| 摘要 |
<p>A curable gypsum-based composition for the production of cured gypsum matrix, the composition comprising a two-component composition comprising: (a) a first component comprising calcined gypsum suspended in water, and a set retarding substance comprising (i) an organic acid containing at least two acid groups selected from the group consisting of carboxyl, sulphate, sulphonate, phosphate or phosphonate, said acid optionally also containing at least one hydroxy group per molecule; and/or (ii) inorganic anions selected from the group consisting of polyphosphate and polyborate, or mixtures thereof, and (b) a second component comprising a set accelerating substance comprising water-soluble salts of multivalent metal ions. The water soluble salts in component (b) forms stable precipitate or complexes with the acid in component (a). The component (b) may also comprise easily soluble salts of ammonium and/or cations from the first group of the periodic table of the elements, which will accelerate the hardening process.</p> |
