> On Sep 20, 2018, at 1:17 PM, Paul Roark roark.paul@... [DigitalBlackandWhiteThePrint] <DigitalBlackandWhiteThePrint@yahoogroups.com> wrote:
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> On Thu, Sep 20, 2018 at 2:59 AM daniel andron daniel.andron@gmail.com <mailto:daniel.andron@...>[DigitalBlackandWhiteThePrint] <DigitalBlackandWhiteThePrint@yahoogroups.com <mailto:DigitalBlackandWhiteThePrint@yahoogroups.com>> wrote:
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> Je travaille avec c6 base (réserve en bouteilles 2 litres) pour ensuite Eboni ou Farbenwerk sur une epson 4880-K-LK-LLK. Après 6 mois de stockage j'ai constaté des formations de filaments dans la solution (champignons, moisissure ?). Aussi je rajoute du bicarbonate de sodium (fongicide) environ 10g pour 2 litres.
> POUR LE MOMENT je ne vois plus de filaments et pas de problème d'impression.
> a+
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> I work with c6 base (stock in bottles 2 liters) then Eboni or Farbenwerk on an epson 4880-K-LK-LLK. After 6 months of storage I found filaments formations in the solution (fungi, mold?). Also I add sodium bicarbonate (fungicide) about 10g for 2 liters.
> FOR THE MOMENT I do not see any more filaments and no printing problem
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> The generic base is obviously a "stripped down" version of an ideal commercial base. One major goal was and is to keep it simple for people to get the ingredients and mix. The main issues that I found I was able to avoid, at least where I live, related to the fungicide and also the pH buffering.
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> As to the fungicide issue, it simply turned out to not be needed in my area. I can imagine that both the local type and degree of spores in the air, and the quality of the inputs vary by region. (As I mentioned earlier, one chemist thought the typical grocery store distilled water quality could be trouble in some areas.) Your solution of "sodium bicarbonate (fungicide) about 10g for 2 liters" (hoping the English translation is correct) may be a good one that I should note in a footnote in my In Mixing pdf (http://www.paulroark.com/BW-Info/Ink-Mixing.pdf <http://www.paulroark.com/BW-Info/Ink-Mixing.pdf> ).
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> One variable that I'd be curious about is what version of the generic base you used.. There are 3 in my PDF. The first one, c6a, was the simplest and omitted the Edwal LFN surfactant. I found it worked in old Epson printers with larger nozzles (and probably slower printing speeds). In c6b I added Edwal, and that make a huge difference in the more modern Epson printers I have. Edwal, however, was not as readily available in Europe, though I note that Aamzon and many others may now carry the 3/4 oz. size. That might be easy to ship. I prefer to buy that 4 oz. version, which is rare, but Freestyle seems to have it. (See https://www.freestylephoto.biz/54151032-Edwal-LFN-Wetting-Agent-4-oz <https://www.freestylephoto.biz/54151032-Edwal-LFN-Wetting-Agent-4-oz>.)
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> Also, I'm wondering if the storage temperature could have dropped and caused some of the ingredients to come out of solution/separate and whether agitation of the base at normal room temperature would have caused the ingredients to re-dissolve. It's rather clear from the extent to which stirring in the original mixing is needed to get the base totally clear that the ingredients are close to their limits in this regard. My (well insulated, California) home "darkroom" (now known as my ink mixing room) temperature range is rather limited.
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> Note regarding the various versions of the generic base in my Ink Mixing pdf that in the c6c version of the base I added Tergitol 15-S-7. That is yet another surfactant that seemed to result in slightly smoother prints in the 1.5 pl drop printers. However, Tergitol was never easy obtain. Frankly, I've found that in normal printing, I don't see a difference between c6b and c6b. As such, I now simply use the c6b version for all Epson printers.
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> As to the pH issue, the simple bottom line is that I found the buffers in the inputs I use appeared to keep all the dilutions except the 2% Eboni in the target range. Aside from my old 7500 (now gone), I found the 2% dilution unnecessary. In fact, not only did the pH drift, but it actually was the first and only one to show pigment settlement (in centrifuge testing) outside what I considered an acceptable/normal range. Early in this inkjet era, however, we were obsessed with people being able to see dots, even with a magnifier.
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> The high carbon inks we can mix cheaply combined with a reasonable modern printer (not the 7500, with it's 11 pl (?) drops), should result in very smooth prints if properly set up and profiled. And for those who still put a predominately carbon print under a microscope and complain about seeing dots -- get over it. We've surpassed the old silver print technology in almost all respects. I have found it extremely rare to have a buyer or potential buyer of my prints ask about the technology. And no one off this list or not in the business looks at prints under a loupe.
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> The bottom line is that generic base c6b is the simplest and easiest version to use for most printers in many if not most areas, but the input and possible air impurities, as well as possibly storage temperatures are variables that may affect the suitability of this cheap and simple method of keeping ink costs low as well as allowing users to vary the dilutions of their matte carbon inks. Frankly, using this approach drops the ink cost to the point where it is simply no longer a significant cost to our bottom line of making outstanding, very (the most with the right paper) archival B&W prints reasonable possible by most individual photographers (and some photo schools and a few commercial printers who are price/cost sensitive users of the approach).
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> I'm always eager to hear possible improvements to this open source solution, however. So, thank you Daniel for the tip on the sodium bicarbonate (fungicide) about 10g for 2 liters.
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> Regards,
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> Paul
> www.PaulRoark.com <http://www.paulroark.com/>
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