hi neil
with the thread title as what 'lubricant' to use...
the silicone and teflon suggestions hit the spot.
the title and your 'stated' need aren't exactly the same.
a little back tracking on silicone...
first they were mis-named during the discovery phase, while thought to be related to another chemical grouping...
in reality the compounds are actually
siloxanes but the mistaken name '
ones stuck.
siloxanes contain NO OIL OR GREASE...
but oil or grease (or water or alcohols) can be the vehicle for the various siloxanes.
most folks that have had problems with siloxane sprays were using 'oil or petrol based products.
YOUR seals/gaskets are butyl based synthetic rubber, and probably have uv protection already IN the syn rubber formulation.
IF you wanna add topical uv protection (which may do very LITTLE to lengthen the lifecycle of the gaskets)
use one of these 2 products.
303
Sonus Total Eclipse
the 303 has the double utility of lubricant and protectant...
while sonus is VERY popular with auto detailing geeks...
like me.
these uv 'protectants' are often compared to spf 40, which of course is ANOTHER misleading and mis-useage of the term....
since the spf system and ratings is ONLY meant to apply to animal/people skin...
but i'm sure it helps sell the stuff.
cheers
2air'
i'm no chemist either, so if there is chemist who'd like to go into greater detail about 'silicones/siloxanes' or butyl rubbers, have at it!!!