1 октября, 2015 
Malyar These are generally higher in viscosity than the emulsions and are used for specific purposes. A volatile amine is used for neutralisation. When it leaves the film, the film becomes insoluble. These materials, especially viscosity modifiers, dissolve as the pH changes. As a general rule an acid value of 50mg KOH/g is required in order to obtain a usable dispersion upon neutralisation. Dispersions have been designed for the following uses;
• Viscosity modifiers — to control the viscosity of the finished lacquer.
• Pigment wetting — emulsions are generally poor at wetting pigments and cannot be used at the high shear rates employed in pigment dispersions.
• Flow and gloss improvers — flow and gloss of emulsions tend to be low because of their particulate nature, but these materials can significantly improve them, with little or no effect on resistance properties. [11]
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