| 摘要 |
PROBLEM TO BE SOLVED: To eliminate a coating material having creeped around to a rear surface by preventing peeling off to be caused by breakage of a base material of a coated surface by using a rigid cemented chip board obtained by kneading a chopped wood material and water with a raw material comprising a thermosetting cement composition being under a specific condition and thermally pressing. SOLUTION: After applying a water-based coating material 2 in excess to a surface of a rigid cement chip board 1, the excess coating material is removed by blowing air 3 onto the coated surface. The board 1 to be used comprises a thermosetting cement composition wherein 0.2 to 2.0 pts.wt. of an alkali metal salt of an organic carboxylic acid is added to 50 to 96 pts.wt. of Portland cement, 2 to 25 pts.wt. of alumina cement, 10 pts.wt. of slaked lime, 1.5 to 15 pts.wt. of unhydrous gypsum or/and hemihydrate gypsum, and the others. The organic carboxylic acid is citric acid, maleic acid, gluconic acid, or the like, and the alkali metal salt is a sodium salt, or a potassium salt. Chopped wood material and water are kneaded with this raw material, and the board 1 is obtained by thermal pressing.
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