Fuji LHPI plates?

[turbotom1052]

About 3 months ago we switched over from an Agfa plate we were running with no problems to a Fuji LHPI plate on our late model Mitsubishi Diamond. Since then we've experienced a myriad of problems we never had before. Some of these problems are persistent and some are intermittent issues. On the persistent front we have experienced significant problems with drying on jobs that do not aqueous coat. I attribute much of these drying issues to the increased demand for water in order to try and keep these plates running clean. I would estimate the increase in water supply to be close to a 20% increase. We tried various amounts of fountain solution and alcohol sub to no avail. Another thing that seems to be consistent is an issue with the non image area "Tinting" on all colors. This tinting of the non image area on longer runs makes for picture framing issues that require more frequent blanket and impression cylinder cleanings.
Another related but intermittent issue would be the issue of plate sensitivity. There are times when the plates (in particular the black plate which we run down first) will get all toned up if we stop the press long enough to do a blanket wash. Once the plate becomes sensitive (usually after running over 10,000 impressions) the plate must be gummed even if the press will be down for long enough to remove a stubborn hickey. It should be noted that the problems with the black plate happens regardless of what unit we print it in, so i think its safe rule out faulty roller settings or mechanical issues.
We were of the impression when we switched over that the changeover would be basically plug and play!!! It has turned out to not be the case and was hoping that some of the members could offer some help.
Below is a list of what products we are using.....
1 Fuji LHPI plates
2 Toyo hyplus ink
3 Prisco 3451 fount
4 Prisco Alkaless 3000
5 Reverse osmosis water supply

It should be noted that we've tried running various amounts of fountain solution and alkaless to a starting conductivity of 1400 up to a starting conductivity of 1900. We've also tried running our chillers at various temps between 65 to 70 farenheit.
Any input would be welcome particularly from people running Mitsubishi presses with this very same plate!!!!
When we spoke with Fuji about these issues they tried to have us believe that we are the only ones with this problem. They also suggested that we switch over to their fountain solution which i believe is Emerald. Seems like everyone wants to sell everything these days. We would love to make this plate work as its a better value but only if were not plagued with the issues we've experienced. Down time to clean blankets and impression cylinders more often is killing us and even though it often takes a loupe to see the slight tinting on the sheet it is annoying to know its there and only a matter of time before a customer notices.

 

[TheProcessIStheproduct]

I literally threw the fuji sales guy out of my shop, he kept bugging me and bugging me about using fuji plates, which I had in the past and they blinded like crazy (and yes when problem happened they convinced us to switch to fuji chemistry) and now he will argue that the blinding never happened, has never happened at any account, and lists all the big players in town using fuji plates. I think they trained to react that way when a problem comes up to make you feel like you are the only one and probably doing something wrong, because it could not possible be the plates...

 

[Prepper]

First question, you had something that was working to start with but switched? Probably cost, I know, but what have the probs cost you?

Second, we went thru similar issues with Ecomaxx, tried everything, couldn't make them work on our 6-color Heidelberg, worked great on our old Harris web though, opposite of what Fuji thought it would be. We went back to a regular process thermal, the LHPJ, and ALL our plate issues went away for 2 years now, but we went thru what you're going thru for about 8 months, way too long in my opinion. I would say test, test, test and only switch if tests go well.

 

[Kaoticor]

Do you have the capabilites to run any Afga plates still? I know you've probably already thought about this, but if you are still set up for Afga, I would make a few sets of plates with them just to be sure.
Bad chemistry can definitely cause the problems you mentioned, but I would go the exact same route you did, focusing in on the plates since that seems to be the most likely cause, and especially since the sales guys always try to just through you new stuff to buy rather than help you troubleshoot the problem.

We used the same ink and fountain solution you do a few months ago, and didn't experience any of those problems. We currently run Kodak plates.

