Digital BW, The Print

Hi -
Haven't been posting here, but often read. This issue struck me:

Going back around 2 or 3 years, there was a problem with Piezo inks 
producing green prints in a most unattractive way.
There were many complaints, and for a while nobody could figure out the 
cause. Eventually,  Jon Cone let us know that after
a time, there was a chemical change in the ink cartridges, or perhaps 
the sponges within (for CIS) and that  the liquid in which the
carbon particles were suspended, reacted with the plastic, producing 
green. The solution was to replace the cartridges, and if memory
serves me correctly, eventually they changed the formulation [of the 
plastic] in the manufacturing process.

There could be something similar going on here!

Also - Carbon pigment is mostly inert  and the inks are in suspension, 
so it's unlikely that the pigment itself has changed color.
Shaking is good, because even small particle suspensions can settle 
out, if left to stand for a while.

Clayton Price


On Oct 30, 2005, at 6:06 AM, 
DigitalBlackandWhiteThePrint@yahoogroups.com wrote:

>
> Jon Dean wrote:
> Subject: Re: Epson Ink Woes
> I've never experienced this ever or even heard of this but the one
> think I could suggest is to shake the carts. I belive as all pigment
> age they can do strange things.
>
> and
> <paul.roark@v...> wrote:
> It's comforting to know it's not just a third party ink problem.