Small % dots & inks ability to transfer
This is not a we need help thread.
Perhaps the ink techs could shed some light onto this subject.
An inks ability or not to hold/print a small % dot, why do some cmyk inks print incredibly small dots yet others fail to transfer.
In the last 12 months we have run several ink sets on our machine and noticed a few sets were holding dots of 0.5% or less yet we have had other ink sets go on the press that fail to transfer a dot under 1% - 2%
The ink sets that printed 0.5% or small dots actually became annoying as any background noise in poor quality artwork would show up on the printed material
I understand that to correct the issue of dot gain/loss, the press/ctp would need to be calibrated when each ink set goes on theoretically they should then be holding the same dots
So is it a case of some inks having an excellent level of transfer or a case that some inks have to high a dot gain.
Which ink set would you prefer to be working with
The set that transfers. It gives you a constant known property. Then you have the ability to control the process with your plate curves.
Originally Posted by Green Printer
IMOP this is 100% accurate enabling pressrooms to be a controlled manufacturing process.
Ink Transfer is influenced by -- Press IPH speed, Type of Plate, Type of Blanket and the Substrate.
The transfer quality can come from a variety of different elements, many of which have nothing to do with the inks.
Types of plates used, plate settings, print settings, stock quality, and many more elements all play a factor in the ability for inks to transfer. Find the combination of these factors that give you the desired quality and experiment with inks for best results.
I'm not saying that inks don't play a role in determining the transfer quality, but there are many more factors at work.
Same plates, same blankets, same stock, same fountain solution!
The only difference being the ink.
No ink tech's willing to chime in as to why this happens?
a 1% dot is a tricky beast, you could be running same ink, same fount, same everything and hold it one month and drop it next month, everything may be the same, but water roller adjustment, age of chemistry in processor, glaze on blankets, batch of inks, almost anything could keep you from transferring of 1% dot, don't give manufacturers that much credit that every blanket will run the same and every can of ink will run the same not going to happen
I think the transfer of ink for small dots is quite complicated and is not simple ink splitting.
Originally Posted by TheProcessIStheproduct
I am assuming it is basically the same problem one would have with FM screen printing.
Yes I was unsure, which ink set would have been classed as the best set to start with but it makes sense now.
We have had an ink set on that was holding screens listed on the computer file as
as well as holding open screens listed as
98% on the file.
Taken the ink out and swapped in another ink set and any screen on that job listed under the 2% mark are gone... But in saying that, all the dots are considerably smaller compared to the other ink.
Perhaps this is why some ink sets are approved for 10 micron stochastic and some are not....
I know the original set drove my art guys mad, as they hated the fact the machine would hold anything under 2% as it would mean any poor quality art would show up... but the extra detail in quality jobs looked good.
also, versions of ID and quark will handle those small dots different, we have had trouble with .5% sometimes rounding up and sometimes rounding down, holding 1% dot can sometimes be more of a curse then a badge of honor, if you ever have a real flat tint like 2C, 2M, 2Y, 5k you may get optically something that looks red or blue or yellow depending on who shows up and who drops off...