magenta

[kupluk]

i always have this kind of problem...
whenever i print magenta color....
prosentage of dumpening unit always high over 88%, sommetime over 95%
dumpening unit setting as heidelberg standart setting...
dumpening solution 3% alcohol 12%...
ink setting from PPI, but i mush lowered arruond 50% until 65% in all ink zone...
meanwhile the dumpening at the other printing unit (cyan, yellow, black) lowered than 60%
water conductivity 1800 - 2300....

can you help me to solve this problem???

SM 74-4
2010

 

[D Ink Man]

Ask your ink supplier to incorporate 3% of blown castor oil to your magenta. It should change the emulsion properties and run more akin to the K-C-Y.

D

 

[DeltaE]

It might be from combination between ink and dampening solution (good with C, Y, K but not good with M).
Changing ink brand or dampening solution like alibryan would be good way to firgure out. If it doesnot work, please check your rollers adjustment or swap colors M and another one.

Good luck!

 

[aqazi81]

It looks to me like your conductivity is too high. You are using 12% IPA which is high in my opinion, and with that high dosage conductivity should not be that high.
Are you using TAP water or RO? What is the conductivity of your water if you are using Tap water.
What is the starting conductivity and pH of your fountain water when you mix it fresh?
How often do you change your fountain water?

 

[Amymartines1]

Hey

Hey

I think you should ask your Ink maker to add some castor oil. I think that'll work for you.