uPVC Window cleaning products - black rubber smearing problem

I cleaned the exterior of my uPVC windows with HG powerful Cleaner for uPVC windows.. Whilst it did a perfectly OK job with loose-ish surface dirt, it made the rubber frame seals ' run' with black liquid, which then got all over the cleaning rags, my gloves, and went onto the white plastic. It more or less got INTO the plastic almost instantly and the cleaning fluid struggled to get it off. It just smeared the black over the frames. I then tried to use HG pVC Reviver, which simply polished the surface and removed some of the black, but didnt get rid of the smearing, which now seems to be part of the plastic! I then used all known combinations of vinegar, water, the HG cleaners, and soap., to no effect. Does anyone know another (non pVC ruining) method, or ever had this issue.??