View Full Version : fumed silica

18-Jan-2015, 19:34
Anyone else pre-coating with it? I tried some I got on ebay or amazon, brushed it on dry and found it made the paper (arches platine) quite repellent:


I suppose buying the stuff B&S sells would be easiest but that takes the mad scientist fun part out of it. If other people are have good results, I may add that to the order next I order with B&S.

Andrew O'Neill
20-Jan-2015, 20:25
I tried… and I tried… and after several sheets of paper and sensitizer, I gave up. Yes, there was a dramatic increase in dmax, but it was hit and miss as far as streaking went. I much prefer acidifying paper in sulfamic acid. Now I have a ton of fumed silica in my darkroom. Maybe I'll make some milkshakes with it...

Jim C.
21-Jan-2015, 11:10
I assume you're pre coating photographic paper with fumed silica ? What's the coating for ?
Just curious because I use it a lot as a thickener for silicones and urethane rubbers and as a matting agent for some paints.

21-Jan-2015, 13:26
It's been used by some to increase blacks for alt process printing (probably by increasing surface area for coating). It's foam brushed onto dry Arches Platine paper in my case.

John Bowen
21-Jan-2015, 14:37
See Richard Boutwell's Blog post, dated March 2012. May shed some light