Sunday, January 13, 2013

Printing Methods; Methods of textile printing

Methods of Printing 
There are three basic approaches to printing a color on a fabric. Direct, Discharge and Resist. Transfer Printing is comparatively a new method which is also gaining popularity Direct Printing. The most common approach for applying a color pattern is direct printing. It may be done on a white fabric or over a previously dyed fabric, in which case it is called overprinting. The dye is imprinted on the fabric in paste form, and any desired pattern may be produced. The dyes are usually dissolved in a limited amount of water to which a thickening agent has been added to give the necessary viscosity to the print paste. 

Direct Printing Method

The principle of direct printing is creation of a colored design by applying a dye or pigment directly onto a textile substrate (yarn or fabric). Discharge Printing. Another approach for applying a color pattern is discharge printing. The fabric is dyed in the piece and then printed with a chemical that will destroy the color in designed areas. Sometimes the base color is removed and another color printed in its place, but usually a white area is desirable to brighten the overall design. When properly done, discharge printing gives very good results; however, the discharged areas may literally fall out of the fabric if the goods are not thoroughly washed after printing (a rare situation today). The usual method of producing discharge prints is to print the design, such as polka dots, with a paste containing a reducing agent. A steaming follows and then there is a good washing to remove the by-products of the reaction. Resist Printing A third approach to obtaining a color pattern is resist printing. Bleached goods are printed with a resist paste––a resinous substance that cannot be penetrated when the fabric is subsequently immersed in a dye. The dye will affect only the parts that are not covered by the resist paste. After the fabric has passed through a subsequent dyeing process, the resist paste is removed, leaving a pattern on a dark ground. Their are several other methods also for printing textiles. Two are of significant commercial importance: the screen print method and the roller print method. A third method, heattransfer printing is a comparatively new concept & less significant. Other printing methods rarely used in commercial production of textiles are block, batik, ikat, and resist printing. Many textile printers print fabrics in both screen and roller methods. Most heat-transfer printing is done by printers that specialize in this method. 


Batik cloth is made by a wax-resist process. The name batik originates in the Indonesian Archipelago, where resist printing has become an important art form. Wax is applied to the areas that the printer does not want to dye. In Indonesia a small, spouted cup with a handle called a tjanting is used to apply the wax. Melted wax is poured from the tjanting onto the cloth. When it hardens, the wax coats the fabric so that the dye cannot reach the fibers. 

If several colors are to be used, the process becomes somewhat more complex. For example, if a fabric is to be colored white, red, and blue, the artisan begins with a creamywhite cotton cloth. Those areas that are to remain white and those that are to be red are coated with wax. The fabric is now subjected to a blue dyebath, and the exposed areas take on the blue tint. The wax is boiled off and reapplied to cover the blue and white areas. When the fabric is placed in the red dyebath, the color penetrates only the uncovered areas of the design. After dyeing is complete, the fabric is treated with a fixative (a mordant) to make the colors fast, and a final rinse in hot water removes all traces of wax. For faster production a technique was devised whereby the wax could be printed onto the surface of the fabric with a device called a tjap. The design is carved on a tjap block, the block is 


No comments:

Post a Comment