The dyes that I prefer to use in my work are fiber reactive dyes, also known as Procion dyes. And I like to use them because they provide a cheap but more or last longer alternative to the well known Rit dyes. They come in these containers, and in the powder form, and you can find them in a huge array of colors, so you can really choose what you want. They're really versatile, so they work for cotton and for silk. They also can be used cold, which is a really great advantage when you're doing dyeing, because that allows you to just use any plastic container that you have around. And they use very little water, which makes them a really ecological option amongst the dyes. They're also pretty safe, at least as safe as any supermarket dyes, so you can even use them with the kids.
The way that they work is that you'll have to use an alkaline substance, such as baking soda or washing soda, to make them active. And once you mix that activator substance with them, they become active and fixed to the fiber. They follow their name, ‛Fiber Reactive Dyes’.
Even though they're super safe, there's a couple of safety precautions that you should have. For instance, you should always wear gloves to prevent your hands from getting stained, and from getting allergic reactions. Also, if you're really sensitive since they are in the powder form, you might want to use a respirator mask, and even goggles if you're worried about getting your eyes splashed. Besides that, it's always a good idea to cover your tables with a plastic drop cloth or paper, and not use any utensils or containers that you might use for cooking.
But fiber reactive dyes are totally safe to use in your house, with your kids, or in your studio. And this is pretty much how fiber reactive dyes work.