We have no idea what the issue is....
Two (multipart) questions for you, then:
1) Has anyone readily available to this forum ever smelled the indigo abd/or black dye used in this fabric, or have they actually been around for the dye process? If so, could they give a rough description of the dye smells or corroborate whether the smell could indeed be a dye issue? (Wonky long shot, I know.)
This fabric is made of the standard 21oz denim. It is, on its own, the denim IH sell most of. It is then overdyed with black fugitive pigment. The od’ed version is quite a big seller also and has been around for many years. I think that if this was a dye issue it would have come up earlier in the many years of the overdyed denim’s existence, and would be common knowledge in the same way as everyone knows about the faint smell of sulphur-dyed denim.
2) Without giving away any proprietary information, could someone actually describe the overdye process? Like, how do you physically do it? What makes the fugitive pigment fugitive? Do you indeed use some sort of fixative for the indigo? And how do you get the black to stick without then sealing the indigo so that it can't chip?
Question 2 is equally because I'm a curious nerd with an interest in textiles as much as it to help me figure out what to do with my weird stink-pants.
As a curious nerd I encourage you to mine the wealth of information readily available on this forum about the 21oz denim and the overdye process. The short answer is that the 21oz is dyed with indigo and has an extra treatment designed to preserve, but not fix the indigo. The OD’ing uses a black fugitive dye. This is done in a very vigorous, hot, environment that also strips all shrinkage out. Fugitive dye is any dye that does not bond permanently with a fabric and therefore leaves the fabric, or that changes colour when subject to chemical reaction. Indigo is a fugitive dye also.
There is also a lot of stuff about washing jeans on this forum. People have their own routines and ideas about that. The general consensus here is that they are your jeans so it is up to you. In my own experience nothing cleans jeans like a trip through the washing machine. But whatever your approach, once a smell has permeated the fabric and been left there long enough, it can be very hard to get out. Just go into any vintage store and breath deeply.
The only pair of jeans I’ve ever had that smelt like you describe were my first pair of Japanese selvedge from seven or eight years ago. I bought into the whole don’t wash for six months crap. After a while they had a metallic, acidic odour. I followed all the BS advice (airing, freezing, waving over steam
) then I gently, cold soaked, gently warm soaked and then repeated the above with mystical products. By the time four months came around they stank. Only then did I machine wash them. It made a huge difference but the funk never quite left. My point is that unwanted smells, whatever the cause, will only shift with a timely, proper wash.
