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Noritsu 2301 developer stain


Bluemooncamera
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Hi,

We are running a Noritsu 2301 which is producing a dingy, yellowish stain instead of clean whites.  We have tracked the offending chemical down to developer.  At this point we have drained, flushed and remixed both the working tank and replenishing tank, as well as cleaned the racks.  We used fresh chemistry that was not oxidized and recent.  The tank has excellent circulation, so no clogs in any circulation lines.  Yet the developer is still producing a yellowish stained white on paper.  We have plotted with control strips, and they are fairly close to being in tolerance, with the D-Min reading only 2-3 points high.  

My questions are:

We have noticed that there seems to be liquid sloshing around inside the rollers of the racks.  We have broken the racks down, but the rollers seem sealed.  Is this natural?  Is the liquid meant to be there for ballast, or is this likely old chemistry that is slowly leaking and contaminating each batch of fresh developer we mix?  All the racks seem to have some amount of liquid in the roller bars.

Note:  We pinpointed the developer as being the offending chemical by individually hand-dipping already processed white paper into each tank and comparing all the results.  The developer clearly showed a stain.

Any advice would be grand, but it would be particularly appreciated if any other 2301 users can confirm whether the racks for the machine naturally have liquid inside the roller bars.

Thanks

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Don't mind the obvious questions at all, we have been double checking a number of them ourselves.  Yes we are sure.  We are seeing it on both our control strips, fresh paper and processed paper.  We are running two machines (one an old Copal ML300) and using the same control strips and paper in both.  But the Noritsu is staining where the copal is still white.  Also we can take developed paper that is nice and white from the Copal and soak it in the Noritsu's developer and receive the stain.  Bleaching (or even re-bleaching) the stained paper has little to no effect.  So we are wondering if that questionable liquid we can hear in the rack rollers is recontaminating our working tank developer every time we remix, or if there is another area we should look into.

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I will answer one question. The hollow rollers are sealed but they do let chemical inside over time. If you have not had the CD rack in the Bleach position for a few months you "could" get dev contamination from this. If its just old stale CD I dont think this will cause your problem. On the other matter I dont understand why you put already processed paper back in the CD. Is the output OK for a while after changing the CD or always stained?

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Ah, that is good to know that the rollers are supposed to be hollow.  Thanks for informing us of that Magenta.  In terms of the output, it is staining immediately, or at least by the time it takes the chemistry to warm up enough to put paper through it.  We did an interesting test where we started with unprocessed paper and fed it straight into the bleach and through the rest of the chemistry.  It came out perfectly white and great looking.  So we washed the paper well and decided to feed it through the entire chemistry like a control strip and this time it came out with the dingy stain.  Which suggested heavily that the problem was developer, but just to make sure we took individual samples of white, processed paper and hand-dipped them in each tank just to see how all the samples compared, and once again none of the tanks affected the Dmin of the paper except for developer which again produced a dingy, yellowish stain on the paper.

Sort of a separate, but related question.  All the RA-4 chemistry I have worked with before, when contaminated, particularly by bleach, produces a robin's egg blue stain on the paper that gets stronger depending on the degree of contamination.  Is this true of the Fuji FA2 chemistry as well?  I mean, if contaminated by bleach will it also be indicative by a bright blue stain?  Or is this yellowish stain the norm for contaminated CD?

Thanks for the replies everyone.

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FA-2 chemistry is the Fuji version of Kodak SM RA-2 process.

The chemistry is basically the same as RA-4 but a bit more concentrated, so contamination with BF will normally show up as the whites going cyan/blue.

I had to laugh at “The hollow rollers are sealed but they do let chemical inside over time”

If they are sealed why is there chemistry inside them!

But Magenta is correct they are supposed to be sealed and not have chemistry inside them.

I think it is unlikely that the small amount of old chemistry inside the rollers would contaminate the CD, as Magenta has said they would have to be full of BF for that to happen.

Check the condition of the No.2 crossover rollers; these can cause problems especially if they are very swollen. As a test you could swap it with the No.5 crossover, make sure you thoroughly wash the crossovers before and after swapping.

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OK dave have it any way you like they are sealed hollow rollers that are not supposed to leak. But they do, the machine will, or should work with no detrimental effect. You can always replace them if you are that concerned.

As I have said if it just stale old CD I don't see it as a problem. If you have had the Dev rack immersed in Bleach then maybe you had better change the rollers as if it got in it will get out over time.

You are correct that Bleach in the Dev with Kodak will normally be Cyan but I have seen it look like Fogged brown paper, I don't know this Fuji spec so thats as far as I can go

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Thanks for the feedback you guys.  We inspected the CD rollers and they are indeed full at this time.  On another forum's suggestion we drilled small holes in the ends of the rollers, and drained a lot of old developer out of all the rollers.  Our thinking was that maybe being immersed in hot chemistry was causing the rollers to swell slightly and leak at a greater rate than when they were at room temperature and out of the chemistry.  We shall see how this works and do a(nother) thorough cleaning of the tank and pod just for further peace of mind and remix another fresh batch of CD and see if that helps.  

We will keep the crossover suggestion in mind as well, have heard that from another source at this point too.  Can the crossover being contributing to dirty/stained paper?  Or just with paper jams?

Anyway, once again, appreciate all the feedback.  Thank you!

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