Digital BW, The Print

Paul,

An interesting note that I found in the past; "distilled water" that 
we think is neutral PH can often be around 6.0 or so. Another note; 
on the oil platform we used tri-ethylene glycol to remove water from 
natural gas. Because our gas had H2S in it, the TEG would become 
acidic (around 4.0), we used TEA to raise the PH on the TEG back to 
7.0.
--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "pr_roark" 
<pr_roark@...> wrote:
>
> Hi Duane,
> 
> 
> > A bit more info regarding this from Epson. The latest patent
> > data(oct/nov 08) show them using both acid and base buffers to
> > maintain pH levels to a declared optimal level between 7 and 
> > 8.5 for very recent inks.
> 
> The HP Grey comes in at 8.83 according to my new but cheap pH meter 
> (calibrated to its 7.01 buffer solution).
> 
> > The acidic buffer can also be a number of things but
> > one mentioned is citric acid, another old photographic standby.
> 
> Yes, that is the obvious one that came to mind for me also.
> 
> > Also mentioned is the reason for the pH range. Apparently the 
print
> > head coatings can be disassociated and jets damaged by levels 
below
> > and above the stated range while all is well within that range.
> 
> That's good to know.
> 
> Thanks for the info.
> 
> (As an amusing aside, I received a "We've missed you, Paul" canned 
e-
> mail from HP to my Verizon e-mail an hour after my post today 
> regarding their grey ink.  The products they had in their database 
> that I'd purchased are many years old, and I've not been on their e-
> mail list for year.  It's good to know they're listening.)
> 
> Paul
> www.PaulRoark.com
>