US Patent 11679408 Printing system and method

There is disclosed a method of printing onto the surface of a substrate, which method comprises i) coating a donor surface with a monolayer of particles, ii) treating the substrate surface to render at least selected regions tacky, and iii) contacting the substrate surface with the donor surface to cause particles to transfer from the donor surface only to the tacky regions of the substrate surface. After printing on a substrate, the donor surface returns to the coating station where the continuity of the monolayer is restored by recovering with fresh particles the regions of the donor surface exposed by the transfer of particles to the substrate.