The paste should be pre-soaked in co-solvent at a paste:solvent ratio of between 1:1 to 3:1. When formulating aqueous inks, the pH of the system should be kept as close to neutral as possible. Pre-soaking generally takes from one to eight hours. Finer grades typically take longer than coarser grades. Use low shear, slow speed mixing to achieve a smooth consistency free of agglomerates. High shear dispersion techniques should be avoided, as they will distort the aluminum flakes.