Pigment powders are inert colorant with no binding power of their own. To use pigments, a binder or sealer must be employed to allow them to adhere to a surface. This is achieved either by mixing pigments into a binding medium (such as paint) or using a clear sealant on top of the pigment once it is applied to a surface. They can also be suspended into translucent or transparent materials.
Because inorganic pigments are inert, they will not chemically react with other materials. Therefore they can be used in water, oil or chemical based products.
There is a distinct difference between pigments and dyes. A dye will dissolve within a medium whereas a pigment disperses in the medium as very fine particles. The amount of pigment to add into a base depends upon the color desired and the medium used. A clear or translucent medium will provide a saturated color and an opaque one will provide a tint (lighter version) of the pigment color.
Each medium has a saturation limit. This is the maximum amount of pigment that can be added before the binding quality or mechanical stability of the medium is compromised. This saturation limit varies by medium.
Prepare pigments by slaking (soaking) in an equal amount of water and mixing into a smooth paste to ensure pigment particles have complete dispersed. If you wish to limit the amount of extra water this would add to a recipe, then use a mix of 50% alcohol and 50% water. You can use methyl alcohol, or for a nontoxic alternative use Everclear grain alcohol instead. Vodka can also be used in water-based mediums to slake pigments.
Oil, Solvent or Alcohol-based Mediums
Prepare pigments by mixing into an equal amount of a solvent that is suitable for the medium, or into a small amount of the medium itself. Mix into a paste to ensure the pigment is completely dispersed within the solvent or medium. Mix this paste completely into the remaining medium.
Dry Powdered Mediums
For dry powders such as plaster or milk paint powder, pigments can be added using the water-based method
For small quantities pigments can be mixed directly with the dry powder. Place the desired ratios of pigment and powder into a covered container (jar, coffee can, etc) close lid tightly and shake vigorously until pigment is dispersed and has colored the powder. Proceed with your usual recipe.
Mixing Small Quantities
For fine art uses such as acrylic paint, egg tempera, oil paint, glues, etc, pigments can be mixed directly with the medium for immediate use from the artist's palette.
Full instructions for mixing pigments are provided in our extensive Recipe Library. Don't see what you are looking for? We're here to help.