Digital BW, The Print

"Yan" <ylucille@...> wrote:
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> I have been wondering about the causes too. ...

What I have occasionally seen is dark lines in the Eb6-Y nozzle check. When this happens, it does affect the printing. Either a cleaning cycle of printing a purge pattern of mostly yellow seems to clear it.

I'm not sure what the cause is. My hypothesis is that Eboni K gets sucked up into the yellow nozzles through some type of capillary action. Note that the Y and LC positions are right next to the Eboni MK position in the 1400.

I've never had a persistent or even regular occurrence of this. So, I've pretty much put it in the very occasional nuisance category. It may be that under some circumstances that don't occur in my situation make it happen more. I'm not sure what the factors are.

I've never seen the effect in Eb6-LC or LM.

I usually run what I'm now labeling "Eb4+" in my 1400. (See a draft PDF at http://www.paulroark.com/BW-Info/Eboni-4-Plus.pdf) So the LC position is, for example, HP LK (30% HP PK). It could be UT14 LC or Noritsu-Epson advanced dye, depending on what I'm doing. I've never detected the issue with these inks either.

I'd guess that frequency of use of the printer is one factor, but I'm not sure.

> It is either the consistency of carbon concentration ...

It could be right at the nozzle if the ink was left for a long time. Again, I've been more suspicious of capillary action pulling the MK ink up from the pad into the adjacent positions -- Y in my case.

>... the epson printer being 'aware' that the cartridges are not genuine and slightly sabotaging the ink firing.

I doubt it. It would be more regular. I have one older printer that flashes a warning at me all the time, but I've never seen actual sabotage.

Paul
www.PaulRoark.com