Granular aminomethylenephosphonate

摘要

Aminomethylenephosphonate-coated granules of substantially water-insoluble silicate having improved stability in the presence of peroxygen compounds. Such coatings can comprise alkali metal aminomethylenephosphonate of the formula: <IMAGE> where each R is H, CH2PO3H2 or CH2PO3HM or CH2PO3M2; where M is an alkali metal; and n is 0 or an integer, preferably an integer of from 1 to 4. The coatings are substantially free of peroxygen compounds and peroxy compound precursors.