Right, so yesterday I told you why your red turns to glop and your yellow won’t dissolve.
Which, of course, left you saying, “Well that’s great, but now what?”
Ah, now what? Now we discuss solutions.
The “easy” thing to do, would be to replace the water. Because water doesn’t get along with our yellow (and to a lesser extent, the red), because magnets like magnets, and our yellow… well it isn’t a magnet.
So, what would be easiest would be to make the solution the dye is dissolved in also be a not-magnet, balanced, hydrophobic (water hating) molecule. Unfortunately, hydrophobic solvents are generally highly caustic and thus not available. Things like… phenol and formaldehyde and benzene (Benzene is just those rings I showed you yesterday).
Ew. Even if your average dyer could get those chemicals, you wouldn’t really want your yarn/fiber soaked in gas, or flesh dissolving goop. Neither would these chemicals play nice with your green and blue dyes, which are hydrophillic magnet molecules.
So, we can’t replace the solvent (what the dye is dissolved in), and we can’t change the dye itself (since then it wouldn’t be yellow anymore). What can we change?
The answer is, anything that doesn’t affect the dyeing chemistry itself. Which means we can add quite a bit of stuff to our dyepot without screwing up the dye.
The most straightforward things to add are things which will interact with both hydrophillic magnet molecules and non-magnet hydrophobic molecules. So, molecules which have a balanced end and an unbalanced end.
These fall into two classes: Detergents and Humectants
Detergents. Detergents are molecules which have a hydrophillic “head” and a hydrophobic “tail.” Your laundry “detergent” is a detergent (in the chemical sense). And the way it works is by forming little groups around your hydrophobic dirt particles, tails (non-magnet ends) pointed in at the dirt, and heads (magnet ends) pointed out at the water. This lets you wash the dirt off with water.
“Soaps” are a specific kind of detergent scientifically called “surfactants” or “surface active detergents” because they have a higher than normal ability to wrap all the way around those little hydrophobic dirt particles, even if that means pulling them off a surface (you, your clothes, etc).
So, you might be able to add some detergent to your dye bath to help the yellow go into solution. The problem is that most commonly available detergents are soaps, which means they are really good at sequestering things (wrapping all around and not letting it touch anything) which can inhibit your dye’s ability to, well… dye. So, go ahead and add a little detergent (the naturally less foamy your detergent the more likely that it will help) but it may or may not solve the problem.
Humectants. These are similar in overall structure to your detergents. They have a hydrophillic and a hydrophobic end, just like detergents. The difference is that their hydrophillic end is REALLY hydrophillic. They don’t just get along with water, they actually hold onto it. The other difference is that your humectants are less able to gang up and “wrap around” hydrophobic molecules, so they won’t stop your dye from interacting with things. Basically, they can make believe that your hydrophobic molecule actually likes water. This is why they’re often called “wetting agents.” (Humectant, from the same root as “humid”)
These are overall a better choice than the detergents, and are fairly readily available. Glycerol and urea are the two most common ones. Urea is generally cheaper, but smells funny and in very large amounts can screw with things. Glycerol is a little gunkier to deal with but doesn’t interact with just about anything (beyond the aforementioned humectant property).
Salts. If you have especially soft water (lacking in calcium and magnesium) then a small addition of salt can help to increase the disorder in your solution, but it’s not likely to help a great deal unless your water is REALLY soft (if you scrub forever in the shower and that detergent never comes off you, same reason).
The short answer:
So, if you’re having trouble with crashing or goopification, try adding a little detergent. If that doesn’t work, try adding urea or glycerol.
Or, use the tried and true method of increasing your free energy and system entropy… put it back on the stove or in the microwave, and heat it up again!
And yes, for those of you wondering, I will post about non-science stuff. Maybe even tomorrow. I might even talk about… knitting! Or you know, that spinning stuff I do!