Image area get stain

saravinfo10

Member
Why image area get stain like this in web offset
 

Attachments

  • photo7897.jpg
    photo7897.jpg
    326.3 KB · Views: 265
Yes it's offset sheet electronic file not available. In sheet why the image area get stain. If desensitizing agent not applied on
will image and non image area get stain. But here image area only get stain Why?
 
We are applying gum to protect the non image area and to give hydrophilic property to the non image area then why image area which has photosensitive coating get stain. Image area must get ink only not stain.
 
are you referring to the stain surrounding the black type? If so I would suggest a brisk circular motion cleaning of the plate AFTER youve removed the ink with a solvent. One you've thoroughly cleaned the black plate with a creme style plate cleaner suitable for your brand of plates I would apply a generous coating of AGE and then be sure to buff out the AGE completely leaving no traces of the AGE.
 
My question is while making plates we are applying gum to the plate then send to the press room. If we did not apply gum in the plate making stain will gum in the press run. But you see in the pic black type and yellow screen are got stain those are image area. If gum not applied in plate making non image area only will get stain. But in this plate image area like black and yellow screean re got stain because not applying of gum in plate making. My question is we are applying gum to the plate to protect the non image area. why image also got stai
 
saravinfo10,


Question: Are these "Stains" visible on the plate - BEFORE the plate image areas are inked - in, via the Press. ?


1) Whose Plates are you using? 2) Are you using a Plate Exposure Control Strip?




Regards, Alois
 
saravinfo10,



Let us be CLEAR - the stains appear on the paper and plate after inking - up?


Answer questions - 1) and 2) please.


3) Have you checked the Chemistry and Conductivity of the Plate Developer/Gum or Finisher?


Regards, Alois
 
Yes the stain appear on the plate and paper after inking up.
1.we are using topaz ps plate
2. Not used the control strip
3.chemistry and conductivity of developer,finisher or checked
they are ok
 
saravinfo10,


SO every plate on every unit of the press - HAS these "Stains/Oxidation Marks" somewhere randomly?


Regards, Alois
 

PressWise

A 30-day Fix for Managed Chaos

As any print professional knows, printing can be managed chaos. Software that solves multiple problems and provides measurable and monetizable value has a direct impact on the bottom-line.

“We reduced order entry costs by about 40%.” Significant savings in a shop that turns about 500 jobs a month.


Learn how…….

   
Back
Top