Take this with a grain of salt, but if you are willing to venture outside the realm of using things as they were intended I have a bit of a secret to share on finding 99.9998% Isopropyl Alcohol.
BE ADVISED: THIS ONLY APPLIES TO THE RED BOTTLE ISO-HEET
. The yellow bottles are totally different.
I ran across this while working on a different issue and found it to be quite a handy bit of knowledge. This can be used with lanolin to make a lubricant for resizing things made from brass.
The SDS for this
, Section 3, states the ingredients as 99.9998% Isopropyl alcohol and 0.0002% Xylene.
While the Xylene gave me pause at first I did recognize that it is 0.0002% or 2 ppm. Borderline trace amounts. Considering that of the 3 SDS sheets I looked at for standard 70% rubbing alcohol only one even listed water and the others didn't even list the % of alcohol in it, I personally am not that bothered by it considering the amount that you could be exposed to. But that's me.
Educate yourself and use at your own risk.