If you are like most stitchers you probably don’t think much about how your threads get dyed. And we shouldn’t really, it’s kind of like knowing how a car engine works — nice but not essential for the task at hand.
But you will find some terms used over and over. Today I’m going to clear up some of the confusion by defining and explaining some terms.
In order to dye you will need: thread, water, dye, mordant, and fixative. Changes in each of these will affect the end result.
Threads (or fabric) to dye comes in two forms: Neutral goods (also called ready-to-dye or RTD) and already dyed goods. Already dyed goods are the kind of threads we normally use. RTD goods are the natural color of the fiber source.
Water is usually just the water from the tap. Because the mineral content of water differs from place to place, this may affect the chemicals in the dye.
Mordants are put into water and thread is soaked in them before dyeing. While the primary purpose of a mordant is to help the dye penetrate the thread, differert mordants can also affect the final color, sometimes significantly.
While there are many types of dye, they break down into two classes: natural and chemical. Natural dyes come from plants, minerals, and animals. These have almost entirely been replaced by chemical dyes which were invented in the Mid-nineteenth Century. All dyes work by causing the color to penetrate the fibers of the thread or fabric. There are different dyes for different kinds of fibers because different fibers take up dye to different degrees.
After the thread is dyed the dye needs to be made permanent. This is done by using a fixative. Depending on your dye the fixative can be as simple as ironing it (heat is a common fixative). Another common fixative is vinegar.
Once the thread is dyed and the dye is fixed, it is rinsed to remove excess dye.
That is the basic process that creates all colored thread. If the process is done in small batches, using mostly non-mechanical means, we call the thread hand-dyed. Often, but not always hand-dyed threads show some variation in shade or, less often, color.
Overdyed threads take already dyed thread and dye another color over it. If you use a blue dye on RTD thread, the result is blue. If you overdye blue on gray thread, the result is a muted blue. If you dyed the same blue on a yellow thread, the result will be green.
Space-dying is the technical term for painting threads with dye. The thread is stretched out and woulnd around pegs or poles. It can be wet or dry (each gives a different effect). Dyes are painted onto the thread in a specific order. However, the space between colors, the length of color and just about anything else can differ throughout one dyelot (one batch of one thread dyed at one time).
Many of the threads we call “overdyes” are hand-dyed or space-dyed.
Ombre is yet another dyeing technique that is used but that you won’t see on tags. Ombre threads are put into the dyebath (dye + water) then gradually pulled out of the bath so that there is a gradation of color throughout. Do remember though that while a thread could be dyed in this fashion, it might be skeined to look as if it was not. This is because the circumference of the skein is different from the circumference of the threads as they were dyed.
Although you may not see much of this information on your thread tag, knowing the terms for dyeing will make you better able to identify and use different threads.