"True "water-proof" charts would be made with sized wood fibre paper, subsequently surface sized."
So it is true that Canada
is so primitive you've never had true water-proof charts up there? In the US they are printed on plastic stock, similar to DuPont Tyvek, sometimes other latex-based sheets
, but there's no wood or plant fiber used in our waterproof charts. They're plastic, plain and simple, no coating required.
Not available for everything--but nice when they are.
We also have large plastic "zip lock" map pouches, about 17" x 22" in size, to hold a folded chart or chart book and keep it dry but visible and useable above deck
. You need a grease pencil or crayon to plot on them that way though.<G>