Block printing is a special form of printing first developed in China. The earliest known example with an actual date is a copy of the Diamond Sutra from 868 A.D (currently in the British Museum), though the practice of block printing is probably about two thousand years old.
The first step in block printing is the production of the original document. This is laid on a large, smooth wooden block and fixed into place, reversed. Next, craftsmen of various skill levels, ranging from master carvers for the fine work to less talented artisans for cheaper blocks or less important sections, carve the original painted, drawn or written image into the block of wood. The block can now be covered with ink and used in a press to create duplicates of the original.
In some ways block printing is superior to cast type or moveable type -- for a language such as Chinese which has a very broad character set, block prints are much cheaper to produce for the initial run. The process also allows greater artistic freedom, such as the easy inclusion of pictures and diagrams. However, printing blocks are not very durable, and deteriorate very rapidly with use, requiring constant replacement that limits the possibility of large-scale print runs. Printing blocks can, however, be made from a variety of materials such as wood, linoleum, rubber, or even potatoes.
Dhamadka a village in Gujarat has many printers using mostly madder root for printing red color, rusty iron solution for black color and indigo for blue color. These fabrics are known as Ajrakh. The designs made by block printing are geometric. Many states have block-printing workshops using chemical dyes. However there are only small pockets of areas still using natural dyeing with age-old recipes and local plant material.
In Rajasthan, hand-woven cotton is printed with dye and then over printed with a mud compound used as a resist. When the mud dries the entire fabric is dyed in an Indigo bath. The areas covered with mud retain the red design while blue penetrates the remainder. The two designs on sale at this stall were called "young womans cloth" and "old womans cloth."
Masuliputnam in Andhra Pradesh is the main centre of block printing where the fabric is known as Kalamkari. The cloth used generally is mill made cotton, which is first bleached with cow dung and placed in the sun. The next step is to soak the cloth in a mixture of Myrobalan and milk. The Myrobalan contains tannic acid and acts as a mordant helping the dyestuffs to bond with the fibre. The buffalo milk, having high fat content, helps prevent the dye from running. Then the black outline is printed using a solution made with rusty iron soaked in sugar water and bran for several weeks. When the solution comes in contact with the myrobalan it turns black. The next step is printing on another mordant, alum.
This bonds the red dye, Madder Root, after boiling, to the areas that receive the alum. These steps continue until all colours have been printed or brushed on. It is crucial to have a good water supply for washing after printing. It takes weeks to complete all these steps.