Bleach is a handy way to mark fabrics, and it turns out that combining bleach with a 3D-printed design is an awfully quick-working and effective way to stamp a design onto a shirt.
While conceptually simple, the details make the difference. Spraying bleach onto the stamp surface helps get even coverage, and having the stamp facing “up” and lowering the shirt onto the stamp helps prevent bleach from running where it shouldn’t. Prompt application of hot air with a heat gun (followed by neutralizing or flushing any remaining bleach by rinsing in plenty of cold water) helps keep the edges of the design clean and sharp.
We wondered if combining techniques with some of the tips on how to 3D print ink stamps would yield even better results. For instance, we notice the PLA stamp (used to make the design in the images here) produces sharp lines with a slightly “eroded” look overall. This is very much like the result of inking with a stamp printed in PLA. With a stamp printed in flex filament, inking gives much more even results, and we suspect the same might be true for bleach.
Of course, don’t forget that it’s possible to 3D print directly onto fabric if you want your designs to be a little more controlled (and possibly in multiple colors). Or, try silkscreening. Who knew there were so many options for putting designs onto shirts? If you try it out and learn anything, let us know by sending in a tip!
Cool idea!
FWIW, a solution of white vinegar and water neutralizes bleach much faster than water alone. I have never tried it on fabric so by all means test on scrap first. For that matter, just about any mildly acidic solution – citric acid, for example – will neutralize chlorine bleach.
Do you want to create chlorine gas?
Mixing bleach with acid doesn’t sound safe tbh
To be clear, we’re talking about both a small amount of bleach – just enough to show the image without running or bleeding – and a very weak acid. Both the rate of chlorine gas production, and the total amount produced, pose no danger at all. It’s not nearly the same as, say, dumping a cup of vinegar into a vat of bleach.
Don’t do this!!!! Mixing sodium hypochlorite with any acid like vinegar or HCL will produce Chlorine gas. Chlorine gas can be fatal if inhaled.
I have firsthand experience with chlorine gas produced in this manner.
It’s not dangerous. Chlorine isn’t a poison, it’s a strong irritant. The amount you make using this method will be very low, good ventilation will resolve all your problems.
I actually made enough of the stuff that I had to leave the room hacking and coughing… and yet, it didn’t kill me.
It’s totally fine to work with, just use proper ventilation.
I have always heard mixing amonia and bleach is stupid dangerous, but acid (no matter how dillute and weak) apparently has the same effect so lets not tempt fate.
On a side note I wouldn’t do this anyway, bleaching to the point where you are taking something dyed a dark color all the way back to white is bound to eat up the fabric, and I doubt the item would last over time
With a specifically constructed stencil and/or strategic stencil placement, eating away most of the fabric might yield results that some would want to replicate intentionally. Possibly acid would be more effective for this application.
I’ve mixed bleach and ammonia. It’s stupid. Don’t do it.
I mix a fairly strong sodium hypochlorite and hydrochloric acid all the time. I mean, yeah it is diluted in like 15000+ gallons of water, but I do it. Sometimes I even jump into the vessel with it a bit later. :)