[TrueNorthGear]

I'm in the process of researching adding screen printing to the heat applied decoration that I'm already doing. I would like to go water based, but I'm also interested in discharge. I've read that curing discharge with anything other than a conveyer dryer is not a good idea, but I've also seen videos of people using heat guns and heat presses to cure.

For anyone that has done discharge with these methods, has it been successful and any issues with the smell and fumes? I love the printing process, but don't want to smoke out the family either. I don't foresee large print runs in the near future, so it might only be a few dozen at a time.

Thanks!

 

[NoXid]

The fumes are quite pungent! Sulfur and acid and fermented roadkill. Lots of ventilation required. You might also consider an organics respirator, as some formaldehyde might be released, as well as zinc.

My shop is in a garage, so I open the door when using discharge. I also have a vent hood over the heat press I use for curing. A heat press works fine for this, and probably any waterbased ink other than puff.

A heat gun also works, and as you saw in the other thread, is what I first used. You'll probably scorch a few shirts before getting the hang of it.

Although fabric dyes vary by garment maker, there are some colors that typically do not discharge well. And sometimes they over-dye a batch of shirts to black that were originally some other color that they decided they have too much of. Over-dyed garments cannot be discharged.

 

[TrueNorthGear]

Thanks for the great advice. The plan for the water based ink is to use a heat gun to flash/dry to the touch before curing with the heat press.

My heat press workstation is in the space that was roughed in for the bathroom so it does have a bathroom fan, but it runs through the HRV mixing with fresh air coming into the house, rather than a direct exhaust like your dryer would have. It'll be okay for curing the water based, but might not be best for discharge,

I think I'll get my feet wet with the water based first, then I'll see about trying discharge. The rep from the local screen printing supply company I'm talking to doesn't recommend doing discharge in a house. Once I get there, I could try curing the discharge in the garage depending on the weather. I believe the discharge they sell is formaldehyde free.

Thanks again for taking the time to respond.

 

[NoXid]

Formaldehyde is generated as part of the chemical reaction when the discharge is activated by heat. It is the simplest of all aldehydes and is essentially unavoidable as a side effect of such reactions. Any chemical reaction that can strip dye from fabric is at least somewhat hazardous.

That said, you want ventilation when curing any ink. WB ink has more than water in it. Even the shirts themselves have sizing and dye bath residue that comes off when you heat them. Not as obviously noxious as discharge, but still a bit unpleasant--and in any case your nose is not the final word as to how hazardous something is Sounds like your house is one of the modern air-tight type. I wouldn't cure anything inside one of those.

 

[into the T]

Not as obviously noxious as discharge, but still a bit unpleasant--and in any case your nose is not the final word as to how hazardous something is Sounds like your house is one of the modern air-tight type. I wouldn't cure anything inside one of those.

bang-on NoXid, discharge is horrifying to anything dead and/or living

many truly noxious vapors are not odorous (natural gas has methyl mercaptans added so you smell rotten eggs, H2S in decent concentrations will kill you before you notice a smell, carbon monixide also has no odor)

there is a reason they brought budgies into the caverns, and it wasn't for their cheerful songs, it was for when they died you ran as fast as you could out of the mine

maybe TrueNorth should get a budgie....

 

[TABOB]

The fumes are quite pungent! Sulfur and acid and fermented roadkill.

Not a bad description... but I think you mean "decomposing roadkill" because salami (fermented meat) tastes nice in my pizza.
Anyway, here is why discharge is far from ideal for home printers.

The nasty smell comes from the combination of hydrogen sulfide (rotten egg smell), ammonia, and sulfur dioxide.
You don't want to breath these.

 

[NoXid]

Not a bad description... but I think you mean "decomposing roadkill" because salami (fermented meat) tastes nice in my pizza.
Anyway, here is why discharge is far from ideal for home printers.
View attachment 276013
The nasty smell comes from the combination of hydrogen sulfide (rotten egg smell), ammonia, and sulfur dioxide.
You don't want to breath these.

I'm partial to roadk--err, fermented critter on my pizza too 🍕

 

[TrueNorthGear]

Thanks for more great input. I'll stay away from discharge until I can be better setup for it.

Makes me wonder about stuff like Jacquard deColourant (used to be called Discharge Paste). Its instructions are geared to using a home iron to introduce heat and start the chemical reaction. They say it's safer to use than bleach.

 

[TABOB]

They say it's safer to use than bleach.

It depends on how you use the bleach.
Cold bleach is relatively safe.
Apply heat to accelerate the effect and you'll be filling your house with chlorine gas, which is very toxic.

Jacquard deColourant is a solution of sodium formaldehyde sulfoxylate.
Apply heat and it will also release toxic fumes (formaldehyde, sulfur dioxide, etc).
It is less effective than thiourea dioxide, so you will have to use 5-6 times more of it.
What you end up is pretty much the same amount of toxic fumes.

Its instructions are geared to using a home iron to introduce heat and start the chemical reaction.

A home iron will do it, but you will still need ventilation.

 

[TrueNorthGear]

Thanks Bob. I wasn't suggesting it was any less toxic. I find it interesting that they market it to the home crafter that may not be aware of the level of toxins involved in the process.