I painted on silk many years ago. It was a lot of fun!
What I remember, though, is that it is somewhat tricky to set the dyes in silk; otherwise they wash up as pastels. Setting requires a specialized steaming process. I knew someone who did the steaming at home (she was making silk scarves for sale at a Waldorf school); I believe it required rolling the silks in newsprint and had to steam the silks for a couple of hours.
At one time I took a class and used paints that could be heat set with an iron. Used resist to keep the colors separate.
Unfortunately, I do not remember any of the brand names anymore.