Tuesday, December 15, 2015

Pre-Process Textiles for Dyeing with Supercritical Fluids

scCO2 for Scouring : Cleaning of yarns and fabrics done prior to dyeing or printing

Production of yarns and converting these into fabrics by weaving or knitting processes requires use of various oils, waxes, lubricants and other additives to facilitate in the fabrication steps.  The processing aids are removed from the textile to obtain high quality dyeing or printing on the textile. Processing aids are used for all textile materials – natural and man-made, though they may differ chemically depending on the material.

To learn more about using supercritical fluids to process textiles, visit the eCO2Dye site.

Tuesday, December 8, 2015

What is a Supercritical Fluid?

A supercritical fluid (SCF) is any substance above its critical temperature and pressure; the fluid has the properties of both gas and liquid while not exhibiting a distinct liquid or gaseous phase. Thus, an SCF is,

• Dense like a liquid to dissolve materials
• Has low viscosity, high diffusivity, no surface tension like a gas


Carbon dioxide is the most commonly used supercritical fluid and becomes supercritical at 31oC and 74 BAR. There are many applications for scCO2, including decaffeination of coffee, extraction of natural products, and waterless textile dyeing.

Carbon dioxide is environmentally friendly, non-toxic and in our case most of the COis internally recycled with very little vented to the atmosphere. scCO2 based operations represent a very “green” technology.