Those 3M films are mainly a polyurethane
. Manufacturing polyurethanes apparently is a rather expensive business due to associated pollution and toxic chemical issues, I'm told that is why Vredstein stopped making some damned fine sea boots 20 years ago.
But in any event, in the US, once you start building in "biocides" the EPA gets involved, and you have to deal with pesticide regulations
, and life gets doubly complicated. For a product that is NOT designed for constant immersion in water.
Better to put the poison in a clear "varnish" and just paint
it on, since there won't be much gravel damage to worry about on most boats.(G)
Kinda boring the way that stain is always yellowish, isn't it? I'd rather see someone figure out a way to make it glow blue at night. Then at least, it would be ornamental.
Or glow red on the one side, green on the other, and supplement the nav lights.(G)