The best method of setting the dyes in this direct coloring is that pursued commercially in calico printing, treatment with dry steam, i.e., steam applied at a temperature sufficiently high to prevent its condensation into drops of hot water on the fabric, which would be quite ruinous to the design. This is done successfully by Oriental craftsmen, and it would be very desirable to have suitable apparatus in American schools and studios.
Next best, though considerably less efficient, is the commonly practiced method of laying the fabric between dampened cloths and pressing with a hot iron until dry.
The resist method has an advantage in that it allows the use of a dye-bath. The limitation of temperatures that may be used places some restriction on the choice of dyes. Batik dyeing must be done without melting the wax resist. But after eliminating those dyes which require high temperatures and also those not suitable for pattern dyeing, there still remains a good range of colors. Batik is without doubt the most versatile of all methods of pattern dyeing.
Tie-dyed work depends upon tightly wound string or yarn to resist the dye. It also has the advantage of the dye-bath. Though less versatile than batik, it has a time-honored place as a method of beautiful and charming results. The introduction of sticks over which the tying is done, such sticks as are used by the children in stick printing, has opened new problems with added variety and much interest.
DYES
The colors available for craft work are commonly grouped into the following classes, which will be briefly described:
Direct Colors. These are so called because they are applied to all fibers directly without the use of mordants. They are principally used for dyeing cotton. Some dyes of this class have affinity for both cotton and wool. Most of the package dyes sold at the local stores are of this class. They are applied to cotton in a boiling bath and to wool at high temperature near the boiling point. Different assistants are used varying with the dye and the nature of the fabric.
The direct colors, being very soluble, are prone to “bleed” when the goods are washed, but owing to this same fact it is easy to produce level dyeing on the goods. On this same account, however, and also on account of the high temperature required, they are not well suited for pattern dyeing.
Acid Colors. These have great commercial value for dyeing wool and sometimes silk. The best of them are quite fast to light but not to washing. They are not suitable for cotton or linen.
Basic Colors. These will dye wool and silk directly and also raffia, straw, basketry material, leather and wood. They dye cotton when mordanted with tannic acid, and this constitutes a very large commercial use. Basic dyes are especially strong in coloring power. Many of them are fugitive to light. A few of the best of them, however, when properly applied, are fast to washing and fairly fast to light.