초록 ▼

Perforations of a board for building material are formed by a number of recesses (13), or a number of recesses (13) and through-holes (12). A bottom face (16) of the recess forms a face for screwing or driving the fixing element (70) thereto. A color of the bottom face is set to have a brightness of

Perforations of a board for building material are formed by a number of recesses (13), or a number of recesses (13) and through-holes (12). A bottom face (16) of the recess forms a face for screwing or driving the fixing element (70) thereto. A color of the bottom face is set to have a brightness of color decreased in comparison with a color of a surface (18) of the board. A substrate of the board is a gypsum board and the bottom face of the recess is formed by a liner paper for gypsum board. According to such a board, a region for screwing or driving the fixing element thereto can be ensured without impairing regularity, uniformity or architectural design of the perforations, and putty finishing or the like for an exposed part of the fixing element can be omitted.

대표청구항 ▼

The invention claimed is: 1. A board for use as a building material with a fixing element having a head, the board comprising: a gypsum board formed with a gypsum core; a first sheet of liner paper applied to the gypsum board to define a first surface; a plurality of perforations disposed on the fi

The invention claimed is: 1. A board for use as a building material with a fixing element having a head, the board comprising: a gypsum board formed with a gypsum core; a first sheet of liner paper applied to the gypsum board to define a first surface; a plurality of perforations disposed on the first surface of the board, the perforations being constituted from a number of visible recesses, or a number of visible recesses and visible through-holes, the perforations having a shape that is a polygon or a circle, and said visible recesses being formed on the first surface of the board by compression-forming for locally compressing the gypsum board, and wherein each recess has a visible bottom face that is exposed and formed by the first sheet of liner paper continuously extending from the liner paper on the first surface of the gypsum board without breakage, the bottom face of each visible recess providing a face to be secured by the fixing element thereto, and the exposed head part of the fixing element being contained in the recess. 2. The board as defined in claim 1, wherein a bottom face has a first color and the first surface of the board has a second color, the first color having a brightness of color decreased in comparison with the second color. 3. The board as defined in claim 1, wherein the recesses and the through holes have a predetermined ratio to create a predetermined sound absorption characteristic of the board. 4. The board as defined in claim 1, further comprising a second sheet laid over the through-holes on a reverse face side of the gypsum core to provide a second surface. 5. The board as defined in claim 4, wherein said second sheet is a sheet including glass fibers and inorganic matter. 6. The board as defined in claim 1, wherein the bottom face of a recess has a positioning index for positioning the fixing element, which has a tip. 7. The board as defined in claim 6, wherein said positioning index is a dent, a small aperture or a cross-shaped groove, into which the tip of the fixing element can be inserted. 8. The board as defined in claim 6, wherein said positioning index is positioned at a center of the bottom face. 9. The board as defined in claim 1, wherein a depth of a recess from the first surface of the board is set to be in a range from 0.1 mm to 2.0 mm. 10. A method of producing the board as defined in claim 1, wherein the surface of the board is locally pressed by a flat pressing face of a male die so that the recess of a predetermined depth is formed on the first surface of the board and the recess is provided with the bottom face of the recess for screwing or driving the fixing element thereto; and wherein the depth of the recess is set to be in range from 0.1 mm to 2.0 mm. 11. The method as defined in claim 10, wherein a guide plate provided with a guide hole for inserting the male die there into and an abutment face for abutment against the first surface of the board is used, and the pressing face of said male die is pressed against the first surface of the board such that the abutment face is in contact with the first surface of the board. 12. The method as defined in claim 10, wherein a penetrating member which has a profile substantially conforming to an outline of the recess and which transitionally penetrates the first surface of the board for facilitating deformation of the first surface is used. 13. The method as defined in claim 10, wherein the first surface of of the board is colored before forming a recess or through hole in the board in a color matching the bottom face, and after the recess of the predetermined depth is formed, the first surface of the board is colored in a color brighter than the color of the bottom face. 14. The method as defined in claim 10, wherein the method further comprises boring the through-holes through the board. 15. A method of installing the board as defined in claim 1, wherein a sound absorption effect and an acoustic reverberation effect are established with use of first boards which are said boards improved in their sound absorption performance by control of a ratio of the recesses and the through-holes, and second boards which are said boards restricted in their sound absorption performance by control of the ratio of the recesses and the through-holes. 16. The method as defined in claim 15, wherein the recesses and the through-holes have equal dimensions.