Soap, soap suds and lather

[kaylasdad99]

This might have something to do with optics.

All of the bar soap I’ve ever seen and used (with the exception of Ivory) is made with dye in it. This lends a bar of soap a distinctive color. But when I use a bar of soap, the suds and lather produced is uniformly white. Why doesn’t the dye in the soap impart some color to the teeny-weeny bubbles that show up?

[susan]

The Teeming Millions have been here before:

Why are soap bubbles always clear white?

A friend (seems no one else has the nerve to ask these questions here) has wondered often why soap bubbles are always white (clear) regardless of the color of the sudproducing liquid, e.g. purple bubble bath. Any ideas?

How does colored soap become white?

Here’s a question my kid asked me which had me stumped. How does liquid soap and shampoo turn white when lathered no matter what color it was before and why doesn’t the coloring agent stain the skin?