abstract |
This invention relates to the use of sodium, calcium and ammonium salts of formic acid as early strength developers and setting accelerators in hydraulic cements, concretes, mortars and plasters. The salts used are acidic salts containing between 1.5 and 5 moles of the formate ion per mole of the cation. These salts have much greater solubility and are more effective than the corresponding calcium salts, particularly under low temperature conditions. |