> The £2 per ream supermarket crap that curls up in hot weather is probably full of acid I wouldn't be so sure. I need paper that is not basic for a hobby of m

> The £2 per ream supermarket crap that curls up in hot weather is probably full of acid I wouldn't be so sure. I need paper that is not basic for a hobby of mine (cyanotype printing, a photographic process that is very sensitive to high pH) and that is actually quite difficult to find these days. Almost all available paper is acid-free, because it doesn't cost much to the manufacturer to add calcium carbonate buffer to the paper. It doesn't mean that cheap paper is good for archival (if only because it likely lacks mechanical strength) but paper made in the last two decades or so is rather unlikely to become yellow and brittle in the future, and it should keep quite long if stored in correct conditions.