Pigment Printing

Printing are insoluble coloring matter mostly mineral origin have been used for the coloration of metal, stone, wood and textile material.

Basic Principle of Pigment Printing:

1. Pre-treatments.
2. Printing.
3. Dyeing (90-100ºC).
4. Curing (Cotton 140-160ºC; 3-5min and polyester 160-220ºC; 30-60sec).

Successful pigment printing systems are based on three equally important components such as:

1. Pigment dispersion.
2. Binder and cross-linking agents.
3. Thickeners and auxiliary agent giving the required rheology.

Pigment dispersion: Most of the pigments used in textile printing are synthetic organic materials except for carbon black, TiO₂ and white pigments, copper and aluminum alloy. When choosing synthetic pigments the principle brilliance and the coloring power of the pigments should be3 taken into consideration. Organic pigments must used:

1. Azo pigments (Yellow, Orange, and Red).
2. Halogenated copper (Blues, greens).

Binder system: The binder is a film forming substance made up of long-chain polymers which when applied to the textile material together with the pigments, produces a three dimensional linked network. The network is formed by curing, which usually consists of dry heat and a pH value of around 5, bringing about self cross-linking or reaction with suitable cross-linking agent. Elasticity and improved adhesion of the film to the fabric is achieved cross-linking.

Advantage of pigment printing:

1. Applicable to natural and synthetic fiber.
2. Easy applicable and less expensive.
3. No need of washing.

Disadvantage of pigment printing:

1. Wet and rubbing fastness is average.
2. Not controllable for the binder film.
3. Less abrasion.
4. Less comfort resistance.