically. It becomes a big problem.

【0005】

In order to solve these problems, the present invention uses an antibacterial agent containing metal ions such as antibacterial zeolite and a metal compound in a resin to which substances that adversely affect the antibacterial agent such as pigments, dyes, curing agents and catalysts are not added. A resin composition is prepared by mixing, and this is applied very thinly on the outermost surface of the decoratively processed base material, while substances that adversely affect antibacterial agents such as pigments and catalysts are used as resins that form another layer. By mixing, the purpose is to impart antibacterial performance to the product while maintaining the original performance of the paint.

【0006】

[Means for solving problems]

A resin in which an antibacterial agent is added to a transparent thermosetting resin excluding an acid catalyst after forming a resin layer to which a coloring pigment is added in a coated plate in which a resin layer to which a coloring pigment or the like is added is formed on the surface of a base material. The composition was a coated plate having antibacterial performance, characterized in that a thin antibacterial resin layer was formed on the uppermost layer of the base material. Further, in a coated plate in which a resin layer to which a coloring pigment or the like is added is formed on the surface of a base material, after forming a thermosetting resin layer to which an acid catalyst is added, antibacterial action is applied to a transparent thermosetting resin excluding the acid catalyst. A coated plate having antibacterial performance, characterized in that a thin antibacterial resin layer was formed on the uppermost layer of the base material in the resin composition to which the agent was added.

【0007】

Further, the antibacterial agent is an antibacterial zeolite in which some or all of the ion-exchangeable ions of the zeolite are replaced with ions such as silver, copper, zinc, tin, lead, mercury and ammonium. A coated plate using a resin layer was used. The antibacterial performance is characterized in that the coating base material is a metal plate, the content of the antibacterial zeolite in the resin composition is 1 to 10% by weight, and the thickness of the antibacterial resin layer is 2 to 10 μm. It was made into a painted plate having.

【0008】

[Action]

By forming the thin antibacterial resin layer of the present invention on the surface of various base materials, it can be used for various equipment in indoor water-related areas, hot and humid places, hospitals and other places requiring a hygienic environment. It is possible to prevent the growth of mold and bacteria. In addition to the thin layer on the outermost surface, components such as a curing catalyst and a coloring pigment that are originally required for the resin layer are added, so that the color tone, layer strength, and adhesion to the base material of the entire resin layer are improved. It is expressed. Moreover, since the antibacterial agent and the component that inhibits the antibacterial agent do not come into contact with each other, the antibacterial agent does not deteriorate.

【0009】

[Example]

Hereinafter, examples of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of a coated plate having antibacterial performance according to the present invention. FIG. 2 is a cross-sectional view showing another example of a coated plate having antibacterial performance. FIG. 3 is a cross-sectional view showing an example of a conventional coated plate having no antibacterial performance. FIGS. 4 and 5 are cross-sectional views of a coated plate showing a comparative example in which antibacterial performance cannot be sufficiently exhibited even when a paint to which antibacterial zeolite is added is used.

【0010】

As shown in FIG. 1, the primer 14 is applied to the base sheet 15 and dried, and then a paint to which a pigment, a filler, etc. is added is applied to form a base coat layer 13, and then a dry substance is added to a transparent resin solution. A resin composition containing 1 to 10% of antibacterial zeolite 12 added to the weight is applied to form an antibacterial resin layer 11 having a thickness of 2 to 10 μm to prepare a coated plate 1 having antibacterial performance.

【0011】

As the base material used for the coated plate having the antibacterial performance of the present invention, metal plates such as iron, aluminum, stainless steel and copper, wood veneer, wood plywood, wood plywood such as particle board, gypsum board, concrete board and A ceramic inorganic plate such as a calcium acid plate, or an appropriate composite of the above materials of each base material can be used. In addition, polyester sheets such as paper, polyvinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyethylene terephthalate-isophthalate copolymer, polytetrafluorovinyl, polyvinylidene fluoride, polytetrafluoride ethylene, and ethylene-4fluoroethylene Polyethylene resin film such as a polymer, plastic sheet such as polyimide or polycarbonate sheet, metal foil such as aluminum, copper, tin, iron or lead, or an appropriate composite of the above materials of each base material is used. Can be done.

