I've had it happen with poly/cotton too - and remember one white tee - my model put it on and then it fell apart. It was a GWAR shirt - and she was super petite and got her to model all the vintage S's - so I think it was 80s.
And both times it came from dry regions - one was stored in a garage where I'm sure it was literally cooked for 20 years. But in that same shipment I had 400 other tees stored the same way that were fine. So I think it starts with the screen printing process.
I just dumped a garbage bag FULL of GNR tees that had that issue. I kept one back so I could do a video of it. Luckily they were all Coma GNR tees that aren't all that popular.
The worst part about that is the dust it kicks up - gets all up in your nostrils. Probably toxic.
But if that's the case, why doesn't it happen with all black NOS tees?
Have you been stuck with a bunch of these lately? Do you see any connection with dry climates?
This question will plague mankind for all eternity.
We're in Tennessee, so it's pretty humid here. Last month, we put 20-30 grams of Silica Gel into each of the plastic storage bins of items we're currently selling to help keep the moisture out, but honestly I don't know if that's a good or bad thing. It's the stuff they put in shoe boxes....so I figured it was done for a reason.
I got some NOS black 100% Cotton New Kids on the Block shirts. We threw them through the dryer first like we always do for anything new we bring in the house, to kill any little buggies. And when we took them out of the dryer, we noticed that there was a fine and sometimes thick coating of black dust in the dryer. This has happened before with unwashed black tees, I can't remember if they were all 100% cotton or not though. But it's possible, although I know that those didn't rip (but we also didn't try to do that). Anyway, as we were pulling them out of the dryer one of the sleeves of one of the shirts literally ripped off. We looked at a couple of other ones and gave them a quick easy tug on the fabric and they all ripped right down the middle like a piece of notebook paper. Very disarming to see in front of your eyes. Like they literally seem like novelty shirts that were made to be easily ripped off a la the Hulkster.
We had about 18 of them left at this point so I decided since they were probably wasted anyway, I might as well try to wash them and see what happens then. After the cycle even more black dust was coating the washer but I didn't notice any particular brittleness to the shirts. I threw them in the dryer knowing full well that this would probably be their swan song. When the dyer finished I started pulling them out, a couple of them were ripped, still others had what looked like moth holes in them where they literally seemed like they just disintegrated. I put them down on a table to inspect them, I just did some test rips on some of them and it was the same deal. But then others didn't rip and while they seemed a little weird to the touch, they seemed to hold up fine. Possibly from another batch that weren't as overcured or something like that?
But yeah so there's about 10 left but they all left behind this odd layer of black dust so I don't know that I feel comfortable selling them necessarily because that's no fun to receive a shirt that is just flaking off black dust everywhere. Although it could be just residual dust from the ones that did rip apart and these ones would be okay? Who knows. In any case I'll probably just hang onto them and maybe try to send them through another wash cycle to see if the black dust issue subsides and if they hold up for another wash. I'm sure they're probably toast though. They're not the most valuable shirts in the world but I know they would move so it's a bummer that they're probably a loss at this point.
Anyway, just thought I'd add my experience into the mix. I doubt there's a solution to this problem, seems like as you guys said, the combo of manufacturing and storage is the culprit across the board. I just know from now on I'll keep a closer eye on any NOS I bring in to make sure I'm not throwing away money again.