Yarns and fabrics may be dirty, contain natural waxes or oils, or have been treated with size or lubricants used in spinning, weaving or knitting. These can all interfere with dyeing, often leading to non-level results. Scouring is a large topic, and the process used depends on the fibre type and its condition. “True” scouring of greige cellulosic fabrics is typically done, after desizing, at the boil or at higher temperature in pressure vessels, with as much as 10 grams sodium hydroxide per litre of water, plus surfactants, and the process may last for several hours. Commercial scouring of wool may use solvents, similar to dry cleaning, as part of the process. White fabrics sold at retail have normally be scoured at the mill; “natural” fabrics usually have not (some “natural” fabrics have been scoured but not bleached).
Art dyeing literature often refers to what amounts to laundering as scouring. This is inadequate for greige fabrics, but often quite acceptable for “white goods”. A long machine wash with the hottest water possible, about a gram of soda ash per litre of water (about a teaspoon per gallon) and some (preferably optical brightener free) detergent, followed by two rinses is usually acceptable. Sodium hexametaphosphate may be helpful if the water is hard. Woven white cottons often contain starch that will not be removed by such a limited process.
Alkaline Enzyme Scouring of Cotton Textiles
The invention relates to a process for treatment of cellulosic material, as for example, knitted or woven cotton fabric, comprising the steps of preparing an aqueous enzyme solution comprising pectinase, treating the cellulosic material with an effective amount of the aqueous enzyme solution under alkaline scouring conditions; e.g., pH of 9 or above and a temperature of 50° C. or above, in a low calcium or calcium-free environment, yielding a modification of the cellulosic material such that exhibits an enhanced respond to a subsequent chemical treatment.
Traditionally, cotton scouring has required the use of harsh alkaline chemicals (caustic), extreme temperatures and large volumes of water. Expenses include not only the cost of the caustic and energy, but also the cost of treating waste water to remove residual caustic and by-products.
Today, textile producers have a new, effective alternative to chemical scouring with the advent of the Cottonase™ enzyme. This novel enzyme not only cleans better than chemical scouring, but also greatly reduces the need for extensive waste water treatment and energy consumption. The Cottonase™ enzyme is a versatile, economically viable and environmentally friendly alternative to chemical scouring in cotton preparation.
The invention relates to a process for treatment of cellulosic material, as for example, knitted or woven cotton fabric, comprising the steps of preparing an aqueous enzyme solution comprising pectinase, treating the cellulosic material with an effective amount of the aqueous enzyme solution under alkaline scouring conditions; e.g., pH of 9 or above and a temperature of 50° C. or above, in a low calcium or calcium-free environment, yielding a modification of the cellulosic material such that exhibits an enhanced respond to a subsequent chemical treatment.
Traditionally, cotton scouring has required the use of harsh alkaline chemicals (caustic), extreme temperatures and large volumes of water. Expenses include not only the cost of the caustic and energy, but also the cost of treating waste water to remove residual caustic and by-products.
Today, textile producers have a new, effective alternative to chemical scouring with the advent of the Cottonase™ enzyme. This novel enzyme not only cleans better than chemical scouring, but also greatly reduces the need for extensive waste water treatment and energy consumption. The Cottonase™ enzyme is a versatile, economically viable and environmentally friendly alternative to chemical scouring in cotton preparation.
How to Scouring Textile Fabric:
- Simply wash your fabric, this includes PFD fabric, in the washing machine in hot water with Soda Ash. Do not add any fabric softeners to the wash. If you must dry your fabric do so without any fabric softener sheets
- Using an large enamel or stainless steel pot, fill the pot at least half full and place one ounce of soda ash into the pot per pound of cotton or linen fabric/fiber.
- Place fabric into water, swish it around using a stainless steel spoon.
- Bring water to a boil!!!
- Adjust heat to a low boil/hard simmer and allow to boil for two hours. stir the fabric every 15 minutes or so t make sure that the fabric is being adequately scoured
- After two hours remove from heat source, allow fabric to cool down until the fabric is at room temperature.
- Remove the fabric from the water and rinse.
Posts
0 comments: