Initiator molecule for a nonlinear absorption reaction, photopolymerizable composition activatable by two-photon absorption, and associated 3D printing process.

摘要

The invention relates to a polymerization initiator molecule, capable of being excited by two photons and of generating polymerization initiator free radicals, molecule characterized in that it comprises two branches grafted onto a central phenyl nucleus, each branch comprising an oligomer of oligo-phenylenethynylene-yl type or oligo2,5-dihalogenophenylenethynylene-yl type. The invention also relates to a photopolymerizable composition which can be activated by two-photon absorption, composition comprising: - a resin which can be polymerized by the radical route and - a radical photoinitiator system in a photochemically effective quantity, composition characterized in that the photoinitiator system comprises at least one initiator molecule such as described above. Finally, the invention relates to a method and an associated device for two-photon three-dimensional printing comprising a step of transforming a volume of a photopolymerizable composition comprising at least one initiator molecule, transformation by irradiation of said volume of composition by a light irradiation source emitting an irradiation signal having a wavelength Lirr comprised between 1 and 1.5 times, and preferably between 1.1 and 1.25 times, an LC cut-off wavelength utOff of the initiator molecule. Application to two-photon 3D printing at submicron resolution.