Ph level for water based inks on paper

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ewt123
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Joined: Mon Aug 30, 2010 6:14 pm

Ph level for water based inks on paper

Post by ewt123 »

I have a question about the ph level of a water based inks on paper, is there a ph level that would be too high ? Currently running on a Manzoni press ,no pumps very little movement of ink in the pans . It is inline with a bag machine . We have been running our ph high 9 to 10 levels to keep everything open ,is this too high ? Ph adjuster is 1 to 2 % DMEA . Sometimes we are seeing pigment settling to the bottom of the pans after a long run ,4 to 5 days 24/7 . Any guidance or experience would be appreciated. Thanks
Frank Burgos
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Re: Ph level for water based inks on paper

Post by Frank Burgos »

I do not think it's too high, but I would try to keep the range narrower. That may mean more frequent, but smaller, adjustment's

I keep for 9.1 to 9.8, with the target being 9.5. I learned this through speaking with multiple ink manufacturing reps over the years.

I have heard some reps say, "our inks are pH stable" and "you don't have to check the pH with our ink". I have never used one of these types of inks, though.

Pigment settling is normal and expected, if you're keeping it in the pans for 4 or 5 days. This is strange. I'll have to look up the Manzoni press to see why it's too inconvenient to replenish the pans more frequently. Under most circumstances, 4-5 days is way too long to leave a pan in a press without swapping it for a fresh one or cleaning the one that's in there.
Richprints
Posts: 12
Joined: Tue May 09, 2023 11:10 am

Re: Ph level for water based inks on paper

Post by Richprints »

the amines will evaporate off even with pH stable inks. I also believe that your range is ok. you definitely need a way to agitate the inks if you are running them in a pan that long.
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