lignin of sulfate or sulfite pulp mill liquors the most preferred lignosulfonates are the metal or ammonium salts particularly the alkali or alkaline earth metal salts such as sodium potassium magnesium and calcium these materials are water soluble and form hard durable protective films when dried the preferred lignosulfonate is sodium lignosulfonate the filler component of the protective overcoat includes carbon black pigments such as tio 2 silica alumina aluminosilicates and many of the clay type mineral materials which are commercially available including talc calcium carbonate diatomaceous earth bentonite kaolin wollastonite dolomite gypsum pyrophyllite and phosphorite as well as mixtures of different filler types preferred fillers are minerals processed to have an average particle size in the range of from about 0 1 to about 50 microns the most preferred filler material is talc hydrous magnesium silicate having an average particle size less than 20 microns preferably less than 10 microns the controlled release cr material substrate encapsulated in the controlled release coating may be overcoated with the protective coating by sequential application of an aqueous solution of the lignosulfonate and the finely divided mineral filler to a tumbling or moving mass of the cr material in a rotary drum pan ribbon or paddle mixer or by fluidized bed techniques as described above for.