The R500 uses Ultrachrome PIGMENT based inks and has 1.5 picoliter
drop size capability.
This ink is probably unique because to grind pigment particles small enough
to not plug a nozzle that small is no mean task. My GUESS is that with time,
others will either develop the technology to make these inks or will find
means of getting the ink sub-rosa from the original manufacturer.
Until then, you may have to go to Epson for relief.
Bob Williams
My Bad!
I thought you had the Epson R800, which uses Ultrachrome pigment ink.
I never heard of an Epson RX500 and it does not appear on Epson's
website for USA, Canada or U.K.
Are you sure it is a RX500? What country did you purchase it in?
Bob Williams