| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a porous ceramic sound absorber having an excellent sound absorption characteristic and weather resistance, being particularly resistant to fouling, and easy to clean even when fouled, maintaining its good appearance over a long period. SOLUTION: The sound absorber is made of a ceramic block obtained by adding a combustible porosity imparting material to refractory clay and/or refractory chamotte and baking the mixture, the ceramics block having communicating pores with chief pore diameters from 0.2 to 2000μm, and a permeability of 1 cm3.cm/cm2.sec.cmH2O or more. The ceramic block has a number of sound absorbing holes or grooves bored in its surface, and only the surface is glazed while the inner peripheral surfaces and bottom surfaces of the sound absorbing holes or grooves are left intact to provide the surface with a substantially air-impermeable layer of glaze with the communicating pores filled.</p> |
