Formulation of Pigment Preparations
Two issues dominate the formulation of aqueous dispersions, namely environmental considerations and multicompatibility.
Traditional aqueous pigment dispersions consist of:
 | the pigment, generally at a high a loading as possible |
| a surfactant, often based on nonyl phenol ethoxylates |
| a humectant, formerly monoethylene glycol, later propylene glycol |
| biocide, originally pentachlorophenol, but then replaced by a number of complex alternatives |
| water |
Occasionally other products such as thickeners and anti-foams may have been included.
Pigments
Pigments generally pose little threat either with regard to their physiological or environmental properties. Pigments based on prohibited heavy metals have not been used in water based paints or inks for many years. There are concerns about copper, but the metal in copper phthalocyanine is tightly bound and bio-unavailable, so it poses little or no risk.
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