An embodiment of the present invention will be disclosed below. A bank substrate comprising: a substrate and a bank on the substrate, wherein a surface energy of the bank is 30 to 45 mJ/m2. Further, colored pixels are present between zones of the bank, and the difference of height within a pixel of the colored pixels is 0.3 μm or less. The colored pixels comprise colored inks, and a viscosity of the colored inks is 50 mPa·s or less.