A process which includes treating, mixing, or contacting a Type I titanyl phthalocyanine with a weak acid with a pKa of at least equal to or greater than about 0; dissolving the acid treated Type I titanyl phthalocyanine in a solution of a trihaloacetic acid and an alkylene halide; adding the formed mixture to a solution of an alcohol and an alkylene halide thereby precipitating a Type Y titanyl phthalocyanine; and treating the Type Y titanyl phthalocyanine with monohalobenzene thereby resulting in a high sensitivity titanyl phthalocyanine.