Concrete dye
A very fine, highly soluble colorant that penetrates deeply into concrete for intense, uniform color. Common on polished floors, where stains often cannot penetrate.
What does concrete dye mean?
Dyes come in solvent-based versions that give vivid, deeply penetrating color and water-based versions that produce softer tones. Their major limitation is UV stability, so most are interior-only products that fade outdoors. Because they penetrate rather than react, they can color densely finished and polished surfaces that reject other colorants.
In practice
The saturated colors on polished retail and restaurant floors are usually dye applied between grinding steps.