Over the past few decades, different denim washing techniques have been developed and used on different materials to create a large variety of designs for trendy denim garments and jeans. Denim Manufacturers are always trying to achieve Special colour effects and washed looks in denim garments. The hand feel of the washed goods is relatively superior, which makes them suitable for leisurewear.
The results obtained from denim washing represent a combined effect of colour dissolution, destruction of the dye and mechanical abrasion, which sometimes causes the removal of surface fibers from the materials. Thus, surface dyed (ring dyed effect) colours in denim garments are more easily washed down during the washing processes.
Denim manufacturers apply a sulfur dye before the indigo dye, which is known as sulfur-bottom dyeing, to create a grey or yellow vintage-look cast in the fabric. Colour can also be applied to the fabric after the indigo dye. This process of over-dying can change the main cast, or it can be applied to specific areas to create ‘dirty denim’.
This is the most common and basic process used by jeans manufacturers for producing a washed-down look on denim garments. Towards the end of the seventies, pumice stones were discovered to accelerate the ageing process of indigo-dyed denim garments. Stone washing uses pumice stones to create the appearance of an aged pair of jeans. Abrasions and faded colour are typical outcomes.
Whiskering is typically done by hand using abrasive rods or sanding, Whiskering refers to thin fading lines formed from creases that are usually found on the front pocket area of jeans, that give the appearance of worn denim. They’re strategically placed to resemble areas that would naturally crease and fade over time—think across the thighs, crotch and back of the knees. It is one of the most important designs of a used look denim garment. Now a days it is a common drying process for denim wash.
Acid, ice and snow wash
Denim manufacturers don’t use acid in acid washing or ice washing process. Pumice stones pre-soaked in a bleach solution are used when tumble-drying denim. The results? Non-uniform colour and splotchy patterns popularized in the ’80s.
Rinse Wash or Mill Wash
The objective of rinse washing is to keep the fabric appears as dark as possible. The denim is desized width wise in open width washing machine and the dye is not washed out. A rinse wash is exactly what it sounds like, a quick rinse of water to help remove any excess dye. Jeans manufacturers use this process for dark wash jeans, this simple denim washing treatment helps preserve as much rich colour as possible.
Enzyme washing uses cellulases to degrade the cellulose found in denim. As denim is made of cotton, it too consists of cellulose. Cellulases can be used to give denim a worn look. Enzymes have opened up new possibilities in denim finishing by increasing the variety of finishes available. Enzyme washing will remind you of chemistry class. This process is an eco-friendlier alternative to stone washing. It gives you the look of aged denim with less risk of damaging the garment.
In bleach wash, a strong oxidative bleaching agent is added during the washing, with or without pumice stones. bleaching is used by jeans manufacturers to decolourise the dark blue shade by destroying the indigo dye molecules with oxidative bleaching chemicals Pumice stones are pre-soaked in a bleach solution and tumble dried with blue jeans to produce heavily faded or white patterns. A strong bleach can also be added during the washing process or applied locally by rubbing or spray.