초록 ▼

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 foramino

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.

대표청구항 ▼

A cementitious laminated construction board having reinforcing fibers dispersed in the outer sheets thereof, said structural board being the product formed by the method which comprises: (A) forming a pair of cementitious sheets having reinforced fibers dispersed therein, each of said sheets being f

A cementitious laminated construction board having reinforcing fibers dispersed in the outer sheets thereof, said structural board being the product formed by the method which comprises: (A) forming a pair of cementitious sheets having reinforced fibers dispersed therein, each of said sheets being formed by: (a) mixing together in a moving air current generated by an air blower a substantially dry water-settable calcium sulfate hemihydrate in finely particulate form with reinforcing glass fibers, (b) providing a foraminous moving surface, (c) depositing the mixture of calcium sulfate hemihydrate and glass fibers on said foraminous surface to form a sheet (d) applying water over said sheet, (B) depositing an aqueous slurry of a water-settable calcium sulfate hemihydrate over one of said fiber-containing cementitious sheets, (C) placing the other of said fiber-containing cementitious sheets over the aqueous slurry, (D) permitting said cementitious sheets and said slurry to set, and (E) drying any excess water remaining in said construction board.