【0012】

The coated plate is usually provided with a base coat layer and a pattern layer, but the resin used for the base coat layer includes a thermoplastic resin such as polyvinyl chloride and acrylic, a thermosetting resin such as saturated polyester, polyurethane, epoxy and melamine, and acrylic. Resins conventionally used for making decorative materials such as ionizing and thermosetting resins such as based and unsaturated polyester based resins can be used. Further, a thermosetting resin using an acid catalyst can also be used in order to improve physical properties such as heat resistance of the base coat layer, coating film strength, and bending processability.

【0013】

The above resins include pigments, dyes, fillers, catalysts, cross-linking agents, stabilizers, dispersants, and anti-settling agents necessary to give the coated plate the desired physical properties such as color tone, layer strength, and adhesive strength to the substrate. Microsilica, solvent and diluent are appropriately added, kneaded and used as a coating liquid.

【0014】

However, when these substances are added together with an antibacterial agent, they may inhibit the antibacterial property or cause a reaction between the antibacterial agent and a reducing component to cause discoloration, and as a layer separate from the antibacterial agent. Need to form. Therefore, in order to impart a color design and physical properties to the base material, substances that must be added to the coating film must be added to the base coat layer. Of course, if an additive that interacts with a colorant or an antibacterial agent and has an adverse effect is not required, the antibacterial resin layer may be formed directly on the base material.

【0015】

The resin used for the antibacterial resin layer must not contain a substance that adversely affects the antibacterial agent, and may be colored by reacting with the antibacterial agent or discolored by heat, light, ionizing radiation, or the like. You can't use something like that. In particular, do not add acid catalysts used for curing thermosetting resins, compounds having the property of reducing metal ions of antibacterial agents, and the like. To give a specific example, when a zeolite having silver ions, which will be described later, is used as the antibacterial agent, an acid catalyst such as an organic sulfonic acid catalyst used as a curing catalyst for saturated polyester, iron having a higher ionization tendency than silver, Do not add coloring pigments or heat stabilizers made of metal compounds such as cobalt, copper, and lead. Preferred antibacterial resin layers include thermosetting resins containing polyester, polyurethane, epoxy, and alkyd as main components, which are combined with melamine, guanamine, and urea resin.

【0016】

Examples of the thermoplastic resin that can be used include vinyl resin-based resins such as polyvinyl chloride, (meth) acrylic acids such as methyl poly (meth) acrylic acid, ethyl poly (meth) acrylic acid, and butyl poly (meth) acrylic acid. There are acrylic resin type, alkyl resin type and the like such as ester alone or copolymer (however, (meth) acrylic means acrylic or methacrylic). In addition, methyl poly (meth) acrylate means methyl polyacrylate or methyl polymethacrylate, and the following (meth) is used in the same meaning.

【0017】

Examples of the thermosetting resin include polyester resin-based, epoxy resin-based, polyurethane resin-based, aminoalkyd resin-based, melamine resin, guanamine resin, urea resin, and thermosetting acrylic resin.

【0018】

The ionizing radiation curable resin has a composition composed of a monomer and / or a prepolymer containing a polymerizable unsaturated group such as a (meth) acryloyl group and a (meth) acryloyloxy group, an epoxy group, a thiol group, etc. in the molecule. It is a product obtained by polymerizing (crosslinking reaction, additive reaction, etc.) with ionizing radiation, and electron beam, ultraviolet rays, etc. are used as the ionizing radiation. Examples of these prepolymers include (meth) acrylates such as urethane (meth) acrylates, polyester (meth) acrylates, and epoxy (meth) acrylates, unsaturated polyesters, and the like. Examples of monomers include styrene-based monomers such as styrene and α-methylstyrene, methyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and dipentaerythritol penta. There are (meth) acrylate, trimethylolpropane tri (meth) acrylate and the like.

