JP5745910B2 - Paint plate and manufacturing method thereof - Google Patents

Description

  The present invention relates to a coated plate used for interiors such as tunnels and a method for manufacturing the same.

  Paint plates used for interiors such as tunnels are required to have high durability and to maintain a predetermined reflectivity even after regular cleaning. A coated plate having a coating film formed by baking an inorganic coating material on a substrate made of an inorganic ceramic material such as a hard calcium silicate plate is used (Non-patent Document 1). However, since the use of asbestos has been banned, alternative materials are being sought. Various fibers have been proposed as asbestos substitute fibers, and organic fibers such as cellulose pulp are increasingly used.

Tunnel interior system, A & A Materials, 2002

  However, in the case of an inorganic ceramic board material with a relatively thin thickness such as an interior board reinforced with organic fibers, when an inorganic paint is baked onto the substrate to form a coating film, the organic fibers contained in the substrate There was a problem that the coating film could not be formed due to deterioration. On the other hand, when an ordinary organic paint is formed on a substrate, there is a problem that if the cleaning is repeated when the interior plate is contaminated, the reflectivity changes and it is not suitable as an interior plate such as a tunnel.

  Accordingly, an object of the present invention is to provide a coated plate that has high durability and maintains a predetermined reflectance even if it is periodically cleaned, even though no asbestos is used as a raw material for the substrate. It is in providing the manufacturing method.

Therefore, the present inventor has made various studies to improve the durability and reflectivity maintenance performance of the interior material using the fiber reinforced cement board as a substrate, and as a result, the substrate is overcoated with an impregnated sealer layer, a surfacer layer, and then an organopolysiloxane paint. By forming the layer, it was found that a coated plate having nonflammability and durability and having a reflectance that does not change even after washing was obtained, and the present invention was completed.

That is, the present invention provides a coated board comprising a fiber-reinforced cement board as a substrate, and an impregnated sealer layer, a surfacer layer, and an overcoat layer made of an organopolysiloxane paint are laminated in this order on one side of the substrate. To do.
Moreover, this invention provides the manufacturing method of the coating board characterized by including the process of the following (A) to (D).
(A) A step of preparing a fiber reinforced cement board as a substrate (B) A step of forming an impregnation sealer layer by applying an impregnation sealer to at least one surface of the substrate and impregnating the substrate, followed by drying by heating. (C) A step of applying a surfacer coating to one side of the substrate on which the impregnated sealer layer is formed and drying, and then polishing the surface to form a surfacer layer. (D) On the surfacer layer, an organo for topcoat layer The process of applying a polysiloxane paint and drying by heating to form a topcoat layer

  The coated plate of the present invention is suitable as an interior material for tunnels and the like because it has nonflammability and is less susceptible to surface diffuse reflectance reduction due to cleaning. Furthermore, if a non-combustible fiber cloth is bonded to the surface opposite to the coating film, it will not scatter even if it is damaged, and it will have durability without corrosion like a metal interior material. Sex can be maintained.

  The coated board of the present invention uses a fiber reinforced cement board as a substrate. The fiber reinforced cement board used as a substrate uses hydraulic cement such as Portland cement as the main raw material for forming the matrix, uses fibers other than asbestos as the fiber raw material, and if necessary, wollastonite and It is a board | substrate which uses admixtures, such as a calcium carbonate powder, as a raw material, and is specifically a board | substrate, such as a soft flexible board prescribed | regulated to JISA5430. In particular, as a raw material for forming a matrix, a kind of fiber reinforced cement board obtained by using a siliceous raw material such as powdered silica together with the hydraulic cement, pressurizing in a molding process, and performing autoclave curing in a curing process. The hard calcium silicate plate is a dense and flexible substrate, and has a high strength and a small rate of change in length due to water absorption. Therefore, it is suitable as a substrate for the coated plate of the present invention.

