Composite fiberboard and process of manufacture

摘要

A novel composite board of mineral wool, perlite, and cellulosic newsprint fibers for use primarily as a ceiling tile is disclosed. The board displays virtually no sag (less than 200 mils) when exposed to high temperature and high humidity while displaying quite acceptable strength. The board is manufactured by selective deposition of a composition of latex and extender particles on the cellulosic newsprint fibers.