Digital BW, The Print

Ernst,

>> The base:  4 parts distilled water and 3 parts glycerol.  
>>(I used Kic technical grade.)

>What is the risk of technical grade glycerols bringing 
>fungi/bacteria in the ink mix?

I don't know.  I used it because for small volumes it was cheaper.  See
http://kicchemicals.com/995tech.htm for the description of their "technical
grade" glycerin.  They also have very high grade versions.

>A friend had that kind of trouble with MIS 7600 inks in two 
>9600's at some point and we solved it by filtering with 9000 
>damper sieves and adding some drops of fungicide.  I don't know 
>whether that base was glycerol but it is likely to be similar.


That is disappointing to hear.  I think most of these inks include some
agent to suppress fungus, etc.  I'm assuming that the amount of original
Epson ink in the mix will still have enough to do the job in most
circumstances.  After all, they must design the inks for the worst possible
storage and use situations.  

I made a batch with some isopropyl alcohol, which, among other things, is
supposed to help.  I found no differences in printing, except I didn't like
or want the smell.  If fungus is a problem, that might be one way to deal
with it, however.

I'm curious about the filtering.  The IB-FS mix is going to need better
high-shear mixing and filtering before it'll be acceptable for large format
printing.  (The desk-top printer carts are easy.  It's the large,
un-agitated carts where the problems are showing up.)  I'm hoping to try to
design ways of doing this that will open the total pigment market to
darkroom hackers like me (and artists who want to design their own color
palettes).  The commercially-available products I've found so far are not in
that category, in my view.  So, affordable 1 or 0.5 micron filters that
don't soak up lots of (costly in low volume batches) ink are on the list of
things to find.  The damper filters and MIS's large format CFS filters could
be possible solutions to this issue.  As a practical matter, I might just
recommend that every large format printer use a CFS for filtering and
agitation reasons.

Any thoughts on these issues are most welcomed.

Paul
www.PaulRoark.com