| 摘要 |
An abuse-resistant, cast acoustical ceiling tile having improved impact resistance and excellent sound absorption values. The ceiling tiles have aggregate particles applied to the surface of a wet pulp in the casting process and the particles are embedded in the pulp by compression with a roll and/or smooth plates. The aggregate particles have an average particle diameter of at least about 1,000 microns. The ceiling tiles have excellent sound absorption properties with a noise reduction coefficient (NRC) of at least about 0.50. Calcium carbonate is the preferred aggregate particle material. |