  The fiber reinforced cement board used as the substrate of the paint board of the present invention is preferably a thin board having a thickness of 3 to 8 mm from the viewpoint of workability when the paint board is constructed along the curved surface of the tunnel inner wall, A plate having a thickness of 3.5 to 4.5 mm is preferable. If the thickness of the substrate is less than 3 mm, the coated plate is likely to be damaged during transportation or construction, which is not preferable. If the thickness of the base material exceeds 8 mm, it is not preferable because it is difficult to construct the coated plate along a curved surface such as a tunnel inner wall.

As a method for forming such a thin fiber-reinforced cement plate, a papermaking method that is excellent in the orientation of the fiber raw material and can sufficiently exhibit the reinforcing performance of the fiber raw material is suitable. Water is added to and mixed with the raw material, and a green sheet is obtained by forming to a predetermined thickness using a papermaking method. The obtained green sheet is added at a pressure of 19.5 to 29.5 MPa. After pressing, an autoclave curing is performed at 160 to 190 ° C. for 4 to 15 hours to obtain a hard calcium silicate plate having an apparent density of 1.5 to 1.8 g / cm ³ suitable as a substrate of the present invention. Can do. When the apparent density of the substrate is less than 1.5 g / cm ³ , the material becomes porous and there is a risk that durability as an interior material such as a tunnel is lowered. Further, if the apparent density of the substrate exceeds 1.8 g / cm ³ , the material becomes hard, which is not preferable.

  When the papermaking method is used as the forming method, it is necessary to use organic fibers such as cellulose pulp from the viewpoint of formability, and the blending ratio is preferably in the range of 4 to 8% by mass of the entire raw material of the fiber reinforced cement board. Yes, and more preferably 6.5 to 7.5% by mass. If it is less than 4% by mass, the flexibility and strength of the resulting fiber-reinforced cement plate are lowered, which is not preferable. Also, if it exceeds 8% by mass, the calorific value of the base material will increase in the non-flammability test, so the coating layer of the paint plate must be thinned to ensure non-flammability, and the performance of the coating layer will deteriorate. This is not preferable.

An impregnation sealer layer is first laminated on one or both sides of the substrate. The impregnated sealer layer is formed for the purpose of reinforcing the surface of the substrate, sealing the alkali inside the substrate, and improving the adhesion of the surfacer layer as the next layer. As the sealer for forming the impregnation sealer layer, inorganic sealers such as silica, alumina and zirconia; rubber sealers such as styrene butadiene rubber, acrylic rubber, chlorinated rubber, chloroprene rubber, natural rubber, butyl rubber and nitrile butadiene rubber; hexa Organic sealers such as isocyanate sealers such as methylene diisocyanate (HMDI), methylene diisocyanate (MDI), and tolylene diisocyanate (TDI) are used. Of these, isocyanate-based sealers are particularly preferable. In the case of forming an impregnated sealer layer using an organic sealer, the organic solid content is preferably 1.3 to 7.5 g / m ² from the viewpoint of reinforcement, alkali sealing and surfacer layer adhesion, and more preferably 2.5. -7.5 g / m < ² > is more preferable. In addition, although an impregnation sealer layer may be only one side (front side surface), it is more preferable to form on both surfaces.

A surfacer layer is laminated on the surface of the impregnated sealer layer on the front side. The surfacer layer reduces the unevenness of the substrate, smoothes the base, improves the adhesion of the top coat layer, makes the base color up to the sealer layer uniform, and removes moisture, solvent components and resin from the base in the top coat process. Suppresses the emission and prevents the coating film from dropping or cracking due to flying objects or bending stress applied to the top coating surface after the coating plate is provided. It is formed for the purpose of preventing together with the sealer layer from reaching the topcoat layer. The paint for forming the surfacer layer is preferably a paint that is easy to fluff and polish. Acrylic urethane paint, vinyl resin paint, acrylic resin paint, synthetic resin emulsion paint, epoxy resin paint, silicone resin paint, acrylic Examples thereof include silicone resin-based paints, urethane resin-based paints, fluororesin-based paints, polyester resin-based paints, and alkyd resin-based paints. Of these, acrylic urethane paints are particularly preferred. Surfacer layer is preferably 5.0~15g / m ² as an organic solid content in terms of adhesion to the ease and overcoat layers of smoothing, further 6.7~13.4g / m ² is more preferable.

