Thin, sealant-coated, fiber-reinforced gypsum panel
US5637362A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Jun 10, 1997 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/91
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for making a thin, sealant-coated, fire and indentation resistant gypsum panel. A layer of a mixture of cellulosic fibers moistened with water and an additive to restrict the adhesion of cellulosic fibers to one another, is deposited on at least two separate conveyors to form a fibrous matt on each conveyor. A layer of dry calcined gypsum containing set accelerator is deposited on the fibrous matt on each conveyor which contains, by weight on a dry weight basis, about 70-90% gypsum, about 10%-19% cellulosic fiber and about 1%-9% of combined additive and set accelerator. Each layer on each conveyor is directed to a mixing station to form a homogeneous layer, and the formed homogeneous layers on separate conveyors are placed atop one another on a single conveyor to form a combined homogeneous layer. Water is added to the layer or layers to rehydrate calcined gypsum. The combined homogeneous layer is subjected to pressure to form a pressed, homogeneous fiber-reinforced gypsum panel, and dried. The surface of the dried panel is sealed with wax-free, water resistant sealant. Sealant-coated, fire resistant, indentation resistant gypsum panels having a thickness of about 0.25 in…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.