Acid Wash:
Acid wash is a process in which a denim garment is treated with a bleach solution containing chlorine-soaked stones so that the color becomes faded and the material is softer. In case of acid wash, pumic stones are used. By the action of pumic stones, an irregular fading effect is developed on heavy garments like denim, thick canvas/twill, and sweaters. The pumic stones act a brushing action on the garment fabric surface. A fading effect may be developed on the garment by acid wash technique. The flow chart of the acid wash is given below.
Process Flow Chart of Acid Wash
BATCHING
↓
LOADING
↓
DESIZING (IF NECESSARY)
↓
CONDITIONING OF THE GARMENTS
↓
STONE PREPARATION
↓
ACID WASH
↓
NEUTRALIZATIION OF BY-PRODUCT (MNO2)
↓
NEUTRALIZATION
↓
FINISHING/SOFTENING
↓
DRYING
Acid Wash is a patented process and can be used only by permission. It is also a kind of stonewash. The wash is performed in two steps: in the first step, the garment is washed without water, and in the 2nd step with water. Soak volcanic stones in potassium permanganate solution. Stones absorb chemicals and become saturated. The stones are then dried in normal air or sun. The stones are ready for work.
Denim garments are now made ready for the wash. They are desized /detached in water in a tumble washer and dried in a spin dryer. The garments are put in a separate tumble washer filled with treated stones. Water is not added. Now run the tumble dryer wash the garments without water. Tumble washer is run to wash the garments without water. Stone will abrade the garments, especially, the exposed parts. Hidden parts will not be abraded.
After that, the garments are taken out of the tumble and transferred to another tumbler filled with water for washing and rinsing. After rinsing is over, the prominent acid wash effect will show up. The treated stones carry the chemical to bleach the exposed parts and bleach them to white. But the hidden parts remain untouched. Whitening agents are often added to water during rinse to make the white color in the blue jeans whiter to display acid wash.
Author of this Article: Rahat Khan Dept. of Apparel Manufacturing Atish Dipankar University of Science and Technology Cell: +8801717781833 Email: [email protected]