Green Plates!

[pressdisk]

We have a real head-scratcher going on here regarding dirtied, green plates and quickly exhausted developer.

Our system is a Scitex platesetter, with the imaged plate going through an oven then into a Kodak MKII plate processor, all in line. Our conductivity at incept of new chemistry is 91 or so and can drop to 88 within a day, even without running plates. Sometimes, it will be very stable. Sometimes, we run a lot of plates and sometimes we don't. We use quite a lot of replenisher, regardless - a cube per 20 hours. Kodak has sent their finest people and tried to replenish per plate, anti-ox up, down and in between, replace the sensor (made no difference - the original sensor was okay), replenish on a schedule . . . We are using those consumables like they're going out of style.

What's worse is that it's totally intermittent. Week before last, we ran maybe 30 plates a day and got satisfactory results. On the weekend, we cleaned the processor by hand, using fresh developer, and replaced the developer and filter. We ran a few test plates - the first was fine, the second a little green, the third okay - same content on each plate. The circulation is working fine.

The baking temp and time is correct and consistent. The plates are all from the same lot and are Kodak Gold Thermal.

So, in sum, we get greened plates, bad for 4/c work, obviously and still "pay the price" of exhausted solution. Any thoughts?

Thanks,

Art

 

[margadri]

Re: Green Plates!

I don't know if this can help, but here in Australia we had some Kodak chemistry recalled because faulty!
I wonder if it is going around the globe?

Edited by: Adriano on Jan 29, 2008 5:44 PM

 

[tcollins]

Re: Green Plates!

Hi Art
In the past we used Kodak Gold Thermal plates and had the same issue with the plates having scumming on them (greening as you call it) what we did was change over to Kodak Gold DITP Thermal plates and this issue stopped happening.
We still had the scumming issue laate last year but that was due to a bad batch of Developer

Regards
Tony

 

[Buzz]

Re: Green Plates!

Yeah, that's bad chemistry. I am talking about 980 chemistry. There is regenerator out there with an old yellow label. It's a very plain label with black type. The new labels have a jazzy look to them. They have a bar along the top with some green coloring. Sorry, this is the best I can do since I am not looking at it. But we were going along fine until we grabbed one of the old labelled regenerators and started using it. We started getting very fine lines, similiar to scan lines, running from gripper to tail, then the plates starting showing the green scum. We changed the chemistry, stopped using the old regenerator and now everything is back to normal.