I don't think they work because cp soap is a high PH and the colours aren't meant for high ph (alkaline).
But I haven't tried them and perhaps someone else has.
i dont know the brand, but if you go to the soap section, which is small, you will see soap color, they come 3 in a pack for like 3-4, the red will turn- hot pink, yellow- add alot, green and blue are good, purple ok. orange- is pale orange unless you add alot!
they do work better in hp, but work in cp, you can view some of my past pics. I do orange all the time and it turns peachy, red- hot pink etc. they stay.