Cleaning Kodak Polycontrast Filters?

[neil poulsen]

What's a good way to clean Kodak polycontrast filters? Is there a solvent that won't ruin the surface? I believe these are acetate.

[Louie Powell]

I think some of the older polycontrast filters could have been gelatin - and I don't think you would want to use any liquid on them. Just wipe them using a soft, dry cloth (well washed underwear?)

But the newer versions were acetate, and water should be OK.