Hello, I am a leather repair tech who has had an opportunity to do some work on boat seats. The main problem is lots of both black spots and blotchy dark areas on a cream colored vinyl. I assume it is mildew. The boat owner claimed it was spider poop and he seemed to be serious. No kidding. I tried cleaning with SEM soap and 303 fabric/ vinyl cleaner which removed about 50%. Is there a product/technique that might give better results or remove the remainder?
I attempted to remove some black spots with acetone on a q-tip. Took a number of strokes, but removed spots along with some of the color. Not a viable option. Didn’t try naptha.
On the final photo, I cleaned above the seam and below the seam was untouched.
Thanks for any suggestions.