Process of producing dispersant free carbon black slurries and rubber masterbatches containing same

Claim 1

A PROCESS FOR PRODUCING RUBBER MASTERBATCHES COMPRISING THE STEPS OF: (A) COMBINING AT LEAST 7% BY WEIGHT OF CARBON BLACK WITH A LIQUID MEDIUM COMPOSED PRINCIPALLY OF WATER TO FORM A DISPERSANT-FREE SLURRY, (B) VIOLENTLY AGITATING THE COMBINED BLACK AND LIQUID UNDER CONDITIONS OF HIGH SHEAR UNTIL THE RESULTANT SLURRY ATTAINS AN APPARENT VISCOSITY OF AT LEAST 150 CENTIPOSIES, (C) SUBJECTING SAID AGITATED MIXTURE TO CONDITIONS OF MODERATE SHEAR, WHEREBY SAID SLURRY IS MADE READILY TRANSPORTABLE IN A CONCENTRATED FORM BY SUBJECTION TO PUMPING ACTION OF THE TYPE IMPARTING ONLY MODERATE SHEAR TO SAID SLURRY, (D) COMBINING THE RESULTING MIXTURE WITH LATEX, AND (E) COAGULATING THE RESULTING PRODUCT.