Epson explains why thermal printheads fail....

[Ink stained Fingers]

Please read Epson's explanation on page 6f how thermal printheads fail, which indicates why those problems can't be cleaned away in most cases

http://www.multivu.com/players/Engl...ment/ef225a99-a30b-4e52-b6bd-c87d62e47756.pdf

and Epson's printheads are cool and rocket science....... have fun reading this paper, I'm only
missing something by Canon in return about the failure mechanisms of Epson printheads like crystal fatigue of the actuators