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Name: David
Status: educator
Grade: 4-5
Country: USA
Date: Fall 2009


Question:
What are the best pigments to use for making crayons that are in bright colors, not earth tones? Are organic pigments suitable or is another kind of pigment or dye? It is very hard to find out which kind of pigments to use. Can you help?



Replies:
Though it may not appear so, crayons are a highly formulated product. Just mixing a pigment and wax does not make a crayon. 1. The pigments are dusty powder, usually, so you need a air handling system to keep you and the whole room from being covered with pigment dust. 2. The pigment needs to be "ground", that is, mixed with the molten wax under a high shear. This requires specialized equipment -- extruder, two roll mill... 3. The selection of pigment must be considered. The pigment must have the shade. This may require several pigments to be "ground" into the crayon to get the "right" color. The pigment must be non-toxic (no lead, cadmium, or other "heavy metal" pigments. And these are just the short list of requirements.

Making crayons is not a project to be undertaken by the amateur. As I said, they are complex formulated products.

Vince Calder



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