 

[turbotom1052]

Do you have the capabilites to run any Afga plates still? I know you've probably already thought about this, but if you are still set up for Afga, I would make a few sets of plates with them just to be sure.
Bad chemistry can definitely cause the problems you mentioned, but I would go the exact same route you did, focusing in on the plates since that seems to be the most likely cause, and especially since the sales guys always try to just through you new stuff to buy rather than help you troubleshoot the problem.

We used the same ink and fountain solution you do a few months ago, and didn't experience any of those problems. We currently run Kodak plates.

going back and running a few jobs with the agfa plates are not an option for us at this time. What makes this most frustrating is that most of the problems come and go. There are some jobs that we will run ok with the Fuji plates. Notice i said OK and not fine. Even when a job runs ok, significantly more water is needed to keep the job clean. This is the direct opposite of what we were told we could expect with these plates. We were told that the plates will print much sharper (which they do) and that LESS dampening would be needed. Even when things seem clean to the naked eye there is often that "Tinting" in the non image areas. This was never an issue with the Agfas!!!

 

[Joe Duffy]

When I had this issue wit the FUJI plates, I ended up tracking it back to the processor. When the plate was viewed under a 100x scope, I could see part of the coating left in the grain. A rebuild of the processor brushes resolved the issue. I did cut way back on the water when running them, but pressroom chemistry was key. Found out 1 or 2 pressmen had "special" blanket wash bottled and hidden under the press and would use that and suddenly I had a tone issue.

 

[Asures]

It sounds like one or two things may be happening. Being about in the field as the pressroom tech for my company, I come across this every now and then with this particular plate. Not that it is a bad plate by any means but obviously all product changes have their necessary adjustments that must be done in the manufacting scheme of printing.

1st - On the next few jobs, take a Q-Tip and some acetone to the non image area of your plate. Rub out a small area of the non image area and then take a look at the cotton swab. If indeed there is some residual color of the plate emulsion on the Q-tip, then you have what is referred to as "Coating Retention." To the naked eye, under a loupe, or even under a plate reader, you'll never see it. It will manifest itself once you get some friction on the plate and the ink percieves that excess coating on the plate to be image. It will almost look like an extremely fine haze cast into the non image area of the printed material. Probably more visable on coated stock than uncoated as it hides less of this tint.

If you do not see this "Tint" during the inital start up and are able to catch it during the run, stop the press and take deletion pen to the non image area. If needed, gum the area you cleaned before rolling back up to avoid unwanted sensitivity. Run some more sheets and then keep your eye on the cleaned area. If it does indeed clean up, you again have demonstrated that all the emulsion is not entirely being removed from the plate surface.

2nd - The other thing would be "Counter Etching" of the plate. This shows up initially by picture framing on the blankets when running a short sheets and then it transfers back to the plate surface. The plate then starts getting windowing and starts to migrate inwards. Eventually, the entire non-image area will pick up the same tint. This can generally be fixed with an etch that is more active and acidic providing better desensitizing.

Good luck and hope this helps.

Aaron - Gans Ink & Supply Co.
G7 Expert / Pressroom Specialist
(323) 867 - 3677 Direct Cell.

 

[turbotom1052]

asure,
one of the very first things i tried was the deletion pen test and it did in fact clean up the deleted area. Was assured that all was as it should be with our processor (which came new along with the plate contract) by the Fuji guy that installed it. I did not however try the acetone test before the plates were mounted. I will get some acetone and try this today. Hopefully we will be able to arrive at some resolve to this today as we have a Fuji tech coming in for a couple of days. Any ideas on how to open up the operating window of dampening control??? Seems as there is a very thin line between poor color control from too much dampening and toning up from not enough. Also these plates seem to dry up in very different ways that I've ever seen. Most plates will tend start drying up from the gripper. Ive always used the gripper scum line as a way to determine my water feed. These Fujis require us to run so much water that there is usually no visible scum line at the gripper. If we cut down the water to the point of showing a slight scum line then color control seems to suffer. The excess dampening feed appears to me to be nothing more than a bandaid on a gunshot wound. I believe we are running all this extra water to fight an incompatibility problem somewhere else in the process. Im beginning to look at our blanket washers as a possible problem area. The last week or so i have been making it a point to allow the press to run on speed for a minute following a blanket wash in order to better dry the blankets of the solvent. It seems to be better, but because of the come and go nature of these issues, and the dosing changes we have tried within the last week its hard to tell just what is helping.

