# discharge issues



## KennyB3000 (Feb 17, 2016)

Been having trouble with this one for DAYS now...

I've been screen printing for 20+ years but am fairly new to using discharge and water based inks. The place I work for has started a push to move to water based ink and discharge printing, and I really really want to get this down. I've been fairly successful with it so far, but this design has thrown me for a loop.

The design is to be printed on 100% cotton red shirts. We've made a screen for the white discharge and burned it on a 155 mesh screen. There is also a black screen (280 mesh) and a green screen (280 mesh) that prints on top of the white. The green and black inks are water based inks, and I burned them on high mesh because there are halftones on each color.

I've printed this multiple times now, and they look pretty good until we do a test wash. The white discharge seems to be washing out, cracking, and fading after a wash. I know some fading is to be expected, but not sure why I'm getting the cracking and washing out. I'm thinking it might be a curing issue.

Here's another thing. I tried printing this with a couple passes of the white discharge, gave it a flash, and printed the other two colors wet on top. Boss said the white wasn't coming out bright enough so we printed some with an extra coat of discharge white after a flash. Could this cause the cracking/peeling? Can you even print/flash/print with discharge ink or is it better to print discharge white and throw a water based or plastisol white on top of that? The feel of these shirts is very important, we need a super soft hand.

So how would you print this? The black is no problem as a straight water based ink, but should we knock out the green underbase from the white screen and use a green discharge?


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## nycmerch (Mar 29, 2009)

We have done a pretty good amount of Discharge but never ran into a problem where our results would crack or fade after washing... except on ribbed shirts... where when stretched you see the black lines. But on standard 100% cotton tees... we never had that issue. Which brand of ink are you using? Is your batch of discharge ink fresh or from previous runs that are being kept in fridge? Which brand of shirt are you printing on?

Normally when we have color to add to a design... we use color discharge. Matsui is the ink we use.


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## KennyB3000 (Feb 17, 2016)

Using fresh mixed Ryonet discharge white. I'll try to upload a pic to show what I'm talking about.


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## jwpintn (Dec 14, 2010)

Excuse my ignorance, but why would you flash? And why would use an underbase? That seems to be the problem, but then again we don't really do discharge. But to my basic understanding of it, the beauty of the process seems to be the fact that you shouldn't need to use an underbase, all colors should be discharge, and run wow. It should eliminate the underbase all togsther, and from what I've read red is not discharge friendly . And forced air and higher curing Temps seem to be favored.


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## Star Silk (Oct 10, 2009)

Hi Ken.

We have been printing Water base/Discharge for a while with mixed results.

There are a lot more variables to deal with when printing discharge or pigmented discharge.

The dye in the shirt could be one issue you have to deal with. We ran a job with white discharge and part of the order looked great however when we ran the large garments we did not get the same brightness in the white. We find different dye lots of the same brand and style of garments can give you drastic changes in the final product.

The water base chemistry also changes with time. The older the inks get the evaporation of water in the ink with give you different results. Try a new batch of water base to see if there is a difference in
the result. Often we had to throw ink out when it aged. If would almost become a cottage cheese consistency.

Lastly your cure times for water base/Discharge printing can require as much as 3-4 time more oven cure time without bringing the temperature above 340 degrees. A gas dryer with lots of forced air
and a long tunnel of heat will give you the best results. The dryer we use has only 12 feet of heat and
this becomes an issue when we have a large logo to cure. We have to set our dryer to a very slow speed to get a proper cure.

You can also try the Rutland Discharge and Pigmented discharge inks. They have worked well for us and there technical support is very good.

Lastly the environment in the screening area should heat temperature and humidity controls. If your work environment is to dry, you will run into a host of other issues.

Thanks,
Brian


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## MrNifty (Mar 29, 2019)

Some colors like Forest, Royal, and any color that is super bright has a much higher resistive dye which causes issues for discharge printing. You probably know that already, but I just wanted to first off mention that. The Ryonet White Discharge won't fully bleach those red shirts, so you kinda have to expect a little transparency. The next thing is one issue that I myself just figured out. The issue is not always with the curing process (although it could be), but because that Ryonet White Discharge is thick, you tend to not fully penetrate the garment with the white. Then even though it is cured, you wash it and the fabric loosens up a bit, and you get those cracks. The two fixes that I have done (depending on the screen mesh needed for the design) is to either use a much lower mesh with the Ryonet White Discharge or make my own discharge white with the discharge base and white pigment (which is far less thick that the straight white). The latter way does not come out as bright as the Ryonet white, but it penetrates much better. Lastly, you can use Rutland's "Penetrant" with your discharge inks, which also helps you really get the ink into the weave of the shirt!


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## samdkelley (Sep 20, 2012)

Could it be that the red shirt has some polyester that would not bleach?


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