They were right behind me, but I got tired of looking and had lunch! =P
haahaaaaaha
I only had a tiny amount of 99% isopropyl so I did all tests with 70% and Denatured (clean burning with mystery ingredients)
To minimize evaporation and decrease possible enhanced hygroscopic proterties they were left to sit undisturbed partially submerged in the chemicals, with equal volumes of air.
I used a few black keycaps from three different sets for 4 different time periods.
-5min and less normal cleaning exposure
-1hr exposure soak
-6hr exposure soak
-12hr exposure soak
here are my odd and interesting findings... =)
1)keycaps with legends and coating from my stock Filco board-
Isopropyl
-5min, no change/effect
-1hr, slight chalky residue with whitening/clouding on "some" keys and mostly to the tops. The effect is semipermanent.
-6hr, chalky residue on "most" keys which can be wiped off but "most" left a semipermanent slighty cloudy whitening to the key.
-12hr, heavier chalky residue on "most" but otherwise the same as the 6hr test
Denatured
-5min, no change/effect
-1hr, no change/effect
-6hr, slightly chalky residue that can be wiped off, slight clouding/whitening left over that can "mostly" be wiped off too!
-12hr, very chalky residue that can be wiped off but the slight clouding of the plasic is most semi-permanent this time.
2)Filco coated legends replacement set-
Isopropyl
-5min, no change/effect
-1hr, some had a slight chalky residue or whitening, but I was essentially able to wipe/rub it all off
-6hr, some had a chalky residue but some had a whitening/cloudy effect that is mostly permanent, some with very tiny blisters.
-12hr, medium to heavy chalky residue which can be wiped off but leaves a mostly permanent cloudy/whitening on the key.
Denatured
No change/effect at any soak duration
3) Blank Filco keys uncoated-
IsopropylNo change/effect at any soak duration
Denatured
No change/effect at any soak duration
Special notes:
1) no embrittlement noted for any of the keys
2) The formula for the coatings has changed a number of times
3) the keys are not made of a "lesser" plastic.
4) you are good if you just clean them normally, no extended soaking (as with some keys)
5) higher percentage of Isopropyl can damage the coating quicker.
I hope this was of some interest or help
(I have some other info but I need to get back to work)
thanks for reading =)