Electrophoretic display fluid comprising five types of particles

An electrophoretic fluid comprising a first type of particles, a second type of particles, a third type of particles, a fourth type of particles, and a fifth type of particles, all of which are dispersed in a solvent or solvent mixture, wherein:

• (a) the five types of particles are of colors differing from one another;
• (b) the first, second and third types of particles carry the same charge polarity;
• (c) the first type of particles is black in color, the second type of particles is non-white and non-black and formed of inorganic pigment, and the third type of particles is non-white and non-black and formed of an organic pigment, wherein the second and third types of particles are differently colored and have different surface chemistry, and wherein the first, second, and third types of particles carry different magnitudes of charge from each other;
• (d) the fourth and fifth types of particles carry a charge opposite to that carried by the first, second and third types of particles, wherein at least one type of particle includes a surface treatment.