【0019】

As the antibacterial agent added to the resin composition forming the antibacterial resin layer, a generally commercially available industrial antibacterial agent can be used. Industrial antibacterial agents include organic antibacterial agents and inorganic antibacterial agents. Inorganic antibacterial agents are suitable for the present invention in terms of thermal stability. In particular, as an inorganic antibacterial agent, some or all of the ion-exchangeable ions of zeolite disclosed in Japanese Patent Publication No. 63-54013, Japanese Patent Publication No. 4-28646, etc. are silver, copper, zinc, tin, etc. Antibacterial zeolites substituted with ions such as lead, mercury, cobalt and ammonium are suitable.

【0020】

In addition, anhydrous aluminosilicate, apatite, which has a non-zeolite structure and supports a metal such as silver, copper, zinc, nickel, manganese, cobalt, or metal ions, as disclosed in Japanese Patent Application Laid-Open No. 4-300975. One or more sintered powders selected from borosilicate silicate can also be used as antibacterial agents.

【0021】

Further, a compound represented by the following general formula [1] as disclosed in Japanese Patent Application Laid-Open No. 5-59308 can also be used as an antibacterial agent. M¹_aA_bM²_c(PO₄)_d NH₂O [1] M¹Is at least one metal ion selected from silver, copper, zinc, tin, mercury, lead, cobalt, nickel, manganese, arsenic, antimony, bismuth, barium, cadmium or chromium, and A is alkali metal ion, alkaline soil. At least one ion selected from metalloid ions, ammonium ions or hydrogen ions, M²Is a tetravalent metal, n is a number satisfying 0n6, a and b are both positive numbers, and c and d are c = 2 and d = 3 when la + mb = 1. , La + mb = 2, c = 1, d = 2. However, l is M¹Is the valence of, and m is the valence of A.

【0022】

As the particle size of the inorganic antibacterial agent, an appropriate particle size distribution in the range of 0.1 to 10 μm is used for an addition amount of 1 to 10% by weight and a coating thickness (dry matter) of 2 to 10 μm. It is preferable to give the maximum antibacterial action with the minimum addition amount. Especially, the particle size of 2 to 5 μm is good. In the resin composition to which the antibacterial agent is added, it is necessary to remove the components that adversely affect the antibacterial agent, and a simple system of the resin component, the solvent and the antibacterial agent is desirable. Since most of the resin compositions are desired to be transparent when a coating film is formed, the amount of the inorganic antibacterial agent added, which is insoluble in a solvent, is limited. Further, metals such as silver and nickel often cause discoloration, deterioration and deterioration of organic compounds, and from this point as well, excessive addition is not preferable.

【0023】

In the case of the above antibacterial agent, the content of the antibacterial zeolite is preferably in the range of 1 to 10% by weight as the amount of dry matter when the resin composition forms a coating film, and 2 when the antibacterial effect and transparency are emphasized. ~ 5% by weight is suitable. If the content of the antibacterial zeolite exceeds 10% by weight, the above-mentioned problem cannot be ignored, and if it is less than 1% by weight, a sufficient antibacterial action cannot be obtained.

【0024】

As a method of forming an antibacterial resin layer on a base-coated base material using a resin composition to which an antibacterial agent is added, gravure coat, roll coat, air knife coat, kiss coat, spray coat, wheeler coat, curtain flow coat, brush It can be performed by painting or gravure printing, gravure offset printing, intaglio printing, silk screen printing, or the like.

