Ink pilling on Impression cylinder

pacificiam

Well-known member
Dear All,

Its serious issue we are facing on uncoated paper, that ink is gets accumulated on impression cylinder while printing other side.

We did lot of R&D on ink. We tried different ink on uncoated substrate. But result is not satisfactory.

Ink accumulated on impression cylinder after every 3k-4k sheets. It create problem likes hickey/ picking/pilling on previously printed area. It also results in production loss.

Following action we took to avoid or minimize it.
  • Changed the ink
  • Used rough side 1st for printing.
  • Used smooth side 1st for printing.
  • Kept sheets for more that 48hrs for drying.
  • Print on another side as soon as completion for 1st side. Time is less than 2hrs.

Please suggest any other method to avoid this or any chemical to apply on cylinder to minimize this problem.

Also suggest property of ink that need to be check.

PS : Paper pH is 5.5
 
There used to be a wax that you could apply to the Impression cylinder that helped keep the ink from sticking to the cylinder. You could try turtle wax also. This only a suggestion. Sometimes old school remedies still work.
 
I did a Google search on Impression cylinder wax and found a company called Nikken that sells pressroom products and they list a product that addresses your problem. Turtle wax is is a wax that is used in the after market for putting a shine on the paint finish of cars. Hope this helps. The Nikken web site is www.nikken-chemical.co
You can check for more hints on Google.
 
Problem

Problem

Hello pacificiam,


A PDF - Ink Build-up on Impression Cylinders.



Regards, Alois
 

Attachments

  • Problem On Imp Cyl. v 2.pdf
    23.8 KB · Views: 371
Dear Alois,

We are running machine with minimum fountain.
pH of fountain is 4.8-5.1
We are using IPA
We have 4 colour press and we are running 4+4
We are using Indian WFU
Moisture contain of paper is 4-5%
 
Dear All,

Its serious issue we are facing on uncoated paper, that ink is gets accumulated on impression cylinder while printing other side.

We did lot of R&D on ink. We tried different ink on uncoated substrate. But result is not satisfactory.

Ink accumulated on impression cylinder after every 3k-4k sheets. It create problem likes hickey/ picking/pilling on previously printed area. It also results in production loss.

Following action we took to avoid or minimize it.
  • Changed the ink
  • Used rough side 1st for printing.
  • Used smooth side 1st for printing.
  • Kept sheets for more that 48hrs for drying.
  • Print on another side as soon as completion for 1st side. Time is less than 2hrs.

Please suggest any other method to avoid this or any chemical to apply on cylinder to minimize this problem.

Also suggest property of ink that need to be check.

PS : Paper pH is 5.5

So if I understand you correct, you are printing one Coated one side paper, and when you run the sheets through on a second pass, you get bad set-off on to the impression cylinders inside of the image area?. If this is the case, we have experienced that same problem here. Two things we found that helped for that problem in our shop:

Use an aqueous coating if your press supports it. Increase the coating feed for the uncoated paper and make sure your dryer is able to keep up with the moisture outflow.
The extra drying time helps (although usually not practical)
 
So if I understand you correct, you are printing one Coated one side paper, and when you run the sheets through on a second pass, you get bad set-off on to the impression cylinders inside of the image area?. If this is the case, we have experienced that same problem here. Two things we found that helped for that problem in our shop:

Use an aqueous coating if your press supports it. Increase the coating feed for the uncoated paper and make sure your dryer is able to keep up with the moisture outflow.
The extra drying time helps (although usually not practical)

Dear sir,

We dont have aqueous coating sir.
We increased our drying time but result is not satisfactory.

Can anyone tell me which property of paper need to be check and what will be its min. and max value.
 
Help

Help

Hello Pacificiam,

Clarification of the problem?

1) Do you have assisted drying at the delivery end of Press e.g. I.R.?

2) If not, by extended drying you mean longer time interval between printing 1 side and back-up?

3) Are you using conventional Oxidation type litho inks?

4) Are you using Foreign/Indian manufactured Inks?

5) Are the Plate/Blanket/Impression-Paper NIP pressures correct?

Finally, in my opinion the problem lies with poor Ink/Paper relationship, e.g. Ink Absorbency


Regards, Alois

2 PDFs that you hopefully will find interesting
 

Attachments

  • Paper Ink Variables # 1220.pdf
    684.7 KB · Views: 295
  • Ink Receptivity # 1221.pdf
    590.7 KB · Views: 263
Last edited:
Hello Pacificiam,

Clarification of the problem?

1) Do you have assisted drying at the delivery end of Press e.g. I.R.?

2) If not, by extended drying you mean longer time interval between printing 1 side and back-up?

3) Are you using conventional Oxidation type litho inks?

4) Are you using Foreign/Indian manufactured Inks?

5) Are the Plate/Blanket/Impression-Paper NIP pressures correct?

Finally, in my opinion the problem lies with poor Ink/Paper relationship, e.g. Ink Absorbency


Regards, Alois

2 PDFs that you hopefully will find interesting

Dear Sir,

Thank you for your data.
1) Our press is enable with IR dryer
3) Yes!! Our conventional inks is oxidation type
4) We are using Indian inks.
5) All nip pressure is correct. We are facing this problem on our all multicolour m/c
 
ABC Allied Ink Repellent

ABC Allied Ink Repellent

ABC Allied Ink Repellent does the job, please see attached.
 

Attachments

  • 95-30057 Ink Repellent.pdf
    723.9 KB · Views: 299
First thing that will solve your problem is better ink. If that's not available a simple wipe of your impression cylinders with a good liquid silicone such as Prisco Slide will help quite a bit. You should also consider getting rid of the IPA at your next roller change.
 
Last edited:
Orientation!

Orientation!

Hello Al,


mmm I wonder which Orientation, anyway a PDF for your perusal.


Regards, Alois
 

Attachments

  • Which Orientation.pdf
    22.2 KB · Views: 277
An old school solution was to clean the cylinder well or even polish it then rub it down with fountain concentrate (not solution). Repelex was always the best.I'm not sure if that is still sold.
 
You need to go to a high solids, low petroleum solvent type of ink formula. AS a general rule of thumb for the press person, the ink should NOT STAY OPEN any longer than "8" hours in bulk.

Usually quite an easy fix via the ink medium. D
 

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