From: "jimhayes361" <jimhayes@...>
Subject: Re: Chemistry of Windex, Fantastik, 70%Alcohol
--- In DigitalBlackandWhiteThePrint@y..., "erikhuneker"
<erik.huneker@p...> wrote:
Part of
my
> background is in flexo printing (the 50" web, 800 ft/min, 8-colors
> CMYK, $5 million dollar type of machines)
Oh yeah, you mean the web press stuff. Good gosh I at one point
briefly prepared plates for a 6 color web. Huge monsters. Never ran
the darn thing though, yikes. I like keeping all my fingers.
Would the inks be similar then?
as well as chemistry,
> amateur photograph and for 3 mths proud owner of a Canon S800 to
get
> started in digital printing.
Yes, but the Canon uses different technology, not Piezo but some form
of thermal I think- the ink would be way less viscous I imagine.
>
> The inks we use in flexo printing are somewhat similar to the stuff
> used for inkjets (some solvent, water, carrier and pigments etc...).
like Epson or more like Canon or HP tho...maybe they're all
reasonable close when it comes to chemical makeup?
> In my opinion, you certainly do NOT want to use the clear ink. It
> contains the carrier(or base) with the solvents but no pigments,
and
> that carrier will dry and stick to the pad and to the printhead.
Not
> good...
Then the mechanism is if I have a puddle of clear ink base, the
solvent will evaporate out leaving the carrier which will gunk up. If
this is the case, if I now take a drop of MIS pigment ink and put a
puddle down, I'll be left with the carrier and the pigment as gunk.
Wouldn't this happen if a person did too many cleaning cycles and
overwhelmed the vacuum pump hooked under the parking pad?
Just thinking out loud...
>
> Jim, your comments were absolutely correct on acetone, water,
> solvents evaporating etc...
hhmmm..ok. Looong time ago I studied that stuff.<g>
Most solvents that dissolve the
> base/pigment combination (non-polar) do evaporate.
i.e. water-based solvents.
Some that do not
> are oils (as in olive oil, kitchen oils or motor oil). But they do
> not have a good dissolving power, and if a liquid does not
evaporate,
> I am fairly sure that there will be some sticking to the printhead
> and causing trouble printing.
to make it clear to a gearhead...are you saying I want to put on the
little parking pad a water-based solvent that will evaporate
completely, but slowly? Or do I misunderstand?
Since Fantastik is for cleaning kitchen grease, it is then a polar
solvent? This can't be true, as I can spray it on dried ink and it
disloves/dilutes it.
>
> Try to go for the solvents that do evaporate the slowest, and for
> that the glycols are the best option. Careful not to smell them too
> much though, some are toxic...
Well, I was thinking the clear Epson base had di-ethylene glycol in
it. But maybe that's the solvent, and there's also a killer carrier
mixed in.
If I restricted to Windex, Fantastik, or alcohol, I think I would
then
remove alcohol from the list, as I think it evaporates faster than
the
other two mixtures. I think this may leave me with Fantastik as being
the better solvent with a slow evaporation rate.
Perhaps you can suggest a glycol that would be relatively safe to
handle and easy to obtain. Di-ethylene glycol didn't look exactly
harmless, but what do I know?
>
> Hope this helped,
Yes it did, although as you see, it raised more questions. Where I
came from, that was usually a good sign tho<g>.
Jim H.
> Erik.