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screen printing => Waterbase and Discharge => Topic started by: Stinkhorn Press on February 09, 2016, 11:05:52 AM

Title: can discharge activator powder get ruined/wet?
Post by: Stinkhorn Press on February 09, 2016, 11:05:52 AM
we run a little discharge, maybe 3 jobs a month tops.

We use matsui products (except for activator powder - they all seem to be chemically similar)
USUALLY when mixing ink, we mix our bases and pigments - which is most often slightly looser than a plastisol, but still tight enough to "stick to a stir-stick."

We add 3-5% fixer-n and 3-5% printegen (which makes the ink looser)
We add 6-8% discharge activator (which makes the ink tighten back up - if too tight, add a little water as needed).

TODAY, when the first batch failed, I added the activator before the fixer/printgen - and the ink consistency melted practically away to water??? what gives?
The lid of the activator wasn't put back on tightly last time, can the power absorb water? Enough to do that?


(we're also in ohio, it's been mildly cold, but half the building doesn't have central heat and gets cold on nights a weekends (but not below freezing))
Title: Re: can discharge activator powder get ruined/wet?
Post by: Colin on February 09, 2016, 01:04:20 PM
Activator is always last.

My understanding is that it creates some kind of barrier to the absorption of any other chemicals.  Except water.

Try it again and add your activator last.
Title: Re: can discharge activator powder get ruined/wet?
Post by: Stinkhorn Press on February 09, 2016, 01:35:29 PM
USER ERROR.  :P

I have too many things on my mind. I use the Matsui ink calculator, if you're making a discharge ink, you've got to swap the 301c and 301m bases for discharge base and discharge white. And I totally didn't.

Matsui WB bases don't make discharge inks.
Title: Re: can discharge activator powder get ruined/wet?
Post by: jantexinks on February 09, 2016, 06:26:38 PM
Yes discharge activator can go bad if it exposed to moisture/water.  But usually it has to be pretty old to cause it to fail.
Title: Re: can discharge activator powder get ruined/wet?
Post by: tonypep on February 10, 2016, 09:11:13 AM
By definition ZFS is a crystal, not a powder. Wet=short pot life. Moist=Much longer although it will "clump up"