Re: DIY light source for 10X10" enlarger.

Nicholas:

	Are you sure on the medical ethanol?

	USP means United States Pharmacopeia, taken to mean "of highest purity" 
(after "reagent" and "analytic" grades of chemicals). The only ethanol 
USP I have ever come across is 100% ethanol, prepared from a benzene 
ternary azeotrope made after alcohol distillation to a binary azeotrope 
(95% ethanol in water), then with the last trace of water removed with 
magnesium.  It's not denatured, and at least used to carry a federal tax 
stamp as potable alcohol (although very expensive for the concentration 
of alcohol, much cheaper to buy vodka and drink twice the volume).

	Denatured alcohol isn't generally used for medical purposes because the 
most common denaturants (most common is methanol) are toxic, and many 
are skin-absorbed.

		David

David Kazdan, MD, PhD
Cleveland, Ohio



Nicholas O. Lindan wrote:
> "jjs" <jjs.jjs.net> wrote
>>> ... rubbing alcohol--it contains oil ...
>> It better not contain oil. I use it all the time to wipe plastic before

>> priming it for paint. Ain't no oil in it.
> 
> It depends -- there are two types of 70% 'rubbing alcohol': isopropanol
and
> denatured ethanol.  The denatured ethanol is for medical use and labeled

> USP.
> 
> Then there are 9x% isopropanol and various witch hazel libations.
> 
> I have, on occasion, picked up the wrong stuff.  The USP version has a
> distinct Doctor's office odeur and sometimes a light pink tint.
>