A process for forming a cocrystalline mixture of titanyl phthalocyanine (TiOPc)
and titanyl fluorophthalocyanine (TiOFPc) includes: dry milling a mixture of crude
TiOPc and crude TiOFPc, thereby forming an amorphous pigment mixture of TiOPc and
TiOFPc; and heating the amorphous pigment mixture at a temperature effective to
form a cocrystalline composition comprising titanyl phthalocyanine (TiOPc) and
titanyl fluorophthalocyanine (TiOFPc), the cocrystalline composition being characterized
by an X-ray diffraction spectrum exhibiting intensity peaks at 7.2, 12.9,
16.3, 22.3, 24.6, 26.2, and 28.8 with respect to
X-rays of Cu Kat a wavelength of 1.54 1 of the Bragg angle 2.