| 摘要 |
<p>The present invention relates to acoustically porous building materials which are produced by disposing an aggregate material on the surface of a dry-formed web comprising a fibrous material and an organic binder, and consolidating the composite material such that the aggregate material is embedded in the web. The resulting product is acoustically porous but, in one preferred embodiment, the embedding process provides a substantially planar surface which is relatively non-friable.</p> |
