Patent ID: 8608847
Filing Date: 2013-12-17
Classification: C04B

Abstract:
1. A method for the production of a setting and hardening accelerator for hydraulic binders, comprising the steps of: (i) reacting a calcium compound CV with a silicon compound SV; and (ii) adding a phosphonic acid derivative having the formula (I) wherein X stands for H wherein R R R R wherein the substituent A, independent of one another, stands for a C2 to C4 alkylene group, q is a value from 2 to 300 m is a value from 1 to 4 n is a value from 0 to 1, wherein the calcium compound CV is selected from the group consisting of calcium chloride, calcium nitrate, calcium formiate, calcium acetate, calcium bicarbonate, calcium bromide, calcium citrate, calcium chlorate, calcium hydroxide, calcium oxide, calcium hypochloride, calcium iodates, calcium iodide, calcium lactate, calcium nitrite, calcium phosphate, calcium propionate, calcium sulfate, calcium sulfate-hemihydrate, calcium sulfate-dihydrate, calcium sulfide, calcium tartrate, calcium gluconate, calcium sulfamate, calcium maleinate, calcium fumarate, calcium adipate, and calcium aluminate, and the silicon compound SV is selected from the group consisting of sodium silicate, potassium silicate, lithium silicate, water glass, silicic acid, sodium metasilicate, potassium metasilicate, di-sodium metasilicate, di-potassium metasilicates, silicon dioxide, di-sodium disilicate and di-sodium trisilicate.