Dye migration or bleeding occurs when a soluble colorant such as a dye migrates out of a source medium (e.g. ink or paint) and into or through a absorbant layer or semi permeable – such as paper or fabric. Dye migration can result in stains in materials that are in contact with the dye source.
Dye migration requires a carrier for the dye to such as moisture. Dye migration is often the result of prolonged exposure to high humidity or water damage.
Example of dye migration in an animation cel through the interleaving tissue
The cel below (left) shows stains caused by the migration of a dye from a marker ink used to outline the image on the overlying cel. The dye has migrated through the interleaving tissue paper (right) and into the paint layer of the underlying cel.
Artwork for Holy Smoke by Monique Renault (2000). Paint, pencil and marker ink on cellulose acetate.