Gypsum Based Formulations
AssigneeBPB Limited
InventorsAgnes Smith, Thierry Chotard, Cyrielle S. Dupas, Ian Wilkes
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Abstract
The formulation for making plasterboard with paper cover sheets comprises finely divided gypsum, a minor amount by weight of starch and, as crosslinking agent for the starch, a tri-functional reactive s-triazine having substituents at positions 2, 4 and 6 of the triazine ring which are reactive with the starch. A preferred crosslinking agent is 2,4,6-trichloro-s-triazine, which is preferably partially reacted with the starch before further reaction with the paper cover sheets for the plaster board.
Claims13
A gypsum formulation, which comprises finely divided gypsum, a minor amount by weight of starch and, as crosslinking agent for the starch, a tri-functional reactive s-triazine having substituents at positions 2, 4 and 6 of the triazine ring which are reactive with the starch.
A method of producing plaster, which comprises mixing in water a finely divided gypsum, starch in a minor amount relative to the gypsum, and, as crosslinking agent for the starch, a tri-functional reactive s-triazine having substituents at positions 2, 4 and 6 of the triazine ring which are reactive with the starch, so as to form a slurry, and allowing the slurry to set.
A plaster board, comprising:
- a first cover sheet;
- a second cover sheet;
- and a core disposed between the first and second cover sheets, the core comprising calcium sulphate dihydrate, and a cross-linked starch in which the crosslinking agent is a tri-functional reactive s-triazine having substituents at positions 2, 4 and 6 of the triazine ring which have reacted with the starch.
Dependencies are inferred from the claim text.