Method for the production of glass fiber-reinforced gypsum sheets and gypsum board formed therefrom
US4265979A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 1979 |
| Grant date | May 5, 1981 |
| Priority date | — |
| Expiry date | Nov 7, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24603
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A fiber-reinforced cementitious sheet is formed by first co-mixing in an air current reinforcing fibers such as glass fibers, and cementitious mineral materials in finely particulate form such as calcium sulfate hemihydrate, both in substantially dry form, depositing the mixture on a moving foraminous surface by means of the air current to form a sheet, applying water as by spraying in at least an amount which is stoichiometrically sufficiently to hydrate the calcium sulfate hemihydrate to the dihydrate form and to provide the necessary degree of plasticity to the mixture, densifying the sheet by compression, and setting and drying the sheet. A pair of sheets may be utilized as face sheets and, prior to setting, combined with a core formed of for example a calcium sulfate hemihydrate slurry, and the sheets and core then set and dried to form a paper-free gypsum board having excellent strength, surface hardness, and fire-resistant properties.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.