Digital BW, The Print

"Bob Marsolais" <bob@...> wrote:
>
> Paul, what happens to out of date ink?  If it flocculates, 
> will agitation "unflocculate" it?   

I'm not sure what all happens to the old pigments, but I do see more sedimentation in old bottles that I assume is flocculated pigment.  I doubt you can effectively break up these particles.  From what I can tell the electrostatic repulsion of the particles simply fails with age.

> I've also heard that algae growth may develop.  

Yes, I've heard of this also but never actually seen it.  I've been told stories of CISs in sunny areas getting algae in the tubes.  MIS once recommended keeping CIS systems in the dark as a simple solution.

> To prevent that, I've put a 1 inch piece of copper wire in 
> the storage bottles.

I've speculated that such might work.  The only test I did to some algae polluted water did indicate the growth of the algae was significantly slowed by putting in a copper wire.  I have not tested ink with "copperized" water.  At some point the copper ions might get to the point where the oxidized copper causes some color or other effects on the paper.  It does sound like an interesting approach to test, however.

Paul
www.PaulRoark.com