Ink Build-up on Chrome Dampeners

[Kaoticor]

Press: Komori Lithrone 28
Fountain Solution: Flint Supreme 8168
Ink: Toyo 24/7

Description of Problem: Ink building up on chrome roller in dampening system (not the chrome water pan roller, rather, the chrome oscillator that bridges the form and the metering roller). Unit 4 is very bad, and a slight build-up is noticed on unit 1. Appears to be a ink/fountain solution chemistry, but we have ran both of these products for quite some time without any related problems. Has happened since 2-3 weeks ago. A picture is attached of problem.

Remedies tried:
Thorough flushing and hand cleaning of dampening system
Dampening filters changed
Hand cleaned and gummed (tried both buffing dry and sitting dry)
Used Comet cleaner lightly with gum aplication afterwards
Triple checked all pertinent roller settings
Checked soft roller duromoters and conical tape measurements
Swapped out metering rollers with non-problem units
Tried flushing and remixing fountain solutions at different pH and conductivity levels. (Currently 2800 conductivity at 4.3 pH, 3.8-4.5 recommended by Flint)
Adjusted a wide range of ratio settings (130-180)
Adjusted settings heavier and flooded damening system with solution (Ink build up still took place)
Different styles of washdowns (although we are always very thorough and consistent washing down and have been for years).

Additional notes: Again, we have used both the fountain solution and the ink for quite some time now and have not had any problems even closely related to what we are experiencing now.

I appreciate any and all feedback you might have and for taking the time.

 

[Servicetech]

My best suggestion would be to clean the heck out of the chrome roller.

You mentioned cleaning it lightly with comet, there is no need to be light on elbow grease, comet will not damage the roller. if the roller is contaminated with something stubborn, you'll have to scrub it off. Sometimes on the clean dry chrome roller, you can still see a slight difference in the color of the chrome, this is a contamination that ink will stick to.

Also you might try one of the stronger chrome roller cleaners out there, one of them that contains phosphoric acid. Or in rare cases I have used phosphoric acid by itself to clean the roller thoroughly.

 

[Cornishpastythighs]

Try some industrial cleaner with Phosphoric acid as Servicetech suggested, we have had some success with this for exactly the same issue on our 40" Komori. These are only bandaid measures and do not eliminate the root cause of the issue. I believe this to be an ink issue combined with the Komori dampening system design. As you cannot change the design I would suggest working with your ink company or maybe even trying another manufacturers ink to see if you get some improvement. We have tried every chrome roller cleaner on the market, different types of metering roller rubber and durometers, different inking rollers,different rollers settings, changed roller and fountain solution temperatures all to no avail, we tried another manufacturers ink and got the biggest improvement.
If you own a Komori you are not alone with this problem and although I like our Komori very much it is a very frustrating issue. Good luck

 

[Lennyr]

Ink buildup on dampners

Ink buildup on dampners

Try a 50/50 concentration of white vinegar and water, at wash up.
This works especially good with the problem you get on Komoris.
The acid in the vinegar helps to clean and desensitize chrome and copper rollers

 

[vniehaus]

I worked on a press with quad flow system that this exact problem would happen Isopropyl Alcohol and water would work and clean, clean, clean.

 

[John Arneson]

I agree with Lennyr. Clean the roller with a good chrome roller cleaner and the follow up with a vinegar water rinse with every single wash up.

 

[HPC]

I worked on a press with quad flow system that this exact problem would happen Isopropyl Alcohol and water would work and clean, clean, clean.

Alcohol is a good short term, we have done this too. I suspect someone has changed something to make the ink/fountain solution not agree with one another. Has your water changed?? (stuff out of the tap). We have had trouble with inks as well as fount solutions, running different even though we've been running the same brand. Flip a coin, but change either fount solution or ink, I think you have more than covered, cleanliness/sensitivity issues.

 

[BeauchampT]

If you are running tap water, seriously consider switching to RO, or some other process to soften up your water.

Also, have you checked that there are no deposits on your water form that could be contributing to the problem??

 

[Asures]

Does this problem only happen with certain stocks or is it on coated and uncoated? Any recent changes in your pressroom just happen (new plate supplier, new wash up solvents, new rollers, etc.)?

1. On Komori's, I personally have come across the chrome pan roller being pitted/blistering, and then from lack of an even water film, it transfers ink to the rubber meter and back to the chrome oscillator.

2. I have seen these new processless plates create these issues as well. The non image area is cleaned when dropping damps to the plate - all that debris has to go somewhere. Right into the dampening system!

