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Not sure about Sporklenz but yes IPA70 is referring to an Isopropyl Alcohol solution of 70% isopropyl alcohol. Higher concentrations are also effective but abo

Not sure about Sporklenz but yes IPA70 is referring to an Isopropyl Alcohol solution of 70% isopropyl alcohol. Higher concentrations are also effective but above 75% you risk burn or excessive drying upon direct skin contact. FWIW, a 99% concentration will very quickly pick up atmospheric moisture and stabilize closer to 96% in all but the most dry of environments.

Scoundreller 7y ago
> Not sure about Sporklenz but yes IPA70 is referring to an Isopropyl Alcohol solution of 70% isopropyl alcohol. Higher concentrations are also effective but above 75% you risk burn or excessive drying upon direct skin contact. FWIW, a 99% concentration will very quickly pick up atmospheric moisture and stabilize closer to 96% in all but the most dry of environments. During a previous outbreak that led to hand sanitizer getting hard to find/expensive, I just dumped a bunch of 70% rubbing alcohol into my existing bottle once it gets half empty.
dTal 7y ago
50-70% IPA is actually a more effective disinfectant than 99%; the water helps it penetrate cell walls, I'm told.
- inferiorhuman 7y ago
  The water slows down the evaporation letting it linger long enough to be useful (at least that's what I think I read). Either way, 70% is gentler on skin. 90%+ is great for cleaning oily stains and whatnot.
kens 7y ago
The chemistry is kind of interesting. If you distill isopropyl alcohol, you can't get more concentrated than 91% because it forms an azeotrope. That is, if you try to distill 91% isopropyl alcohol, the vapors are also 91% concentration, so distillation doesn't get you any further. Thus, 91% isopropyl alcohol is a common product. Similarly, ethanol forms an azeotrope at 95% concentration, so you can't distill higher than that. This is why, for instance, Everclear has a 95% alcohol concentration. (You can produce higher concentrations, of course, but it requires a more expensive process than distillation.) https://en.wikipedia.org/wiki/Azeotrope https://en.wikipedia.org/wiki/Azeotrope

Scoundreller 7y ago

> Not sure about Sporklenz but yes IPA70 is referring to an Isopropyl Alcohol solution of 70% isopropyl alcohol. Higher concentrations are also effective but above 75% you risk burn or excessive drying upon direct skin contact. FWIW, a 99% concentration will very quickly pick up atmospheric moisture and stabilize closer to 96% in all but the most dry of environments. During a previous outbreak that led to hand sanitizer getting hard to find/expensive, I just dumped a bunch of 70% rubbing alcohol into my existing bottle once it gets half empty.

dTal 7y ago

50-70% IPA is actually a more effective disinfectant than 99%; the water helps it penetrate cell walls, I'm told.

inferiorhuman 7y ago
The water slows down the evaporation letting it linger long enough to be useful (at least that's what I think I read). Either way, 70% is gentler on skin. 90%+ is great for cleaning oily stains and whatnot.

kens 7y ago

The chemistry is kind of interesting. If you distill isopropyl alcohol, you can't get more concentrated than 91% because it forms an azeotrope. That is, if you try to distill 91% isopropyl alcohol, the vapors are also 91% concentration, so distillation doesn't get you any further. Thus, 91% isopropyl alcohol is a common product. Similarly, ethanol forms an azeotrope at 95% concentration, so you can't distill higher than that. This is why, for instance, Everclear has a 95% alcohol concentration. (You can produce higher concentrations, of course, but it requires a more expensive process than distillation.) https://en.wikipedia.org/wiki/Azeotrope https://en.wikipedia.org/wiki/Azeotrope