 

[nhprinter]

This may not be an issue because you've run other plates with no problems, but I was surprised to see how warm you run your chillers. We're running the LHPJ plates (not sure what the difference is) and we run ours around 50 degrees. I know presses vary and the in-house conditions are a factor, but if we tried to run our fountain solution that warm we would have big problems.

Also....we had problems when we first started running these plates. Come to find out they were sending us the wrong developer. I wish I could be more specific, but it's just been too long for me to remember. (I'm old)

Just some thoughts.....

 

[Kaoticor]

Well if you find out more on this problem, please post! We have Fuji plates scheduled for a trial run later on this year, and I would be interested in any possible adjustments I will need to prepare for. Thanks!

 

[Asures]

Turbo,

When you deleted a non image area and it demonstrated that it cleaned up, Fuji should have caught that. That is precisely the issue you have been fighting, "Coating Retention." Unfortunately Fuji didn't and you've been fighting this for some time as the installers maybe be more plate setter oriented instead of being pressroom/print savvy.

Taking acetone to the non image area and applying it with a clean Q-Tip should identify and confirm your issue. If Fuji wants to be combattive / defensive instead of assisting, image the plates in your location and process them in another neighboring shop that they provide contact information or even one that you may have a positive relationship with.

As for the thin line between ink and water on that plate, it's exactly that problem. You flood the plate trying to correct the tint until you compromise color. Then you try and restore order to the print and the tint comes back. In short, you can't get the desired ink / water balance because there is still image in the non-image area.

I would urge you to be cautious with adjusting your fountain solution to wacky doses in attempts to fix this problem. By running the Sub portion of your water higher and cutting back on etch, you may find yourself minimizing one problem but creating a whole other set of issues (ink sets speeds, orange peeling of metering rollers, UV Coating in finishing not adhering, gas ghosting from excess H2o).

If the blanket washers are suspect, wash blankets by hand temporarely to eliminate that variable. The blanket washers will create a tint for 100 - 150 sheets but will eventually go away if over saturation existed. At worst, you'd get a new plate and the tint would go away.

Again, without being in your shop to physically see what is going on, I doubt the blanket washers would cause the tint for the duration of the run when you demonstrated the problem area with a deletion pen.

Good luck to you and please post your findings for all to see.

 

[turbotom1052]

when i refer to chillers I'm talking about the roller chillers not the fountain solution temp. We run the fountain solution temp at app 55 degrees fahrenheit. its the cooling of the roller train that we run at 65 to 70

 

[turbotom1052]

Turbo,

When you deleted a non image area and it demonstrated that it cleaned up, Fuji should have caught that. That is precisely the issue you have been fighting, "Coating Retention." Unfortunately Fuji didn't and you've been fighting this for some time as the installers maybe be more plate setter oriented instead of being pressroom/print savvy.

Taking acetone to the non image area and applying it with a clean Q-Tip should identify and confirm your issue. If Fuji wants to be combattive / defensive instead of assisting, image the plates in your location and process them in another neighboring shop that they provide contact information or even one that you may have a positive relationship with.

As for the thin line between ink and water on that plate, it's exactly that problem. You flood the plate trying to correct the tint until you compromise color. Then you try and restore order to the print and the tint comes back. In short, you can't get the desired ink / water balance because there is still image in the non-image area.

I would urge you to be cautious with adjusting your fountain solution to wacky doses in attempts to fix this problem. By running the Sub portion of your water higher and cutting back on etch, you may find yourself minimizing one problem but creating a whole other set of issues (ink sets speeds, orange peeling of metering rollers, UV Coating in finishing not adhering, gas ghosting from excess H2o).

