The invention relates to a process for the preparation of coated granular sodium percarbonate having a low TAM value. The preparation is carried out by fluidized-bed spray granulation at a temperature T.sub.G in the range from 45 to 75.degree. C., and the coating is effected by the spray application of an aqueous solution containing at least one coating component in a fluidized bed at a temperature T.sub.U in the range from 35 to 100.degree. C. According to the invention, a) after the fluidized-bed spray granulation but before the coating, drying is carried out at T.sub.NT of greater than T.sub.G, or b) the fluidized-bed granulation is carried out in at least two steps at T.sub.G1, T.sub.G2 . . . T.sub.Gn, T.sub.G2 or T.sub.Gn being higher than T.sub.G1, and drying being unnecessary if 2/3 of the granulate have been formed at T.sub.G1, or c) drying takes place not after the granulation but after the coating, at T.sub.UNT, T.sub.UNT being at least 20.degree. C. higher than T.sub.G.

 
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