Old Photo Books and Silica

Alex Nanson (alec@norlex.demon.co.uk)
Sat, 27 Jul 1996 21:07:31 +0100

In message <199607241930.FAA17666@oyster.vast.unsw.edu.au>,
erobkin@uwcmail.uwc.edu writes
>
>First, finely powdered silica is not something you all want to mess with. As
>an inhaled dust it causes a permanent, disabling, potentially fatal lung
>disease. See silicosis in your favorite medical reference.
>
Yes I know, but I wasn't proposing that anyone 'messed' around with it.
I posed the question, because as an ex surface coating chemist it seemed
to me to be the obvious substance to investigate as a means of imparting
'tooth' to a coating as an alternative to starch.

I understand that there are water dispersible silica matting agents
available, for use in water based coatings, but how easy these matting
agents are :-

1) To obtain.
2) To handle.
3) To disperse in gelatine solution, and whether they work.

I have yet to ascertain.

It may well be that the hazards to which you rightfully allude, will
decide me against the use of such matting agents.

I will post my findings in due course, unless that is,my investigation
results in a premature interview with the Grim Reaper!

Alex Nanson
Gloucester UK