Itajime, jammed dyeing, clamp resist dyeing, or woodblock dyeing is a 
mechanical resist that consists of two carefully carved, mirror imaged pieces of wood that are clamped on either side of pleated or folded fabric. Itajime is also called kyokechi. Ita means wood board, and jime means sandwich and tighten. This technique blocks the dye from reaching the cloth resulting in complex patterns.
It is a dyeing technique similar to that used in the Nara period to make kyokechi resist dyed textiles. This involves clamping yarns or lengths of fabric between wooden boards, usually used in groups of 10-20, that have been carved with decorative designs. Holes and channels are made in the wood that allow the dye to penetrate the yarn or fabric.
17th C. Silk, Itajime, provenance uncertain, from Persia or India.
It is said that the sister of Liu Jieshu in the reign of Emperor Xuanzong in the Tang dynasty, 712-756AD, invented the method, which was very popular in the Tang and Song dynasties and was used for tanka covers in the Ming and Qing dynasties.
There are several good examples of kyokechi in the Shōsōin treasure house, Nara, Japan
Itajime block from Japan
Patterned wooden block from Japan. The pattern is made to replicate kanoko shibori.