On the surface of the surfacer layer, an overcoat layer made of an organopolysiloxane paint is laminated. By adopting an organopolysiloxane-based paint as the top coat layer, in addition to water resistance, stain resistance, and durability, a decrease in reflectance due to washing is remarkably suppressed. As the organopolysiloxane paint, one-pack or two-pack organopolysiloxane paint is used. Specifically, a room temperature curable coating containing an organopolysiloxane compound having a plurality of alkoxy groups as a main component and containing a silane compound and / or acrylic resin having a crosslinkable group, and a curing catalyst can be mentioned. Here, examples of the crosslinkable group include an epoxy group, an acrylic group, and an amino group. Specific examples of these include organopolysiloxane paints described in JP-A No. 2000-631612, JP-A No. 2003-238895, JP-A No. 2006-36984, and JP-A No. 2006-36985. The overcoat layer, durability, preferably 10.2~50.9g / m ² as an organic solid content in terms of reflectance reduction preventing further 13.6~40.7g / m ² is more preferable.

In the coated plate of the present invention, if necessary, an impregnated sealer layer is formed on the surface opposite to the surface on the front side, and a non-combustible fiber cloth is adhered via an adhesive layer. It is preferable in terms of prevention of scattering, alkali water resistance, improvement of the appearance of the back surface, protection of the back surface of the coated plate, improvement of product bending strength, and simplification of the coating plate manufacturing process. As the adhesive used, epoxy adhesive, phenol resin adhesive, resorcinol adhesive, vinyl acetate adhesive, rubber adhesive, acrylic resin adhesive, cyanoacrylate adhesive, and the like are used. Non-combustible fiber cloth includes glass cloth, silicon carbide fiber cloth, alumina fiber cloth, silicon nitride fiber cloth, boron fiber cloth, boron / tungsten fiber cloth, alumina silica fiber cloth, zirconia fiber cloth, silica fiber cloth, stainless steel. Examples thereof include fiber cloth, and glass cloth is particularly preferable. The glass cloth may be a woven fabric made of glass fiber, but preferably has no mesh opening. The adhesive layer is preferably 23~90g / m ² as an organic solid content, particularly 36~90g / m ² is more preferable. The total amount of organic solids in the impregnated sealer layer, surfacer layer, topcoat layer, and adhesive layer of the tunnel coating plate is preferably 180 g / m ² or less from the viewpoint of nonflammability.

The coated sheet of the present invention is manufactured, for example, by a process including the following processes (A) to (D).
(A) A step of preparing a fiber reinforced cement board as a substrate (B) A step of forming an impregnation sealer layer by applying an impregnation sealer to at least one surface of the substrate and impregnating the substrate, followed by drying by heating. (C) A step of applying a surfacer coating to one side of the substrate on which the impregnated sealer layer is formed and drying, and then polishing the surface to form a surfacer layer. (D) On the surfacer layer, an organo for topcoat layer The process of applying a polysiloxane paint and drying by heating to form a topcoat layer

  In applying the impregnated sealer in the step (B), the substrate is preferably preheated to about 60 to 80 ° C. The impregnation sealer can be applied by, for example, a roll coater.

  In the surfacer layer forming step of the step (C), for example, it is dried after being applied with a roll coater and a flow coater. After drying, fluff removal polishing is performed to smooth the surfacer layer. Fluff removal polishing can be performed using a normal roll buffing machine. Thereafter, drying may be performed.

  The top coat layer forming step in the step (D) differs depending on the type of paint used, but after heating to about 60 to 80 ° C., the paint may be applied and dried.

The back side surface of the coated plate of the present invention is formed by impregnating a sealer layer if necessary, (E) applying an adhesive, placing a non-combustible fiber cloth thereon, pressurizing the non-combustible fiber cloth It is formed by adhering to a substrate. The pressurization of the non-combustible fiber cloth may be performed, for example, by placing a dummy plate and applying a load of 0.1 to 1 kg / cm ² from the top for 24 to 48 hours. In order to promote the curing of the adhesive in the bonding process of the non-combustible fiber cloth, the coated plate may be preheated (about 60 to 80 ° C) or heated (about 60 to 80 ° C) during pressurization. Good.

