[R-390] How are your knobs ?

[Charles Steinmetz]

Robert wrote:

>A word on acetone: it polymerizes and leaves an organic residue.

Do you have references in the scientific literature that discuss this 
polymer residue phenomenon?  My quick search didn't turn anything 
up.  Acetone is rated as 100% volatile and is certified for 
residue-free cleaning to a number of aerospace and military standards.

I have never observed a residue on optics cleaned with acetone, 
although there have been reports that it can dissolve rosin (used 
through the mid-20th century as an inter-element cement) and deposit 
it on the outer surfaces of a cemented-element lens.  Also, some 
commercially available acetone has trace impurities that can remain 
after evaporation, which has been reported by amateur astronomers in 
connection with cleaning telescope mirrors.

Best regards,

Charles