【0025】

Since the antibacterial resin layer exerts the maximum antibacterial effect with the minimum addition amount, it is necessary that some of the antibacterial agent particles are exposed on the surface of the coating film, and the amount of the antibacterial agent added is 1 to 10% by weight. The thickness of the coating film should be about 2 to 10 μm, and the antibacterial agent particles should be preferably about 2 to 5 μm. If the coating amount is insufficient due to the coating method, overprinting may be performed from one coat to two to three coats. However, when the particle size of the antibacterial agent is large or the amount added is large, the antibacterial effect can be exhibited even if the thickness of the coating film exceeds 10 μm, but transparency is not desired. In addition, the proportion of substances that are sealed inside the coating film and do not directly contribute to the antibacterial action increases. If the coating film is made less than 2 μm, the sufficient durability of the coating film and the binding force for adhering the inorganic antibacterial agent having the particle size and the added amount to the coating film become insufficient.

【0026】

Next, as a specific example, the first embodiment is shown below. As shown in FIG. 1, a zinc-plated iron plate (manufactured by Shin Nihon Steel Co., Ltd.) with a thickness of 0.6 mm is used as the base material 15, and after pretreatment, a commercially available polyester-based primer solution is rolled-coated. A thermosetting polyester resin paint (The Inktech) with the following composition, which is coated and dried with a primer coat layer 14 and containing a titanium dioxide coloring pigment and an organic sulfonic acid-based curing acid catalyst. A base coat layer 13 having a thickness of 20 μm was formed by a curtain flow coating method using (manufactured by Co., Ltd.). Composition of thermosetting polyester resin paint Saturated polyester resin 20 parts by weight 5 parts by weight of melamine resin 0.3 parts by weight of organic sulfonic acid catalyst Titanium oxide 25 parts by weight ·solvent Appropriate amount Appropriate amount of additives Further, as the pattern layer 16, a wood grain pattern was gravure offset printed by two-color printing using a polyesul resin-based ink (manufactured by The Inktech Co., Ltd.).

【0027】

Next, the antibacterial resin layer 11 is formed by diluting it to an appropriate viscosity with an organic solvent using the following antibacterial agent-added resin solution and coating it to a thickness of 3 μm in a dry state by a gravure offset coating method. , 220 ° C, 120 seconds baking to produce a decorative steel sheet 1 with antibacterial performance. As an antibacterial agent, it is an antibacterial zeolite manufactured by Shinagawa Fuel Co., Ltd., and its properties are that the average particle size is 5 μm or less, the silver (Ag) content is 2.5 ± 0.5% by weight, and the zinc (Zn) content is 14.5 ± 1.5. The one by weight% was used. In addition, microsilica has an average primary particle size of 16 nm and a specific surface area of 110 m.²I used the one of / g. Composition of antibacterial agent-added resin liquid Antibacterial zeolite (particle size distribution 2-5 μm) 3 parts by weight Saturated polyester resin (without acid catalyst) 77 parts by weight 20 parts by weight of melamine resin Microsilica 0.4 parts by weight [0028]

(Comparative Example 1) In the same manner as in the first embodiment, after forming the primer coat layer, the base coat layer, and the pattern layer, a curable polyester resin (without an acid catalyst) to which antibacterial zeolite is not added is coated, and the figure is shown. A decorative steel sheet 2 having a structure as shown in 3 was manufactured and used as Comparative Example 1.

【0029】

In the second embodiment, the barrier layer 17 is provided between the base coat layer 13 and the antibacterial resin layer 11, and the configuration is as shown in FIG. After primer coating a 0.6 mm thick zinc-plated iron plate pretreated as a base material, a base coat layer 13 having a thickness of 20 μm was applied by a curtain flow coating method using the same thermosetting polyester resin as in the first embodiment. Next, a barrier layer 17 having a thickness of 2 to 4 μm was formed by a gravure offset coating method using a polyester resin-based clear ink containing no pigment, acid catalyst, or antibacterial agent. Further, using the following antibacterial agent-added resin solution, the antibacterial resin layer 11 having a thickness of 3 μm is formed in a dry state by a gravure offset coating method after diluting with an organic solvent to an appropriate viscosity. By baking in the same manner as in the above, a decorative steel sheet 1 having antibacterial performance was produced. Composition of antibacterial agent-added resin liquid Antibacterial zeolite (particle size distribution 2-5 μm) 5 parts by weight Saturated polyester resin (without acid catalyst) 75 parts by weight 20 parts by weight of melamine resin Microsilica 0.4 parts by weight [0030]

