The subject of the present disclosure is a process for dyeing keratinous material, in particular human hair, comprising the following steps:



applying an agent (a) to the keratinous material, wherein the agent (a) comprises:
(a1) at least one organic silicon compound selected from the group of silanes having one, two or three silicon atoms, and

(a2) at least one coloring compound comprising at least one effect pigment comprising α) a substrate platelet and β) a coating, wherein the coating comprises at least one layer that has been wet-chemically prepared using a metal alkoxide and an organosilicon compound having a basic group; and

applying an agent (b) to the keratinous material, wherein the agent (b) comprises:
(b1) at least one sealing reagent.