Ultramarine pigments can be used in inks for most printing processes including hot-foil stamping. Letterpress, flexography and gravure need high-strength grades; lithography needs water-repellent grades; any grade is suitable for screen inks, fabric printing and hot-foil stamping. Improved strength grades presented in a high solids aqueous dispersion are finding increasing use in flexographic printing applications [3.167].
3.5.4.4