Picture Framing on Sheet Fed Presses

[Paultheprinter]

ok, just had a dig and found the info, its in the pia/gatf guide yo troubleshooting for the sheetfed offset press, by thomas m destree page 129. its under tinting which in my opinion is the prerequisit for picture framing, it states avoiding softening the ink, adding a stiffening varnish and reduce ink form to oscillators preassure to avoid emulsification causing an oil in water emulsion. i would add high temperature to the mix as well

Paul

 

[Heidelberg]

I had a client who had picture framing all the time especially bad with Black ink, he changed to a one step fount from Pitman called 'Performa fount one PF CHM 206D'. The picture framing problem has now disappeared.

 

[pthielen]

Picture framing

Picture framing

One reason for picture framing is due to foreign material on the backcylinder.

The second reason may be due to excessive blanket squeeze b/w the blanket and backcylinder from the previous job, leaving a minor indentation on the blankets.

Blanket change may be necessary.

Regards,
Paul
Graphics Technology A.A.S. Dunwoody Industrial Institute
Pressman since 1979

 

[Bkahill]

In most time pictuer framing is caused be the Fountain solution and the ink . If the fountain solution
is high in acid it will break down ink and cause a build up around the sheet and show up on blanket and back cylinder . Check the mixture and see if you can cut back on the solution and the sub as for as you can and still print clean . Hostmann Steinberg makes a one step that i have seen working very well in a few shops. Hope this helps Bob

 

[Bkahill]

Picture Framing is normaly cause by Fountain solution breaking down ink .
If you are running a two step try droping the a little at .

You can test this by taking a small bottle and take your water mix in the tank about one OZ water then put a drop of the ink in. Then shake it up if ink breaks up quickly .Then you have ink and fountain solution problem . Change one are the other.

 

[Peter R]

Pretty basic but check that the form/plate rollers aren't oscillating across the plate. If they are adjustable, turn off the oscillation. If they aren't adjustable & have play in them shim the rollers so there is no play. One of the first things we check before going down they chemistry line.

 

[turbotom1052]

ive encountered this and after trying various measures to cure it with no success finally found a way to minimize it but not completely eliminate it. The reason we didnt stay commited to a cure was because it wasnt affecting the quality of the jobs. Had we be doing long run work i could see it eventually getting bad enough to have a negative effect on quality but all our runs were under 10,00 impressions. It wound up having to do with the grain direction of the plates we were buying. The press was a half sized format and at times we would get plates with the grain going around the cylinder and at other times we would get plates with the grain going across the cylinder. Im not remembering now which of the 2 were the problem grain but id suggest that you just be aware and look for the trend.

 

[nuno100]

Tried pullin half a percent out of fountain solution, down to the minimum recommended level of 2% and reckon it made the framing issue a little worse if anything so will bump it back up to about 2.5% or so.. i reckon its the ink we run, Hostmann Steinberg Impression.. its a very low tack ink and i think it struggles with the ambient temp and steady 13000/hr, even with chilled oscillators etc ad good temp control from the technotrans..

Dear Sir, 3 weeks ago, we changed Impression SF ink from Hostmann Steinberg, but we faced the excessive ink build up ( out side of paper ) on the impression cylinder, we run pH 4.0 ~ 4.2, do you have any idea about how we can solve it.

 

[GazKL440]

We changed to Bottcher S3002 (I think will have to check) fountain solution and it helped significantly. We've since changed to Hostmann Perfexion series ink and it's probably a little worse if anything: it's a hell of a lazy, unresponsive ink however, it takes about 200 sheets to react to duct changes for some reason, which can be irritating when tuning short run jobs...

 

[gordo]

What I find confusing is that the term "picture framing" is not found in any of the books on offset lithography, press operation or ink. At least not the ones in my library including those published by GATF, PIRA, RIT, and Heidelberg. Is there another name for this problem? Has this problem only existed within the past 10 years or so? Or?

best, gordo

 

[Deleted member 16349]

What I find confusing is that the term "picture framing" is not found in any of the books on offset lithography, press operation or ink. At least not the ones in my library including those published by GATF, PIRA, RIT, and Heidelberg. Is there another name for this problem? Has this problem only existed within the past 10 years or so? Or?

best, gordo

The term maybe new but the problem is old.

I noticed it over twenty years ago although I don't remember if there was a specific term used for it. My view is that with the picture framing condition that builds up over a longer run, the ink build up on the blanket is coming from small bits of ink in the free fountain solution film that gets printed to the blanket from the non image area of the plate. It builds up on the blanket because it can't get back to the plate or out on the paper.

I am guessing that this is more of a problem when printing thinner paper since it is more likely to have some contact between the plate and blanket outside the region of the paper. Cutting packing away outside that region has helped on web presses.

It is an interesting problem. I know that some dampening systems can cause ink to be sheared from the ink film and deposited into the free fountain solution films and cause toning which would also tend to increase the picture framing problem. I can also see, as has been said before, that the compatibility of ink and fountain solution chemistries could be an influence too.

