KARACHI – Technical Color Solution, which supplies a range of technologies to the textile sector has teamed up with French textile machinery supplier Sedo Engineering to produce pre-reduced liquid indigo dyes using an electrochemical process.

The company, which is Sedo's agent in the country will install the machine at the second customer to buy Sedo’s ‘Smart Indigo’ technology behind Italdenim – the Milan-based jeans maker that has used electrochemistry to reduce indigo dyes for the past three years.

“We will start production tomorrow,” said Arshad Mohiuddin, CEO of Sedo's agent Technical Color Solution, who calls it “the most sustainable and greenest way to produce reduced liquid indigo.” The machine has been delivered to Kassim Textile Mills Ltd.

Ecotextile News has been following the development of this type of technology with interest since 2007 when researchers from the Leopold-Franzens University in Austria, together with fabric producer Getzner AG, dyestuff producer DyStar and textile machinery firm Thies first developed a workable electrochemical process for directly reducing indigo back in 2007.

This technology from Thies though was different in that it was an 'indirect' electochemical process using a mediator (iron complex) whereas the Sedo technology is  based on 'direct' electrochemical reduction and patented by The Swiss Federal Institute in 2006. The patent is owned by RedElec Technologie which licenses the technology on an exclusive basis to Sedo Engineering which makes commercial machines.

This technique directly reduces indigo powder in the dyebath so that dyes become soluble, and dyers can avoid the use of alkalis and powerful reducing agents that have been associated with wastewater pollution.