Re: Eliminating CaCO3 in buffer in "achival" watercolor papers
I've just read somewhere that calcium acetate (the salt of calcium carbonate with acetic acid) is also quite soluble. So, I may try a mild solution of acetic acid instead of HCl too... Regards, Loris. 12 Ağustos 2008, Salı, 1:29 pm tarihinde, Loris Medici yazmış: > Thanks Diana, > > I also thought about citric acid but the product is insoluble Calcium > Citrate (a food additive), thus, it remains in the paper. I'd prefer > something that totally leaves the paper. Calcium citrate may interfere > with the process I intend to use - maybe that's why you didn't get perfect > results... > > Thanks again, > Loris. > > > 12 Ağustos 2008, Salı, 9:16 am tarihinde, dhbloomfield@bellsouth.net > yazmış: >> >> >> Hi Loris, >> >> Not a chemist here, but I also had a horrible time trying to soak >> Fabriano >> in oxalic acid, specifically in preparation for pt/pd printing. Seems >> like I had to be extremely precise with everything; otherwise it was a >> disaster. I could never get it consistently even (the soaking, the >> amount I used, or something). Anyway, something came up about this once >> in >> a conversation with Mike Ware. He said that he thought oxalic acid was >> the wrong way to go, and he believed citric acid would be a much better >> choice-- and gave all the reasons why. That was some time ago, but if I >> can find that email, I'll forward it on. So I did try the citric acid, >> and it worked much better, though I never got an idea of the right >> amount >> to use, how long to soak, etc-- so it was never perfect (though 100 >> times >> better than the oxalic acid soak). I got busy and on to something else >> and never continued with it. or followed up about exact amounts, etc., >> but >> it did work.
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