  The resulting coated plate of the present invention has an organopolysiloxane-based coating layer in the top coat layer, so it is excellent in durability and water resistance, and has a small decrease in reflectance due to washing. Useful.

  EXAMPLES Next, although an Example is given and this invention is demonstrated in detail, this invention is not limited to this at all.

Example 1
(A) Substrate (1) Raw material
(i) Raw material for forming a matrix: ordinary Portland cement 30% by mass, powdered silica 20% by mass
(Ii) Fiber raw material: 7% by mass of cellulose pulp
(Iii) Admixture: Wollastonite 17% by mass, calcium carbonate powder 26% by mass
(2) Manufacture Add water to the raw material, mix and mold with a round net paper machine to obtain a green plate, pressurize at a pressure of 24.5 MPa, perform autoclave curing at 180 ° C. for 10 hours, thickness 4 mm A hard calcium silicate plate having an apparent density of 1.6 g / cm ³ and a bending strength of 36 MPa was obtained. This hard calcium silicate plate was used as the substrate for the painted plate.

(B) Formation of impregnated sealer layer 1) Preheating The substrate was heated to a plate temperature of 66 to 67 ° C. in a blow type heating furnace.
2) Sealer application Sealer coating was performed with a roll coater (R / C) only on the decorative surface side (surface side) of a heated substrate (hereinafter, the substrate subjected to the treatment in each step is also referred to as a substrate). The sealer used was a mixture of “Alkali Sealer NY2” manufactured by China Paint Co., Ltd. and “urethane thinner SE” manufactured by the same company at a mass ratio of 1: 1. The coating amount was 20 g / m ² (organic solid content 5 g / m ² ).

(C) Formation of surfacer layer 1) Application of paint After applying a sealer to the surface of the substrate, immediately undercoating was performed using two R / Cs and one flow coater (F / C). The undercoat paint for R / C was prepared by blending “EP Coat No. 300SF White” manufactured by China Paint Co., Ltd., “51F” curing agent and “Retarder 1” thinner, respectively, at 16 kg / 1 kg / 3 kg. . The coating amount of R / C was 10 g / m ² per vehicle, and the total amount was 20 g / m ² (organic solid content 3.5 g / m ² ).
Next, paint immediately with F / C. As the paint, “EP Coat No. 300SF White”, “51F” curing agent and “Retarder 1” thinner made by China Paint Co., Ltd. were used. The paint was blended with paint, curing agent and thinner at 16 kg / 1 kg / 4 kg. The coating amount of F / C was 60 g / m ² (organic solid content 10.0 g / m ² ).
2) Intermediate drying process After performing F / C coating, it dried for 3 minutes with the ventilation type drying furnace which set the atmosphere setting to 50 degreeC. The coating film applied in this step was cured and dried to a state where it could be polished.
3) Fluff removal polishing process The coated surface after intermediate drying was polished using three roll buffing machines. First, the 240th roll is polished while being naturally rotated (forward rotation with respect to the substrate transport), and then the 240th roll is polished while being reversely rotated (rotation in the direction in which the brake is applied to the substrate transport). Finally, polishing was performed while rotating the # 1000 roll reversely. By this polishing, the fluff and foreign matter on the painted surface were removed, and the convex portions on the surface were made smooth and smooth. Since fine irregularities due to buffing are formed on the painted surface after the buffing step, adhesion with the top coat layer is improved.
4) Drying Step After the substrate was passed through a setting zone of 1 minute 30 seconds at an ambient temperature of 40 ° C., drying was performed for 15 minutes in an atmosphere of 78-80 ° C. using a wicket type blower dryer.

