Especially if you are new, you may be wondering exactly what goes into the process of making a tie-dye shirt. You probably have read all kinds of different instructions and it is unclear to you what tools you need to use. Luckily we have a few years of experience as tie-dye artists and we have the answers for you.
The short answer is that we do not normally use vinegar in the tie-dye process. In fact, when we are trying to tie-dye a shirt we actually use something called soda ash which is alkaline. Vinegar is acidic which is the contrary of what we need. For the dye to work with cotton we need to create a basic (alkaline) environment and vinegar would ruin that. If you are planning on tie-dyeing a regular shirt, I would suggest staying away from vinegar.
The more complicated answer is that there is a use for acidic products like vinegars, but it is a very specialized use. The only time where you would want to use acidic products is if you are trying to dye wool or other protein fibers. Even then, vinegar isn’t the preferred option because it has disadvantages over other chemicals.
What if you want to dye wool?
If you are trying to dye protein fibers like wool then you should use a slightly different process than normal tie-dyeing. Fibers made from animal proteins are quite than, let’s say, cotton. For protein fibers you need to introduce an acidic product to enable the reaction between the dye and the proteins.
If you want to dye wool you probably are thinking about using vinegar to activate the dye. If you are familiar with vinegar you will know that it smell quite strongly and it can be unpleasant. For this reason and others, we prefer using citric acid whenever when want to reduce the pH of a solution. For dyeing wool you need to lower the pH quite a bit and you would need a lot of vinegar, which isn’t ideal. Vinegar is a weak acid and we prefer using citric acid which is stronger and doesn’t smell.
Citric acid is a safe chemical that comes from citrus plants, it has the benefit of being odorless and is more potent than vinegar so you need to use less of it to make the water acidic. Tie-dye artists do not commonly have a use for acidic chemicals. The only real uses are for dyeing wool and to experiment with the dye reaction. If this is the case, we recommend using citric acid, but keep in mind that it isn’t standard in kits. Luckily it is really cheap to buy in large quantity if need be.
How can acid affect the tie-dye process?
You can experiment with stopping or altering the reaction between fiber-reactive dyes and plant fibers. Natural plant-based fibers need an alkaline (basic) environment in order to react with dyes. This is accomplished by introducing soda ash, a basic chemical product.
In theory there could be a use for a lightly acidic bath during the
rinsing process. You could fill up a container of water with a slightly
acidic solution into which you will submerge the shirt to quickly stop
the dye from reacting. We normally use only plain water for this step,
as we find that it works flawlessly even without changing the pH of the
The idea is that the dye will stay reactive only as long as the pH is sufficiently basic and you can use an acid like citric acid to quickly neutralize the solution. The neutralization of the solution would quickly stop the dye from reacting further and would stop the dyeing process.
As part of the normal tie-dye process, we actually submerge the shirt in a cold water bath to accomplish something very similar. Moving the shirt to a large volume of water already dilutes the soda ash quite a bit and will pretty much neutralize the solution. Using an acid bath could, in theory, be better than using plain water, but this subject remains to be tested and explored further, as we do not have the answers.