Sonora XP Plates on Miller TP104 5color Press

[RobTGuam]

Hello there, we have been using Sonora XP Plates for the almost a year now, but recently we been getting spots on them. We know it is not from our CTP, because we hang a blank (No image) plate and run a test. Our press is a Miller TP104 5 color, our chemistry are as follow, Roller Wash - VARN, Fountain Solution - Nova Fount FS 501 and Achol Sub - Pro Chem AS-R. Any suggestion as to where we can make adjustments or changes to solve this issue? Thank you in advance.

 

[Steve_W]

I had the same problem. Fought it for several jobs and on each job it got worse. I ended up getting our prepress guy to contact Kodak and tell them the problem. The Kodak representative he spoke to told him the plates were expired, judging by the numbers on the package. They were only about 3 months old. Couldn't get the spots off the plate. Kodak said they would get worse as the plates got older too. In our case we don't get enough work for that press to buy a package of 100 plates. We had a similar problem with Trillian plates too.
We use Sonora's too and for the most part they are doing a good job on all our presses. We just have to be careful about handling them before they go on the press. They are very prone to scratches before they are mounted, don't let one plate rub against another without a tissue between them. They don't stand up to a hickey picker either, the hickey picker scratches them. We also found that they should be stored in a cool dark place until the press is ready for them. Being stored in an environment over 80 degrees can cause sensitivity problems when they are developed on the press, very similar to expired plates.
That's what I've learned about them. Didn't care for them to begin with but they are growing on me.
Steve

 

[RobTGuam]

Steve thanks for your sharing your experience on this, actually on this batch of order (30 boxes of 30 plates), we where down to 10 boxes when the spots started showing (13 weeks old). We average about 50 to 60 plates a week. It got worse as we got into the 7th box. We went ahead and contacted our supplier and they where nice enough to give us credit for it. This is the first time we encountered this issue. It could be also that the press room temp goes above 80° in the afternoons in some days when its over 90° outside.