Charge transport ink composition

Abstract

This invention provides a charge-transfer ink composition that exhibits excellent dispersibility of metal oxide nanoparticles in organic solvents and provides a practical charge-transfer thin film. The composition comprises metal oxide nanoparticles, oxides of metals selected from the group consisting of Zn, Mg, Ti, Zr, Sn, Ga, Fe, Ta, Nb, Y, Mo, W, Pb, In, Bi, and Sr, and salts composed of one or more metal oxide nanoparticles from the group consisting of at least two complexes of the aforementioned metals, a cation represented by formula (A2-3), and an anion represented by formula (B1-1), wherein the difference (ΔMolLogP) between the cation and the anion, expressed as "MolLogP(cation) - MolLogP(anion)", is greater than -3.0, and an organic solvent.