A: Detergent compositions containing sodium percarbonate are known in the art. Sodium percarbonate is an attractive perhydrate for use in detergent compositions because it dissolves readily in water, is weight efficient and, after giving up its available oxygen, provides a useful source of carbonate ions for detergency purposes. However, the inclusion of percarbonate salts in detergent compositions has been restricted by the relative instability of the bleach both as is and in use. Sodium percarbonate loses its available oxygen at a significant rate in the presence of ions of heavy metals such as iron, copper and manganese and also in the presence of moisture, these effects being accelerated at temperatures in excess of about 30.degree. C. To solve this problem, several solutions have been found.

1. Sodium percarbonate is coated with a hydrophobic substance or the like.

2. Magnesium silicate is incorporated in a detergent composition containing sodium percarbonate.

3. A chelating agent which forms an easily water-soluble metal chelated compound such as nitrilotriacetate (NTA) or ethylene diamine tetraacetate (EDTA) is incorporated in a detergent composition. 

4. Zeolite A is replaced by maximum aluminium zeolite P (zeolite MAP) since zeolite MAP itself is of greater liquid carrying capacity than zeolite A. 

5. The elimination of impurities, such as heavy metals which catalyze the decomposition reaction during detergent processing, alleviates the instability of aqueous SCP solutions.

6. Provide sufficient sodium carbonate in the composition to be able to combine with all of the available water in the composition to form sodium carbonate monohydrate, the term "available water" includes water chemically available as hydrogen peroxide, water of crystallization of sodium carbonate hydrates and free water which may temporarily exist in the composition.