Not sure what would be a complete solutions to this problem but it is interesting.

 

[Alois Senefelder]

I Posit

I Posit

Hello fellow Lithographers,

I posit that the problem of Picture Framing began with the introduction of CtP --
so called Chemistry Free plates.

I also posit that these plates are poorly Desensitized The plate manufacturers having -
Passed this Fundamental step in the process onto the Chemistry of Fountain Solutions !

Regards, Alois

 

[gordo]

I posit that the problem of Picture Framing began with the introduction of CtP --
so called Chemistry Free plates.

I don't know if that's the actual cause but I think there's something to what you're saying otherwise there would be some mention of it in the literature. But there's nothing.

best, gordo

 

[Deleted member 16349]

I don't know if that's the actual cause but I think there's something to what you're saying otherwise there would be some mention of it in the literature. But there's nothing.

best, gordo

In our case it was a film based system but it also was with EB inks which might have had some influence on the phenomena.

 

[Lukew]

If all your rollers are shimmed correctly and all mechanical issues are ruled out and you are getting picture framming, garentee it is your fountain solution and or ink that is casuing the issue....

Change your fount to one that does not attack the ink and you will see a massive improvement.

On our machine we had tried many types of ink and founts, but still had picture framing, (especially long run spot colours) Vendors said you can't stop it, it is the machine..Blah Blah Blah

I switched to a fountain solution that is a non solvent base & contains zero alcohol substitutes Ie: specific glycols etc. and begain to run jobs with the same inks that previously picture framed and the problem has 90% disapeard....
I then ran a ink that was designed specificaly to be run with this fount and the problem was completly eradicatd..

Please do some research on what a solvent based fountain solution does to the ink during the run...

 

[nuno100]

What I find confusing is that the term "picture framing" is not found in any of the books on offset lithography, press operation or ink. At least not the ones in my library including those published by GATF, PIRA, RIT, and Heidelberg. Is there another name for this problem? Has this problem only existed within the past 10 years or so? Or?

best, gordo

Dear gordo, yes, it is also very new word for me, I can say it is toning problem, actually I can't see visually on the printed sheet, but very small particle of inks should be in it, because there are large ink piling on the impression cylinder, out side of paper side. I want to know which condition ( chemical point and mechanical point ) can make a this problem, we are using slightly low tack inks ( quiet sound at running, compare to high tack inks ) with high pigmented, pH value is around 4.0 ~ 4.2, and alcohol is around 3 ~ 4%. relatively higher dot gain is around 20% of CMY, 25% of black. From Nuno.

 

[nuno100]

Hi there,

When i first started my job at my new company the picture framing was realy bad, to the point after 10,000 sheets the blankets were glossy with wet ink around the edges of the printed area, this cause ink to build up on the impressions and flick all over the grippers, it was an absoloute mess. We run a 5col SM74 with k&E inks on mainly 70gsm bond, the press runs between 10,13000sph for 15hours a day with no temperising rollers or climate control, ive seen ink temps up to 40 - 45 degres celcius. I tried a few chemistry changes to cure this but found no quick soloution, after a bit of reserch i found out than picture framing is the result of a oil in water emulsion and can be caused by too much preasure with the roller nips, i then dropped all the form to steels and to plate by 1 mm from standard spec and hey presto clean blankets. I have ran this with fount with silly high PH and conductivity levels with damp temps up to 20 degres when the compressor broke and even then i still ran clean and had great lift from the balnkets. the only time it reappears is if i get mega calcium build up and i mean mega, to the point that the rollers a white over 80% of the surface and up to the vibrator roller.

Paul

Dear Sir, you recommended reducing roller nip, you mean fountain roller or ink roller ?

 

[BeauchampT]

We had this alot, but something that helped us out was to put, for lack of a better term, run off strips on our plates when we ran narrower webs. On the plate outside the print area, you put diagonal strips of image that "point" towards the lead edge. Concept is that it draws excess ink in to your image area of your ink train/plate/blanket and minimizes the build up on your edges. I'd say it gave us a 50-75% improvement.

 

[mike carlisle]

1 remedy for "picture framing"

1 remedy for "picture framing"

In our shop we run 2 sheet sizes. We simply cut blanket packing smaller (across & around cylinder) or to just fit. Mark blanket cylinder with the size sheet you run & record size to cut packing. Saves lots of time in comparison to washing impression cylinder. Also a product made by Burnshine part # 3462Q "Chrome Cylinder Cleaner and Desensitizer really works well. Use daily at end of washup for best result. Can be used on "refined" perfecting cylinders to slow down piling/picking.

 

[fireplug55]

Picture Framing and our results

Picture Framing and our results

How much ink are you running when you see this problem?
Is the ink weak?
Is it made with allot of Trans-White or something similar.

I would get my Ink supplier involved.
We are a sheetfed shop and close work with our supplier has given us good results.