I am trying to see why my new "granite composite " white sink has a sticky residue after soaking the sink in bleach for a several hours. White is coming off from the sink I believe and sticking on the dishes, utensils. I used " good off" to clean the sink and it took the residue off. I cannot find the maker of the sink on line,

Just a guess - a heavy wax, possibly a synthetic one, was applied to cut down on scratches during delivery and installation. Soak it and dishes etc in very hot soapy water and it should be gone.

You should have received a manufacturer warranty from the seller. This kind of warranty can be hard to get, at times, though. On housing items like new roofs you do not buy without such a warranty. It does sound like an acrylic wax of some kind, or what they used to bond the pieces of rock to make "granite." I thought those sinks were all custom made.