Dye migration and colour bleeding
The colour of the thing you are cleaning can move too. Every trade body that publishes a stain procedure opens by telling you to test for it.
In detail
A dye is held in a fibre or a coating by an attachment that a cleaning solution can weaken. When it does, the colour leaves where it was and goes somewhere else — into the cloth, into the water, or into the pale part of the same item. This is the risk that every serious stain procedure addresses before it addresses the stain: the carpet trade instructs pretesting any solution in an inconspicuous area for colour transfer or damage, and specifies a WHITE cloth throughout precisely so that no dye travels the other way, out of the cloth and into what is being rescued. Several sources name the specific agents that do it. Ammonia, used improperly, can cause a colour change, so a hidden area must be tested. Silk dyes are described as not reacting well to water, with home washing able to make colours fade or run, especially where light and dark are combined in one garment. On suede, cleaning agents will immediately darken nude leather — a colour change with no stain involved at all. Oxidising bleaches are the same mechanism deliberately: they destroy a chromophore and cannot tell the stain's from the fabric's.
Why
- Suede is explained by Dye migration and colour bleeding
- Viscose and rayon is explained by Dye migration and colour bleeding
- Silk is explained by Dye migration and colour bleeding
- Hair dye is explained by Dye migration and colour bleeding
- Food colouring is explained by Dye migration and colour bleeding
- Carpet is explained by Dye migration and colour bleeding
- Dye transfer is explained by Dye migration and colour bleeding
Sources for this page
Sources
Spot Solver: spot and spill removal procedures
The Carpet and Rug Institute (CRI) · Trade or professional body
Relied on for: That any spot removal solution is pretested in an inconspicuous area for colour transfer or damage, that a white cloth is specified so no dye transfers into the carpet, and that ammonia used improperly can cause a colour change. (states this directly)
Drycleaning & Laundry Institute International (DLI) · Trade or professional body
Relied on for: That some silk dyes do not react well to water and that home washing can cause colours to fade or run, especially where light and dark colours are combined in one garment. (states this directly)
Leather Care and Cleaning Guide
The Leather Institute, 2011 · Trade or professional body
Relied on for: That cleaning agents will immediately darken nude leather. (states this directly)