Discharge ink ->more ink or more heat?

[OhNoPrinting]

so.. gave it another try. Mixed results again.

Look at this photo:



Now the bummer is:

the right one I printed with discharge ink after i mixed the ink and left it for 2 hours to rest. I took it from the pallet directly to the conveyor dryer for 3 runs each 1.20 minute / 160 degree C. Came out super vintagey.

The left one I did a day later with the same ink still in the same screen. Same shirt brand. But this time: i flashed it three time for each 3 seconds and ... voilá: white.

I guess I will contact the seller of the ink and ask for advice on how long the ink should "rest" and if this is a bug or feature :-)

[Rockers]

so.. gave it another try. Mixed results again.

Look at this photo:



Now the bummer is:

the right one I printed with discharge ink after i mixed the ink and left it for 2 hours to rest. I took it from the pallet directly to the conveyor dryer for 3 runs each 1.20 minute / 160 degree C. Came out super vintagey.

The left one I did a day later with the same ink still in the same screen. Same shirt brand. But this time: i flashed it three time for each 3 seconds and ... voilá: white.

I guess I will contact the seller of the ink and ask for advice on how long the ink should "rest" and if this is a bug or feature :-)

What ink are you using?

[OhNoPrinting]

Its (probably) rebranded discharge ink with white pigments mixed into - activator includes Aminoiminomethansulfinsäure but is Formaldehyd-free.

I send an eMail to the supplier to ask what I can check.

[Rockers]

Its (probably) rebranded discharge ink with white pigments mixed into - activator includes Aminoiminomethansulfinsäure but is Formaldehyd-free.

I send an eMail to the supplier to ask what I can check.

My initial thoughts are. Sending it through the dryer 3 times is very different from curing it once at the right speed and temperature. Each time you send it through the ink and the activator need to reach the full temperature first before any further reaction takes place. Magna non-formaldehyde discharge needs to cure for 2.5 - 3 Minutes at 170 degree Celsius. On top of that non formaldehyde discharge whites are generally less bright than classic discharge whites. I assume you don`t have a dryer with good airflow, right?

[OhNoPrinting]

you are totally right that sending the shirts multiple times through the tunnel is less than ideal. but i will do one more test, where i mix the ink, let it sit for 12 hours /print+tunnel/ and then see if i get the left result which is more than ok in terms of brightness. Its just the waiting time of the ink which makes me wonder if i miss something else. (Like with waterbased white: tried to follow the manual, but.. cracking, so clearly my process is not optimized :-)

[tonypep]

Not much help here perhaps but, when working with the (now discontinued) Rutland ZFS systems extensively all day every day, we actually activated the inks immediately before printing. No flashing and down the gas dryer 330 degrees normal retention time with no issues for many years.

[Rockers]

you are totally right that sending the shirts multiple times through the tunnel is less than ideal. but i will do one more test, where i mix the ink, let it sit for 12 hours /print+tunnel/ and then see if i get the left result which is more than ok in terms of brightness. Its just the waiting time of the ink which makes me wonder if i miss something else. (Like with waterbased white: tried to follow the manual, but.. cracking, so clearly my process is not optimized :-)

I can`t really imagine that letting the ink sit for longer will get you a better result. In many cases  the inks won`t discharge very well at all after 8 hours. can I get a link to the product page? Same for the waterbase white.