Digital BW, The Print

Robert

Your posts are always very informative, thanks. You've spoken in the past
about OBs and now buffering agents, do you have any think to share with us
about the effect of the paper's inkjet receptive coating on permanence? It
would be particularly helpful to be able to ascertain which papers would be
most suitable for dye inks, which for pigments, and which for hybrid blends.

Todd Flashner

> Excellent post, Martin!
> the only thing i would add is that the "amount" of buffering agents
> tend to affect the archivalness of a paper.  Libary of Congress
> standards indicate that they consider an archival paper to have not
> more than 3-5% of fillers (fillers include buffering agents like
> CaCO3, pigments like titanium dioxide or silica) by weight. (my
> memory may be off here, but i think i posted the LoC website in an
> earlier post and Martin bookmarked it in the Files section of this
> list.
> Fillers are measured by the amount of ash resulting by burning the
> paper. 
> Museo contains 2.8-3.3% filler or buffering agent (Calcium carbonate
> in Museo's case; this is the most common alkaline buffering agent--
> arches, etc have used this for centuries.)  We have tested some
> papers--internally--with an ash content as high as 10%.
> hope this helps,
> robert rex
> crane & co