US 7,026,084 : Cocrystals containing high-chlorine titanyl phthalocyanine and low concentration of titanyl fluorophthalocyanine, and electrophotographic element containing same


Molaire, Michel F. (Rochester, NY, US)
Kaeding, Jeanne E. (Rochester, NY, US)
Zubil, Theodore (Rochester, NY, US)
Murray, Jeffrey R. (Palmyra, NY, US)
Eastman Kodak Company (Rochester, NY, US) 

In a process for forming an amorphous TiOPc/TiOFPc pigment mixture containing a low concentration of TiOFPc, a mixture containing phthalonitrile and titanium tetrachloride is subjected to reaction conditions effective to form lightly chlorine-substituted crude crystalline Cl—TiOPc. The lightly chlorine-substituted crude crystalline Cl—TiOPc is combined with crude crystalline TiOFPc in a weight ratio from about 75:25 Cl—TiOPc:TiOFPc to about 99.5:0.5 Cl—TiOPc:TiOFPC to form a crude crystalline pigment mixture, which is treated under conditions effective to form a substantially amorphous pigment mixture of Cl—TiOPc and TiOFPc. The substantially amorphous mixture can subsequently be converted to a nanocrystalline Cl—TiOPc/TiOFPc pigment composition containing a low concentration of TiOFPc.