An ink used in forming a functional layer of a self-luminous element by a printing method, the ink including a functional material and a mixed solvent. The mixed solvent includes solvents each having different vapor pressures. The functional material is dissolved or dispersed in the mixed solvent. A solvent that has a lowest vapor pressure among the solvents has a viscosity of at least 53 mPa·s, and a viscosity of the mixed solvent is 15 mPa·s or less.