(D) Formation of overcoat layer 1) Preheating The substrate was heated to a plate temperature of 66 to 67 ° C in a blow-type heating furnace.
2) Top coating (a) Application of coating The top coating was applied by R / C only on the decorative surface side (surface side) of the heated substrate. The paint used was “Cerazex AAM-452” manufactured by Tsunewa Chemical Industry Co., Ltd., “Topcoat B liquid” manufactured by the same company, and butyl acetate as a thinner, 12.8 kg: 3.2 kg: 1 kg (mass ratio 4: 1: 0. What was mixed in 3) was used. The coating amount was 6 g / m ² (organic solid content 2.0 g / m ² ).
Next, coating was immediately performed with F / C. As the paint, “Cerazex AAM-454”, “Topcoat B liquid” curing agent, and butyl acetate manufactured by Hengwa Chemical Industry Co., Ltd. are used. The paint was blended at 12.8 kg / 3.2 kg / 0.5 kg of paint, curing agent and thinner. The coating amount at F / C was 80 g / m ² (organic solid content 27.2 g / m ² ).
(A) Intermediate drying step The top-coated substrate was dried in a drying furnace at 50 ° C to 60 ° C for 2 minutes and 30 seconds.
(C) Setting and drying After passing the substrate through a setting zone for 1 minute and 30 seconds at 40 ° C, drying was performed for 50 minutes in a 110 ° C atmosphere using a wicket-type air blow dryer.
(D) Cooling and unloading The substrate dried with the wicket dryer was cooled with a blower-type cooling device, and loaded with interleaving paper.

(E) Back glass cloth pasting process 1) Application of adhesive Turn the substrate up to the top coating process upside down with the decorative surface down and the base material surface up, and apply the adhesive to the base material surface using an R / C coating machine. Application was performed. As the adhesive, a two-component epoxy adhesive “E500W main agent” and “E500W curing agent” manufactured by Konishi Co., Ltd., mixed at 1: 1 were used.
First, the adhesive is applied by placing a substrate with a decorative surface facing down on an application jig in which a styrene foam cushioning material with a thickness of about 20 mm is laminated on a 9 mm plywood, and then roll-coating with the jig. The adhesive was applied to the entire base material surface on the top surface. The application amount of the adhesive was 80 g / m ² (organic solid content 36 g / m ² ).
2) Attaching the glass cloth Immediately after applying the adhesive, after placing the glass cloth "H201H107J" made by Unitika Co., Ltd. wound around the end of the substrate in a roll shape, the substrate was rolled to the opposite side, The entire surface was covered with a glass cloth, and the glass cloth was cut with a margin larger than the substrate. Next, it pressed from the glass cloth using the hand roll, and the board | substrate and the glass cloth were fully stuck. With this roll pressure, the glass cloth is pressed against the substrate surface, and the epoxy adhesive is infiltrated into the glass cloth. At the same time, the air mixed between the substrate and the glass cloth is expelled, and the edges of the cloth are stretched. Was lost.
3) Curing in the pressed state Next, the substrate was loaded and loaded with the slip sheet on the glass cloth. This interleaving paper was inserted for the purpose of fixing the substrates with an adhesive that protruded from each other or preventing the painted surface from being stained with the adhesive.
Next, a dummy plate was placed on the substrate so that an even pressure was applied to the loaded substrate, and a load of 0.3 kg / cm ² was applied from the top for 48 hours to cure the adhesive. .
4) Glass cloth shaping of edge part After the adhesive was cured, the substrate was taken out, excess glass cloth and adhesive that protruded around the circumference of the substrate were removed with a cutter, and then loaded again to obtain a coating plate for tunnel.

  The initial reflectance and post-washing reflectance of a coated plate using an organopolysiloxane-based paint as a top coat layer and a coated plate using acrylic silicon, urethane, or acrylic urethane were measured, and the change in reflectance was evaluated. The contamination test was conducted as follows.