The third embodiment is a case where an aluminum plate is used as a base material, and has a configuration as shown in FIG. After forming the primer coat layer 14, the base coat layer 13 with a thickness of 20 μm, and the pattern layer 16 on the base material 15 of the aluminum plate (thickness 2 mm) in the same manner as in the first embodiment, the following antibacterial agent-added resin solution is formed. To form an antibacterial resin layer 11 having a thickness of 5 μm in a dry state by a gravure offset coating method after diluting with an organic solvent to an appropriate viscosity, an aluminum veneer 1 having antibacterial performance was prepared. Composition of antibacterial agent-added resin liquid Antibacterial zeolite (particle size distribution 2-5 μm) 4 parts by weight Saturated polyester resin (without acid catalyst) 76 parts by weight 20 parts by weight of melamine resin Microsilica 0.4 parts by weight [0031]

(Comparative Example 2) In the same manner as in the third embodiment, after forming the primer coat layer, the base coat layer, and the pattern layer, a curable polyester resin (without an acid catalyst) to which antibacterial zeolite is not added is coated to make aluminum. A plate was prepared and used as Comparative Example 2.

【0032】

The fourth embodiment is a case where a stainless steel plate is used as a base material, and has a configuration as shown in FIG. After forming the primer coat layer 14, the base coat layer 13 with a thickness of 20 μm, and the pattern layer 16 on the base material 15 of the stainless steel plate (thickness 0.6 mm) in the same manner as in the first embodiment, the following antibacterial agent-added resin Using the liquid, it was diluted to an appropriate viscosity with an organic solvent, and an antibacterial resin layer 11 having a thickness of 5 μm was formed in a dry state by a gravure offset coating method to prepare a stainless steel decorative plate 1 having antibacterial performance. Composition of antibacterial agent-added resin liquid Antibacterial zeolite (particle size distribution 2-5 μm) 3 parts by weight Saturated polyester resin (without acid catalyst) 76 parts by weight 20 parts by weight of melamine resin Microsilica 0.4 parts by weight [0033]

(Comparative Example 3) In the same manner as in the fourth embodiment, after forming the primer coat layer, the base coat layer, and the pattern layer, a curable polyester resin (without an acid catalyst) to which antibacterial zeolite is not added is coated to make stainless steel. A plate was prepared and used as Comparative Example 3.

【0034】

(Comparative Example 4) After forming the primer coat layer 14 and the base coat layer 13 using the same base material treated in the same manner as in the first example, the same thermosetting property as in the first example. An antibacterial resin layer 11 is formed from a resin composition obtained by adding 0.5 parts by weight of antibacterial zeolite 12 and a titanium dioxide pigment to a polyester resin liquid to prepare a decorative steel plate having a constitution as shown in FIG. 4, and Comparative Example 4 And said.

【0035】

(Comparative Example 5) A primer coat layer 14 is formed using the same base material treated in the same manner as in the first example, and then antibacterial with a base coat resin solution containing 5% of antibacterial zeolite. A zeolite-added base coat layer 19 was formed to prepare a decorative steel sheet having a structure as shown in FIG. 5, which was used as Comparative Example 5.

