In article ,
Tim S writes:
Colin Wilson coughed up some electrons that declared:

Hydrofluoric acid which is deadly and should be steered clear of.

I knew there was an acid that did it, but couldn't remember what it
was - it's probably also a biatch to get hold of...

It's very very nasty. Not at all like conc. nitric or sulphuric. Something
about where the fluoride ions go after they hit your skin - and how fast...

Small quantities quickly cause bone destruction.
I think it's only a catalyst, so it's not used up
in the process and can just cary on going.

Hydrofluoric acid used to be used to make frosted
light bulb glass. Glass frosted in this way was very
good at diffusing light without generating much loss.
It was also possible to etch toughened glass (light
bulbs are slightly toughened so they can get away
with using very thin glass).

However, even in such carefully controlled industrial
processes, handling is now considered too dangerous
for this, and they've had to switch to less efficient
(in light terms) methods such as powered coatings.

--
Andrew Gabriel
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