If you're ever succesful in this endevour, you could sell the process/formula and make that in royalties without lifting a finger - now that's a retirement! ;-)
I read one of pisquee's comments and they so often sound completely negative. Then I realise he and a couple of others are playing devil's advocate and that makes me look seriously at it all again.
Exactly! Basically, if you say something, where I think you've got it wrong, then I am going to want to correct you - not to make you out to be a fool, but to try and educate you (and anyone in the future that is reading this thread.) Especially with regards to things like ICC profiles, where you have no experience or knowledge, and I think due to this you may have a better understand of your whole process, even if you can't/won't use ICCs, if you at least know and understand the concepts behind colour management and ICC profiles.
I have seen a lot of posts in the past on this forum and others, from people proclaiming they had found the holy grail formula to achieve cotton sublimation, including posting photos of their work/products. In the end though they all disappeared and went quiet. There are some products on the market claiming to do what you're saying, we even tried one, and it washed out in the first wash. We then called the supplier to ask about why this happened, who said they'd call us back, and never did.
What seems different with you is your perseverance, you aren't giving up, and your posting results of your work as you go. You may get there, or you may always be chasing after the impossible, but no one could say you haven't tried, and I do admire that - so many people just stick to printing on what their supplier can sell them, without ever experimenting on anything, which seems sad, for a process which although grounded in physics and chemistry, but appears to be magic in the results achievable. Why lose the excitement of printing your first mug, and not try and discover other exciting things no one else has yet?
We can only ever sublimate to a polymer based product - whether this makes up the whole product or a thin layer which has been applied is the difference. Polyester fabrics and polymer based plastics are what can be actually sublimated, along with various polymer based coatings (including liquids and power coatings)We are never fully Sublimating anything, as far as I can tell we are only ever sublimating a 'Coating'
The orange sunset shirt that pops up in my posts, has been washed over 100 times now, and after the first wash there was no feel of anything in the shirt. But I cannot remember exactly what I used.
Obviously, I don't know what your supply chain is like, or where you are sourcing your shirts from, or even how you store your stock. But, is there a remote possibility that the shirt in question isn't actually 100% cotton, and is either 100% polyester or a poly/cotton mix. Ignore any labelling on the shirt, as these can easily be wrong, either by factory mistake or lies. Only you can tell, but from an outsider's perspective, it would seem to be a possibility that need ruling out, as a mistake like that would explain why 1 of the shirts is seeming to be fully sublimated and wash proof, whilst whatever else you do to try and recreate it is failing.