If the blanket washers are suspect, wash blankets by hand temporarely to eliminate that variable. The blanket washers will create a tint for 100 - 150 sheets but will eventually go away if over saturation existed. At worst, you'd get a new plate and the tint would go away.

Again, without being in your shop to physically see what is going on, I doubt the blanket washers would cause the tint for the duration of the run when you demonstrated the problem area with a deletion pen.

Good luck to you and please post your findings for all to see.

thanks for the help Aaron. The deletion pen test that i did was when we first started with the new plates. The intermittent nature of these problems is what has us so baffled. Ive tried to nail down all the variables and at times its very difficult because of the nature of our work. We run many different stocks with a variety of run lengths. Today i did try a half assed acetone test as per your recommendation. The reason i say half assed is because we had no straight acetone in the shop. What i used was some metering roller cleaner which is acetone based. After some pretty brisk rubbing in the non image area of the plate it came up clean. We proceeded on with the recommended fountain solution change quickly got the new solution to a point where it was performing as good as what we had. Today was not the best day to encounter all the different issues we have come across. The few jobs i did today were all under 4000 impressions. The one issue of the plates getting sensitive seems to only happen when we run in excess of 10,000 impressions. Im hoping that tomorrows runs will allow us to see if we've made any headway on that front. Im pretty confident that we will eventually nail this thing down. The Fuji guys that were in today showed that this was not their first rodeo. And I'm also quite certain that once we arrive at the right balance of all the various consumables the plate will perform fine.

 

[Dan Roll]

Plate companies are fond of the 'acetone test' as it will often indicate the plates are OK when they are not. The result you got using the deletion pen is a clear indication that there was image emulsion remaining in the background, making the plates un-runnable. I prefer to hone the background off and re-silicate the plate using a plate cleaner containing silicate as this will catch conditions making the plate sensitive that the deletion pen will not indicate.
There is not much that can be done to get sensitive plates to print; all of the ingredients in your fountain solution designed to keep the background clean are delivered by and in water, and a sensitive plate's background repels water making contact between the ingredients and the background intermittent at best. If the solution was strong enough to desensitize the sensitive background, it would desensitize the image area, preventing it from taking ink as well.

 

[Alois Senefelder]

PDFs

PDFs

Hello fellow Lithographers,


2 PDFs hopefully of interest


Regards, Alois

 

[John Arneson]

Turbotom,
I have been having the same problems for almost 3 years. I am running LHPJ plates.
I have not been able to solve the problem, but am interested in seeing if you do. Please post any positive results you may come up with.
Thanks John

 

[turbotom1052]

Turbotom,
I have been having the same problems for almost 3 years. I am running LHPJ plates.
I have not been able to solve the problem, but am interested in seeing if you do. Please post any positive results you may come up with.
Thanks John

With the help of a couple of Fuji techs that made a call last week i think we are making some progress. They came armed with an Anchor 1 step fount that seems to be allowing us to print a little cleaner. The issue with the non image area tinting seems to be a little better but I'm still reluctant to say its cured because of the intermittent nature of the problem. One thing we did find is that our doser was not working properly. It seems that the check valve in the doser was not keeping fountain solution at the dosatron and the solution after a bit would drain back down to the drum. When a low water level called for more mix the water feed would run into the tank and it would take a little while before the fount would make its way back up the line and start mixing. A new check valve cured that problem.
A change in my working habits may also have helped with the problem of our plates getting sensitive. It would appear that our blanket washers do not have enough VOC to dry well after a wash cycle. Ive taken to running the press on speed for about a minute after a blanket wash just to help them dry a bit before printing. The Agfa plates we were using i guess weren't as sensitive to the solvent in our blanket washer rolls as the new Fujis.
Ill keep all posted to our progress as it happens.