Originally Posted by
joyce888
...I would be very careful about using chemicals and maybe getting it into the working parts...
I agree, it has to be done carefully, but the gel like consistecy of these brighteners have been used successfully on computers, phones, sewing machines. It hasn't seeped into the inners of the items, and pvc stand up very well to peroxide and laundry detergents like oxiclean. There's always a risk involved, but the worst brownish yellowing that can happen I just can't live with. It's a bit messy, but not much worse than polishing copper and silver.