ACOUSTICAL CEILING BOARD

摘要

An acoustical ceiling board 2 in which both the decorative appearance of the ceiling board and its acoustical properties are produced by a series of grooves 4 cut in the board surface. The porosity of the board material and the amount of vertical exposed surface 6 in the decorative pattern gives a desired acoustical rating without the pin- punched or fissured perforations needed with most mineral fibre ceiling boards to secure the desired acoustical rating.