Patent ID: 8252200

Claim:
A dried water treatment composition exhibiting reduced chlorine loss during storage, comprising: calcium hypochlorite coated with a coating material comprising magnesium sulfate with an average hydrate number of about 4, said calcium hypochlorite being at least 70 wt. % anhydrous calcium hypochlorite; wherein said dried composition contains about 47 wt % to about 58 wt % available chlorine based on the total weight of said dried composition, and wherein said dried composition contains from about 9 wt % to about 11 wt % of hydrated water based on the total weight of said dried composition, and wherein said coating comprises from about 24 wt % to about 31 wt % of the total weight of said dried composition, and wherein said dried composition exhibits both reduced chlorine loss during storage and reduced oxidizing properties thereby qualifying as a non-Division 5.1 oxidizer or as a NFPA Class 1 or NFPA Class 2 oxidizer and; wherein said coating material further comprises one or more additional ingredients selected from the group consisting of water clarifiers, scale inhibitors, dispersants, water softeners, corrosion inhibitors, algaecides, fungicides, binders, and combinations thereof, and wherein said additional ingredients are present in an amount ranging from 0.1 to 5 wt %, based on the total weight of the composition.