I have a pair of trousers which are 97% cotton and 3% elastane, they are currently white but I want to dye them black. I bought a Dylong machine dye, but have only ever dyed things 100% cotton in the past and am not sure if the dye will take to these trousers. Anybody have the answer to my dilema!?

Cotton is the best thing to dye so you've got no worries there! The only thing you need is lots of salt! And follow the instructions! You need to wash it first, then dye it, then wash it again to get rid of the excess dye, then run the washing machine again but empty. Make sure you have lots of time to do it! The only shortcuts you can take is to not wash the fabric beforehand. And perhaps not doing the final wash with the empty machine. But I warned everyone so they wouldn't put a load of whites in the machine after I'd used black!

Yeah it's fine. I only think there's a problem with the percentage of cotton is smaller than the percentage of other fabrics.

Yes that material is totally fine but be aware that to fix the colour you'll need to put it on quite a high heat and the trousers may shrink a bit as a result.

Actually that goes for all dyes except cold-water dye, but I wouldn't recommend using cold-water dye for black as it takes several hours compared to other dyes and if you take the fabric out too early it goes green...

Just thought I'd add that in lol

It’s worth noting that black is one of the more difficult colours to obtain, since it has to be so dark. It could turn out that you’ll need to dye the trousers twice, since the first time it may not come out strongly enough. That’s not necessarily got anything to do with the fabric type though, your trousers will take the dye fine, it’s only black that can be a nuisance.

As Georgi said, the process for machine dye is very extensive, although it’s certainly a convenient method and ensures the dye is nice and even. I’d suggest if you find you want to dye them a second time, that you choose one of the hand dyes to makes things quicker. This is more a personal preference, but when it’s only a smallish garment, the hand dyes aren’t a problem, are quicker and save you a lot of the time, water and electricity the machine dyes require!

Oops I stand corrected just found out that Dylon have changed their machine dye so you can use it at 40 degrees now, so no shrinkage. Sorry about that >_<;