Building board and method for producing building board

Abstract

A building board includes an inorganic board having a surface covered by an insulating coating film containing a coating film forming material and organic hollow particles, wherein the organic hollow particles have an average particle size in the range of 5 to 50 μm and an average hollow ratio of 80% or more, and the insulating coating film contains 0 01 to 5.0 parts by mass of the organic hollow particles per 100 parts by mass of solid content thereof, and has an average thickness of 5 to 500 μm. The method for producing a building board includes: applying, onto a surface of an inorganic board, an insulating coating material containing a coating film forming material and organic hollow particles; and drying the insulating coating material to form an insulating coating film.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a building board that is suitable for wall materials, roof materials and the like, and a method for producing such a building board.[0003]2. Description of Related Art[0004]Conventionally, inorganic boards composed mainly of a hydraulic inorganic powder such as cement and wood reinforcement such as wood pulp fiber have been used. These inorganic boards have excellent physical properties including, for example, flexural strength, and thus are used as building boards such as interior wall materials, exterior wall materials, roof materials and the like of residential houses after they are subjected to coating.[0005]However, in view of the recent environmental issues, including, for example, those related to energy saving, there is a need for an improved thermal insulation effect for residential houses. To this end, investigations have been made to increase the thermal insulation effect for ...

AI Technical Summary

Benefits of technology

[0007]Therefore, it is an object of the present invention to provide a building board having excellent thermal insulation properties and design quality, and a method for producing the same.

[0008]The present invention provides a building board including an inorganic board having a surface covered by an insulating coating film containing a coating film forming material and organic hollow particles. The organic hollow particles have an average particle size in the range of 5 to 50 μm and an average hollow ratio of 80% or more. The insulating coating film contains 0.01 to 5.0 parts by mass of the organic hollow particles per 100 parts by mass of solid content thereof, and has an average thickness of 5 to 500 μm. Acrylic resin, silicone resin, fluororesin, acrylic silicone resin, polyurethane resin, epoxy resin, polysiloxane resin and the like can be used as the coating film forming material. Although any organic compound may be used as the material for the organic hollow particles, it is preferable that the organic hollow particles include at least one of acrylonitrile, methacrylonitrile, vinylidene chloride, acrylic acid ester, and styrene because the state in which the hollow ratio is high can be maintained. Further, it is preferable that the insulating coating film contains a water-soluble solvent because the coating film formed can easily be homogeneous in the process of forming the insulating coating film when the coating material forming the insulating coating film contains a water-soluble solvent. In that case, it is preferable that the water-soluble solvent includes at least one of a glycol-based solvent and a glycol ether-based solvent because these solvents contribute to homogenization. Examples of the inorganic board include ceramic siding boards such as a wood fiber-reinforced cement board, a fiber-reinforced cement board, a fiber-reinforced cement calcium silicate board and a slag gypsum board, metallic siding boards, and ALC boards. Ceramic siding boards are preferable because they increase the thermal insulation effect significantly. Furthermore, it is preferable that the insulating coating film is formed as an outermost layer in the building board in order to make the design quality of the surface of the insulating coating film pronounced.

[0009]The present invention also provides a method for producing a building board, including: applying, onto a surface of an inorganic board, an insulating coating material containing a coating film forming material and organic hollow particles; and drying the insulating coating material to form an insulating coating film. The method is characterized in that a coating material containing 0.01 to 5.0 parts by mass of organic hollow particles having an average particle size in the range of 5 to 50 μm and an average hollow ratio of 80% or more, per 100 parts by mass of solid content of the coating material is used as the insulating coating material, and the coating material is dried such that the insulating coating film has an average thickness of 5 to 500 μm. As the coating film forming material, it is possible to use, for example, acrylic resin, silicone resin, fluororesin, acrylic silicone resin, polyurethane resin, epoxy resin, and polysiloxane resin. It is preferable that the organic hollow particles include at least one of acrylonitrile, methacrylonitrile, vinylidene chloride, acrylic acid ester, and styrene. Further, it is preferable that the insulating coating material contains a water-soluble solvent because the insulating coating film formed can easily be homogeneous. In that case, it is preferable that the water-soluble solvent includes at least one of a glycol-based solvent and a glycol ether-based solvent because these contribute to homogenization. Examples of the inorganic board include ceramic siding boards such as a wood fiber-reinforced cement board, a fiber-reinforced cement board, a fiber-reinforced cement calcium silicate board and a slag gypsum board, metallic siding boards, and ALC boards. It is preferable to perform the production method of the present invention on ceramic siding boards because the thermal insulation effect increases remarkably. In order to make the design quality of the surface, of the insulating coating film pronounced, it is preferable that insulating coating film is formed as an outermost layer in the building board.

[0010]According to the present invention, it is possible to provide a building board having excellent thermal insulation properties and design quality, and a method for producing the same.

Problems solved by technology

As a result of in-depth studies carried out by the inventors, it has been found that one of the causes lies in that the ceramic fine powder tends not to provide a thermal insulation effect because its hollow ratio is prone to be low.

Additionally, the ceramic fine powder has a large particle size, and thus the surface of a coating film formed therefrom has no smoothness, resulting in a poor appearance in terms of design quality.