[alt-photo] Re: fumed silica

[Loris Medici]

Thanks much for sharing this Richard,

I would like to ask something: How does silica fume (or fumed silica)
physically act? I mean, does it have a tendency to get airborne
easily? Reading this page, I think we definitely wouldn't want to
inhale silica: http://en.wikipedia.org/wiki/Silicosis.

>From the page:
"...Silica flour is nearly pure SiO2 finely ground. Silica flour has
been used as a polisher or buffer, as well as paint extender,
abrasive, and filler for cosmetics. Silica flour has been associated
with all types of silicosis, including acute silicosis.
Silicosis is due to deposition of fine respirable dust (less than 10
micrometers in diameter) containing crystalline silicon dioxide in the
form of alpha-quartz, cristobalite, or tridymite..."
(In my understanding, silica fume / fumed silica is a more finely
ground / synthesized form of - the above mentioned - silica flour,
right?)

Thanks again & regards,
Loris.


2011/12/16 Richard Sullivan <richsul at earthlink.net>:
> We've gotten some very positive reports on this from the field. At least one
> atelier printer is using it for their platinum work.
>
> It's still in its experimental stage. There are numerous ways it can be used
> so the permutations are virtually endless.
>
> The best way to start may be using it dry. The Athenatype video on Vimeo is
> a good tutorial The first part is dry coating:
>        http://thecarbonworks.com/blog/?cat=38
>
>
> Compiled notes:
>        http://thecarbonworks.com/blog/?p=16
>
>
> Used on Cyanotype:
>        http://thecarbonworks.com/blog/?cat=4
>
> We have done one test that indicates that it makes Pt/Pd work well on
> buffered papers and several reports from the field that confirm this. Howard
> Efner thinks this could be due to the Lewis pH effect.
>
> --Dick Sullivan