"William Sommerwerck" wrote in message
. ..
There is a conductive residue. A thorough washing with
de-ionized water is usually required.

Actually, de-ionized water isn't de-ionized. It actually has "hard" ions
replaced with "soft" ions.

Uncharged organic molecules, viruses, or bacteria left behind (after
deionization) will not drain the cell-phone battery.