Date   : Tue, 03 Mar 2009 14:03:15 +0100
From   : anders.carlsson@... (Anders Carlsson)
Subject: Cleaning Yellowing Cases

Joel Rowbottom <joel@...> wrote:

> I just happened across this: <http://retr0bright.wikispaces.com/>

It was mentioned on the list a few weeks ago. I have followed the progress 
of this chemistry since last fall, but until now haven't seen anyone do it 
to their Beeb - however lots of other vintage computers.

Merlin at the Vintage Computer Forum speculated it is possible the Acorn 
plastic is of a different compound than other plastics, thus not yellowing 
in the same way. He mentioned antimony trioxide may have been used as a 
flame retardant, which however is a toxic heavy metal later replaced by 
polybromine diphenyl ether (PBDE). On the other hand, if the US 
manufacturers switched over already in the late 1970's, why should Acorn's 
supplier have kept using a toxic formula long into the 1980's?

I assume only practise will tell if the formula works for you as well. Good 
luck.

-- 
Anders Carlsson