(1) Contaminant A mixture of 32% by mass of Type 3 silica sand specified in JIS Z8901 test powder, 28% by mass of Type 11 Kanto Loam and 40% by mass of Type 12 carbon black is used as a contaminant. Use.
(2) Contamination test method About 1 gram of water is sprayed once by spraying on the coated surface of the test body having a size of 200 × 100 mm.
10 g of the pollutant is weighed out and sprayed uniformly on the surface sprayed with water using a sieve having an aperture of 0.5 mm.
Raise the specimen and tap the back of the specimen with a spoon to remove excess contaminants.
Using a cylindrical nylon brush rotating at 600 rpm and a sprinkling pipe that sprinkles 50 mL of water per second, it is washed once so that it passes under the brush in 3 seconds while sprinkling water on the painted surface. .
Lightly flush the specimen with water and dry with a blower at room temperature until there is no water on the painted surface.
Using a household sponge wet with water, lightly rub the painted surface passed through the brush, flush with water, and then dry the painted surface with a normal temperature blower.
(3) Evaluation Using a color guide sphere color difference meter manufactured by BYK Gardner, the reflectance of the painted surface before and after the contamination test is measured using the Y value (reflectance) of the Yxy color system.
Using a color guide sphere color difference meter manufactured by BYK Gardner, the color difference ΔE before and after contamination is measured using the L ^* a ^* b ^* color system.

The calculation method of the reflection retention (%) was set to (Y value after contamination / initial Y value) × 100 with respect to the Y value (reflectance) of the Yxy color system.
The closer to 100, the less the change in reflectance.

  The results are shown in Table 1.

From the results of Table 1, the coated plate of the present invention using the organopolysiloxane paint as overcoating layer, also not reduced reflectivity after washing, it was found anti Iho lifting rate is high.

The coated plate of Example 1 was subjected to a heat generation test according to JIS A5430: 2008 10.9 b) Annex JA. A corn calorimeter 3 manufactured by Toyo Seiki Seisakusho Co., Ltd. was used as a test apparatus, and the total calorific value at a heating time of 20 minutes was measured. As a result, the total calorific value of the coated plate is 7.1 MJ / m ² , and Table JA. It satisfies the condition that the total calorific value in heating time 20 minutes, which is the exothermic first grade judgment standard described in No. 1 exothermic judgment standard, is 8 MJ / m ² or less, and corresponds to the non-combustible material specified by the Building Standards Act did.

Claims (8)

A fiber-reinforced cement board is used as a substrate, and an impregnated sealer layer having an organic solid content of 1.3 to 7.5 g / m ^{2 on} one side of the substrate, a surfacer layer whose surface is polished, and an overcoat layer made of an organopolysiloxane-based paint A painted plate characterized by being laminated in order.   The coated board according to claim 1, wherein a non-combustible fiber cloth is bonded to the other surface of the substrate via an adhesive layer.   The coated plate according to claim 1, wherein an impregnated sealer layer is formed on the other surface of the substrate, and an incombustible fiber cloth is adhered to the surface of the substrate through an adhesive layer.   The coated board according to any one of claims 1 to 3, wherein the fiber-reinforced cement board has a thickness of 3 to 8 mm, an apparent density of 1.5 to 1.8 g / cm3, and an organic fiber content of 4 to 8% by mass. .   5. The total amount of organic solids contained in the impregnated sealer layer, surfacer layer, topcoat layer, adhesive and non-combustible fiber cloth is 39 to 180 g per unit area (m 2) of the substrate. Painted board according to item.   It is a coating plate for tunnel interiors, The coating plate of any one of Claims 1-5. The manufacturing method of the coating board characterized by including the process of the following (A) to (D).
(A) A step of preparing a fiber reinforced cement board as a substrate (B) An impregnation sealer is applied to at least one surface of the substrate to impregnate the substrate, and then the substrate is heated and dried to obtain an organic solid content of 1.3. ~7.5g / m on one surface of the substrate step (C) impregnating sealer layer is formed for forming the impregnation sealer layer ^2, after applying and drying the surfacer coating to form a surfacer layer by polishing the surface thereof Step (D) A step of forming an overcoat layer by applying an organopolysiloxane-based paint for the overcoat layer on the surfacer layer and then drying by heating. Furthermore, the manufacturing method of the coating board of Claim 8 including the process of following (E).
(E) The process of apply | coating an adhesive agent to the other surface of a board | substrate, mounting a nonflammable fiber cloth on it, and then pressurizing and bonding a nonflammable fiber cloth to a board | substrate