LIQUID ELECTROPHOTOGRAPHIC INK COMPOSITIONS
A method of producing a material with a perovskite structure on a substrate by liquid electrophotographic printing comprises: either liquid electrophotographically printing onto the substrate a composition comprising a dispersion of a salt AX and a thermoplastic resin in a carrier liquid; liquid electrophotographically printing onto the substrate a composition comprising a dispersion of a salt selected from BX2 and BX4 and a thermoplastic resin in a carrier liquid; and heat treating the printed compositions to form the material with a perovskite structure; or liquid electrophotographically printing onto the substrate a composition comprising a dispersion of a material with a perovskite structure and a thermoplastic resin in a carrier liquid to form the material with a perovskite structure; wherein A is a cation, B is a cation and X is an anion; wherein the thermoplastic resin comprises a copolymer of an alkylene monomer and a monomer having acidic side groups.