Try etching the chromes with straight fountain solution. See if it might extend your run length before you toss in the towel.

Good luck!

 

[Kaoticor]

We are getting the problem on both coated and uncoated stocks. We made the switch to the Flint fountain solution about 6 months ago, but this is the first we have noted of any detrimental effects untill just these last few weeks. I checked on the water as well; we have our own water treatment plant here at the printing facility, and they report nothing has changed. I'll try the more agressive cleaning and straight fountain solution etching later on this week, I think we have some easier jobs coming up.

Thank you all for taking the time to provide your feedback!

 

[Alois Senefelder]

Reasons For

Reasons For

Gentlemen and fellow Lithographers,

Ink -- Feedback into Dampening System.

Chemistry of Lithography - Adsorption

There is competition for surfaces in Lithography between fountain solution and ink.

The Fatty Acids in Ink having the stronger molecular bonds are
adsorbed onto the surfaces e.g. Rollers/ Plate Image Areas.

Regards, Alois

 

[Dan Roll]

With all of this emphasis on cleaning I suspect that whatever it is you are cleaning off is being well removed, after all, it is difficult to get anything to stick to a wet chrome roller. It sounds to me like your system is being contaminated while you run with something that is making your chrome roller's surface oil-attractive. If this press hangs a lot of plates over the course of a day I would investigate the plate finisher. This is an often overlooked source of press contamination and can cause just this effect if the finisher contains surface active agents (most do). You can test for this by testing the finisher for foam (mix with water and shake). If your finisher is foamy try washing the plates off with a clean sponge and water before you hang them and see if the problem goes away after a few jobs. If it does, speak to your plate supplier.

 

[Bob Peterson]

I have to agree with Asures. Etching the chromes usually resolves the problem. If using the straight etch doesn't do the trick you will have to use acid. I have attached a PDF that provides a "how to" on the procedure.

You also indicated that your conductivity is 2800. This is too high. No matter what the manufacturer suggests, you want to use the least amount of etch and/ or substitute that allow you to keep the plate clean, any more is just a waste and will cause problems. I have found that a fresh mix should never exceed 2000 mHos and the tanks should be dumped when the solution exceeds 2300 mHos.

Good Luck!

 

[ABC/ALLIED EUROPE]

C.R.D - Chrome Roller Desensitizer

C.R.D - Chrome Roller Desensitizer

I can reccomend to use C.R.D. - Chrome Roller Desensitizer - from ABC ALLIED PRESSROOM PRODUCTS.

It's a product used to desensitize all dampening rollers, chrome as well as rubber. I'ts a combination of micro-filtered gums and desensitizers. It will prevent ink build-up on dampening rollers and improve water receptivity.

Best regards

Konrad
[email protected]

Press: Komori Lithrone 28
Fountain Solution: Flint Supreme 8168
Ink: Toyo 24/7

Description of Problem: Ink building up on chrome roller in dampening system (not the chrome water pan roller, rather, the chrome oscillator that bridges the form and the metering roller). Unit 4 is very bad, and a slight build-up is noticed on unit 1. Appears to be a ink/fountain solution chemistry, but we have ran both of these products for quite some time without any related problems. Has happened since 2-3 weeks ago. A picture is attached of problem.

Remedies tried:
Thorough flushing and hand cleaning of dampening system
Dampening filters changed
Hand cleaned and gummed (tried both buffing dry and sitting dry)
Used Comet cleaner lightly with gum aplication afterwards
Triple checked all pertinent roller settings
Checked soft roller duromoters and conical tape measurements
Swapped out metering rollers with non-problem units
Tried flushing and remixing fountain solutions at different pH and conductivity levels. (Currently 2800 conductivity at 4.3 pH, 3.8-4.5 recommended by Flint)
Adjusted a wide range of ratio settings (130-180)
Adjusted settings heavier and flooded damening system with solution (Ink build up still took place)
Different styles of washdowns (although we are always very thorough and consistent washing down and have been for years).

Additional notes: Again, we have used both the fountain solution and the ink for quite some time now and have not had any problems even closely related to what we are experiencing now.

I appreciate any and all feedback you might have and for taking the time.

 

[nhprinter]

Spamming's bad enough, but bringing back old posts to spam is even worse. Someone get rid of this guy........

 

[ABC/ALLIED EUROPE]

Not spamming, simply answer for a problem. thats all
If someone feel its bad just ignore my post.

Spamming's bad enough, but bringing back old posts to spam is even worse. Someone get rid of this guy........