Author Topic: Discharging... powder on surface of cured print  (Read 2809 times)

Offline Du Manchu

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Discharging... powder on surface of cured print
« on: January 24, 2022, 01:11:33 PM »
Hey, we've got a powder on the print area of a cured shirt.  If you rub it, it comes off and contaminates the black image area and the shirt.   This is going to be a big problem with a belt full of shirts.  Can we wash these and fix it, or any other options.

Red Bella 100% cotton shirt. 
White DC print.  Aquarius 100% white DC   (w/ 6% activator w/ 6% distilled water)  156 mesh, 2 strokes
Cured 350 at 2:30 seconds, 8 feet gas

A) Can I fix these?
B) What might we have done wrong with this print run?

Many thanks.




Offline Du Manchu

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Re: Discharging... powder on surface of cured print
« Reply #1 on: January 24, 2022, 07:26:49 PM »
Does anyone have any thoughts on this?  I am stumped and stalled on this job.  Thanks in advance.

Offline zanegun08

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Re: Discharging... powder on surface of cured print
« Reply #2 on: January 24, 2022, 08:33:19 PM »
Post a photo, I'm not sure what "powder on the print area of a cured shirt" means.

If it's flaking off I would say you aren't printing with enough pressure to get the ink into the fibers of the shirt.

I would cure them longer if possible, 3 minutes should be good.  You can also post heat press them to "soften" the feel of the discharge a little bit more, although most of that feel goes away in the wash.

You could try both increasing or decreasing the activator.

From your description I cannot really tell what is going on, however discharge on red is always difficult, I would recommend doing a discharge base and High Solid Acrylic top color, but realistically I would print it with Blocker and two Whites for the best result.

Don't really do white discharge anymore as the inks don't work well in my opinion any longer, as well as Red is probably a B or C on the discharge rating chart.

Offline Du Manchu

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Re: Discharging... powder on surface of cured print
« Reply #3 on: January 24, 2022, 09:58:02 PM »
Thanks Zanegun08.   The bright shirt is unwashed and I rubbed my finger into the black.  This same powder contaminates the other areas of the shirts when folded.   The other shirt has just been washed (and still wet actually) which is clearly not as bright and almost  pinkish bu no longer powdery. 

Offline futurecolors

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Re: Discharging... powder on surface of cured print
« Reply #4 on: January 25, 2022, 10:29:39 AM »
That looks like pigment to me. Possibly laying too much ink down and not curing enough. Like zanegun said, increase pressure and cure time.

Offline zanegun08

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Re: Discharging... powder on surface of cured print
« Reply #5 on: January 25, 2022, 12:53:49 PM »
I can't really answer the question as I haven't seen it, but if your after is after one wash I would be switching inks instantly.

Unless the customer absolutely wants a discharge print and you show them that it looks like that after one wash.  If I were the customer and expecting white print on a red shirt and I washed it one time and that was the result I would instantly be getting a refund or doing a charge back.

I don't offer white discharge anymore as it is no longer a good product, something changed wether it be shirt dyes or the inks or activator, but even testing many products we just don't get the results we used to so discharge base with HSA for a "softer hand", but I really like a bright white print so just do three screens of white.

The white on the black area could be from screen breakdown, I've never seen it look like that before, but could be a small amount of screen breakdown so you are printing a micro amount in that area and then once it goes through the dryer you see more of the effect.  I'd try printing just the white and load it in the dryer in different directions to see if it's air blowing the ink around like that (looks like snow in the wind) or is screen breakdown if in a consistent pattern.

I'd really think hard though if that white after washing is what you want to put your name on though, I wouldn't and I am not even the business owner.


Offline ericheartsu

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Re: Discharging... powder on surface of cured print
« Reply #6 on: January 25, 2022, 03:11:12 PM »
are you over printing the black on White DC?

Also is the White DC being stepped on?
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Offline Du Manchu

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Re: Discharging... powder on surface of cured print
« Reply #7 on: January 25, 2022, 04:45:53 PM »
Maybe?  We've started whittling this down, but have changed too many variables at once, so not there is a bit of confusion.   This is how we originally printed the job that resulted in the powdered cured print:

White on 1,
flash 3, (more than a few seconds)
flash again on 6 (trying to keep pallets warm, but why)
Black on 10

So...we've cracked open a brand new bucket of Aquarious DC White and also mixed it as 80/20 white/base w/ 6% (instead of 100%) and the powder situation seems to resolved itself.   Going to do some wash tests tonight and see.

I am deducing one of the following, but very interested in some opinions:
  a) we over flashed it
  b) old or bad DC white
  c)  100% vs 80/20% issue
  d) stepping on it caused this? 

Appreciate all the help and apologize for the failed experiment with multi changing variables.    I am still very open to suggestions, as we have got to get this repeat job nailed down.   We've wasted a lot of time and money on this SECOND failed print run, and hope to make it up in the residuals....if we can ever get it out the door!

Thanks again.




Offline zanegun08

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Re: Discharging... powder on surface of cured print
« Reply #8 on: January 25, 2022, 09:47:30 PM »
Switch your print order, black first, flash and then print white and no flash before the dryer.

Probably what we were seeing was the squeegee on black was smearing not totally cured white into the black to make that effect.

More print pressure, more cure time, but honestly I don't think white on red discharge would ever pass my standard for white at this point.

We do discharge base under base, and then HSA white on top but even that is iffy to me as it cracks when we stretch it which is partially under curing.  But I typically do 3 screens for a good white, we cannot get away with just two with HSA inks unless the print area is very small.