I am looking for a backing that can be sprayed or painted onto the underside of a bathroom rug or mat that is perfectly good on top but where the latex on the back has disintegrated into powder. There used to be a product like that but I can no longer find it.
As far as I know, the latex rubber spray is no longer readily available at Building Supply stores.
You may want to consider using a rubber non-slip waffle pad under your mat that will accomplish the same thing and keep it from slipping. It is however, a separate piece. This type of no-slip under-pad is available at most flooring and hardware stores.