【0036】

(Antibacterial property test) The inhibitory effect on bacteria was tested on the decorative steel plate, aluminum decorative plate, stainless steel decorative plate and Comparative Example produced in the above Examples by the following methods. Test strain Escherichia coli IFO 3301 (Escherichia coli, hereinafter referred to as E. coli) Methicillin Resistant Staphylococcus aureus (Methicillin Resistant Staphylococcus aureus, hereinafter referred to as MRSA) Preparation of test bacterial solution The culture solution of the test bacteria cultured in ordinary bouillon medium (manufactured by Eiken Kagaku Co., Ltd.) at 35 ° C. for 16 to 20 hours was diluted 20,000 times with sterile phosphate buffer to obtain a bacterial solution. In addition, the viable cell count was separately measured for the bacterial solution. Antibacterial test 1 ml of the bacterial solution was added dropwise to the antibacterial resin layer surface of the sample (decorative steel plate and decorative material), and after storage at 25 ° C for 24 hours, the number of bacteria was measured to determine the antibacterial performance of the sample. As a control sample, 1 ml of the bacterial solution was added dropwise to the petri dish and tested in the same manner. Measurement of viable cell count SCDLP (Soy Casein Digest) of samples and control samples stored for 24 hours Lecithin Polysorbate) Medium (manufactured by Nihon Pharmaceutical Co., Ltd.) Washed out with 10 ml, and this washed-out solution was cultivated by a pour plate culture method (35 ° C, 2-day culture) using a standard agar medium (manufactured by Eiken Kagaku Co., Ltd.). The viable cell count was measured, and the bacterial count per sample and control sample was calculated.

【0037】

The test results are shown in Table 1. All of the samples prepared in the examples had an excellent bactericidal effect, and the antibacterial performance of the cosmetic material having the antibacterial performance of the present invention could be demonstrated. That is, with the decorative board prepared in Examples 1, 2, 3 and 4, after 24 hours, the initial number of bacteria in E. coli was 1.2 × 10.⁵From 1 to 30, with MRSA, the initial number of bacteria is 2.4 x 10⁵The number has decreased from 10 to 10 or less, and the sterilization rate of the decorative board against E. coli and MRSA is 99.99% or more. On the other hand, in Comparative Example 4 in which 0.5% of antibacterial zeolite was added, the bactericidal rate against E. coli and MRSA was about 90%, and the bactericidal effect was insufficient. (Usually, when sterilizing microorganisms, it is hard to say that the sterilization effect is sufficient with a sterilization rate of 2 or 3 digits from the initial number of bacteria, that is, a sterilization rate of 99% or 99.9%). [0038]

Therefore, it is shown that 0.5% of the amount of antibacterial zeolite added to the paint is not sufficient when making a coated plate having an antibacterial action. In addition, although the decorative board produced in Comparative Example 5 contains 5% of the antibacterial zeolite added to the paint, the bactericidal rate against E. coli and MRSA is as low as about 90%, and the bactericidal effect is insufficient. Is. This is because the antibacterial zeolite was directly added to the base coat resin liquid containing the acid catalyst, and indicates that the antibacterial action was extremely reduced by the acid catalyst and the like contained in the base coat resin. Therefore, according to the present invention, by providing the resin layer to which the antibacterial zeolite is added separately from the base coat layer containing the acid catalyst, a new effect can be produced and the bactericidal effect of the antibacterial zeolite can be maximized. ..

【0039】

[table 1]

<img file="JPH081079A_D0001.tif" />【0040】

(Chemical resistance test) The chemical resistance test was performed on the decorative steel plate, aluminum decorative plate and stainless steel decorative plate produced in the above Examples and Comparative Examples by the following method. As test reagents, acetic acid, hydrochloric acid, sulfuric acid, caustic soda, 5% aqueous solution of ammonia and Magiclin stock solution were used. The test method is to immerse the test piece sealed except for the painted surface in the aqueous solution and stock solution of the above reagent at a liquid temperature of 20 ° C for 24 hours, then wash the test piece with water and compare the color, appearance, etc. with the control untested sample. did. The evaluation method is indicated by × as shown below. : No discoloration : Slight discoloration ×: Significant discoloration The test results are shown in Table 2, and all the decorative boards produced in Examples were superior in chemical resistance to Comparative Example 5.

