Process for preparing quinacridones
AssigneeCiba Specialty Chemicals Corporation
InventorJames B. Ganci
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Abstract
This application relates to a process for preparing quinacridones whereby the corresponding dihydroquinacridone is oxidized by subjecting a paste containing the dihydroquinacridone and an oxidizing agent to a high shear force mixing step.
Claims21
A process for preparing an unsubstituted or substituted quinacridone from a correspondingly substituted dihydroquinacridone, which process comprises subjecting a paste containing the dihydroquinacridone and an effective oxidizing amount of an oxidizing agent which is an aromatic compound containing a nitro group or a quinone compound plus molecular oxygen, in the presence of an effective reaction-facilitating amount of a strong base, to a high shear force mixing step.
Dependencies are inferred from the claim text.