Ikat (Indonesian "bundle," mengikat "to tie") is a complicated and time-consuming resist-dye technique in which undyed yarns are mounted on a frame in bundles according to the pattern and tied in places with short lengths of banana bast or plastic strips. During the dyeing process, the tied areas resist the absorption of dye and remain uncolored; repeated tryings and dyeings can result in multihued pattern of great intricacy. The preprogrammed designs may be applied to either the warp threads alone (warp ikat), or to the weft (weft ikat) - or to both thread systems at once, so that the patterning of each one supplements the other (double ikat).
Ikats created by dyeing the warp are the easiest to make. Before the warp strings are attached to the loom they are arranged into bundles. Each bundle is tied and dyed separately, so that a pattern will emerge when the loom is set up. This takes a good deal of skill. The tightly bound bundles are sometimes covered with wax or some other material that will keep the dyes from penetrating. The process is repeated several times for additional colors.
Some patterns have many strands in the cloth that are all dyed the same way which creates a blocky design. In some weaving traditions each strand of the cloth may be dyed differently from the ones next to it. Usually the pattern repeats in symmetrical or asymmetrical ways.
After the threads are dyed the loom is set up. The pattern is visible to the weaver when the dyed threads are used as warp. Threads can be adjusted so that they line up correctly with each other. Some ikat styles (like in Japan and Guatemala) don't try to get the patterns precisely lined up, others (like in Timor in Indonesia) the patterns are so accurate, that you have to look closely to determine that the pattern was not printed on the cloth.
Dying the weft makes it much more difficult to make ikats with precise patterns. The weft is one continuous strand that is woven back and forth across the warp, so any errors in how the string is tied and dyed are cumulative. Because of this, weft ikats are usually used when the precision of the pattern is not the main concern. Some patterns become transformed by the weaving process into irregular and erratic designs.
Double ikats are the most difficult to produce. In the finest examples from India and Indonesia, the warp and the weft are precisely tied and dyed so that the patterns interlock and reinforce each other when the fabric is woven. The procedure involves soaking the cotton yarns for dyeing overnight in a solution of candlenut oil, wood ash, and water. After that, they are sun-dried for five to twelve days. Before tying, the warp and weft are stretched on different frames, and the one used for the weft can be adjusted to the desired width of the finished cloth. The warp and weft are constantly compared and measured to ensure the correct alignment of the designs in the finished cloth. The process is very labor-intensive, and sufficient yarn to make several textiles may be tied together to save time.