【0041】

[Table 2]

<img file="JPH081079A_D0002.tif" />【0042】

(Weather resistance test) In order to investigate the effect of acid catalyst addition on the antibacterial resin layer, the same as in Example 1 (excluding the pattern layer), the antibacterial resin layer 11 does not contain an acid catalyst. A resin containing 5% of antibacterial zeolite was prepared and used as a sample for weather resistance test. In addition, as a comparative example, a sample was prepared by adding 5% of antibacterial zeolite to a resin containing an acid catalyst, and used as a comparative sample.

【0043】

The following tests were performed on the sample. Weather resistance test Each of the above samples was irradiated with a sunshine-carbon arc lamp weatherometer (black panel temperature 63 ° C) for 250 hours, and changes in surface gloss and color difference before and after irradiation were measured. How to measure surface gloss The 60-degree specular reflectance was calculated using a digital variable angle gloss meter VG-1D manufactured by Nippon Denshoku Kogyo Co., Ltd. in accordance with JIS / Z / 8741 (gloss measurement method). Color difference measurement method According to JIS / Z / 8730 (color difference display method), L, a, b before and after sunshine irradiation are measured using Suga Test Instruments SM color computer SM-6-IS-2BG type, and ΔL, Δa and Δb were calculated, and the color difference ΔE of the Lab system was calculated. However, ΔE is (ΔL)²+ Δa²+ Δb²) Is the square root.

【0044】

The test results are shown in Table 3, and the decorative steel sheet produced in the examples was superior in weather resistance to the comparative examples. That is, it became clear that adding antibacterial zeolite to a paint containing an acid catalyst has problems not only in terms of antibacterial performance but also in terms of weather resistance, demonstrating the effectiveness of the present invention.

【0045】

[Table 3]

<img file="JPH081079A_D0003.tif" />【0046】

[Effect of the present invention]

By using the coating plate having the antibacterial performance of the present invention, it is possible to impart antibacterial performance to various equipment related to indoor water, hot and humid places, hospitals and other places requiring a hygienic environment. .. In particular, when the antibacterial resin layer of the present invention is formed on a decorative steel sheet and used for partitioning a hospital, a tsuitate, etc., it exhibits a bactericidal action against adhered bacteria, so that the room can be kept clean and the hospital can be kept clean. It can also be expected to prevent contamination by infectious bacteria. Further, since the antibacterial agent is added to a very thin layer on the surface of the coated plate having the antibacterial performance of the present invention, the antibacterial effect can be imparted in a small amount, which is economically advantageous.

[Simple explanation of drawings]

[Figure 1]

FIG. 5 is a cross-sectional view showing an example of a coated plate having antibacterial performance according to the present invention.

[Figure 2]

FIG. 3 is a cross-sectional view of a decorative steel sheet having antibacterial performance according to the second embodiment.

[Fig. 3]

Cross-sectional view of a decorative steel sheet without antibacterial performance according to Comparative Example 1.

[Fig. 4]

FIG. 3 is a cross-sectional view of an antibacterial zeolite-added decorative steel sheet produced in Comparative Example 4.

[Fig. 5]

Cross-sectional view of the antibacterial zeolite-added decorative steel sheet produced in Comparative Example 5.

[Explanation of symbols]

1 Painted board with antibacterial performance 2 Decorative steel sheet without antibacterial performance 3 Decorative steel sheet with antibacterial agent added to the base coat layer 11 Antibacterial resin layer 12 Antibacterial zeolite 13 Base coat layer 14 Primer coat layer 15 Base material 16 pattern layer 17 Barrier layer 18 Clear clear layer without antibacterial agent 19 Base coat layer with antibacterial agent added