I mistakenly washed some mostly white towels with something red, now I have several pink towels. How come dye washes out of the original clothing so readily, but will now Not wash back out of my towels?

Question

It seems that the dye was lossely bound to the original clothing, but has bound much more tightly to my towels. There is no sign of the pink fading after several more washes.

Edit to add: I’m not looking for advice on how to get them whiter again, I can cope with pink towels! I am just curious as to why this happens.

In: Chemistry

Answer 1

So dye transfer can be caused by a bunch of stuff including excess dye left over from the manufacturing process, friction which can break down fibers and release dyes, washing in hot water which can break down the mordant and cause dye to leak.

Since the towels only got a little bit of dye there is no excess dye to leak off them, and if they were put in the dryer afterwards that would have heat set the dye. Over time they will fade due to friction/wear but it will take a long time because you only need a little bit of dye to change the color of white fabric. It could also be that the type of dye binds really well to the type of fabric in the towels.