Abstract: The invention relates to a cationically curable composition with at least one cationically polymerizable component, a first photoinitiator releasing an acid when irradiated with actinic radiation of a first wavelength ?1, and a second photoinitiator releasing an acid when irradiated with actinic radiation of a second wavelength ?2, wherein the second wavelength ?2 is shorter than the first wavelength ?1, and wherein the second photoinitiator, after irradiation of the composition with actinic radiation of the first wavelength ?1, shows an absorption of actinic radiation of the second wavelength ?2 in the composition that is sufficient to activate the second photoinitiator and fix the composition. Furthermore, a method is described for the joining, casting, molding, sealing and/or coating of substrates using the cationically curable composition.