Contamination-free, thanks to Uster Jossi systems

Cotton spinners no longer need worry about customer claims and demands for price reductions because of low-quality yarn. That might seem like wishful thinking – but it is now a reality, thanks to the comprehensive contamination solution offered by Uster Jossi systems.

As spinners know only too well, contamination in raw material comes in various forms, both natural and synthetic, depending on the origin of the cotton. And the impact on yarn quality can be calamitous. The fact that today´s yarn users have ever-increasing quality expectations makes the spinner´s challenge even tougher, and requires the use of the most effective cotton cleaning methods. For truly contamination-free cotton, Uster Jossi systems offer the best solutions available.

The Uster Jossi Vision Shield is the ultimate solution for detection and elimination of both natural foreign matter and synthetic contamination in raw cotton, drawing on four key concepts, outlined below. Located at the start of the yarn production sequence, immediately after the fine-cleaner in the spinning preparation section, the all-powerful Uster Jossi Vision Shield is at its most effective – at the point where the cotton tufts are most open.

Examining the material stream in this state, using the four detection principles together, means the Uster Jossi Vision Shield can make the spinner´s wish come true: the assurance of clean cotton, for best yarn quality and optimised productivity.

Four methods cover all contaminant types
Each of the four Uster Jossi detection methods offers specific benefits for a particular category of contaminant in the raw cotton. Together, they have all the bases covered for the spinner, ensuring that every potentially troublesome piece of foreign matter is pinpointed and removed.

Even the smallest impurities can lead to serious contamination, which is where the Imaging Spectroscope comes in. This method provides high-performance color contrast detection of very small or low-contrast impurities. Using microchip technology to view an extra-broad optical spectrum, the Imaging Spectroscope is far more sensitive than the human eye and can pick out material down to the size of a single hair.

For contaminants such as synthetics and fabric pieces containing brightener, the relatively simple principle of using UV light to detect fluorescence is highly effective. Here, the VTECT employs latest technology with durable LED sensors to guarantee optimum efficiency, making this instrument a vital basic component of contamination detection systems.

Since some polypropylene (PP) contaminants in raw cotton contain no brighteners, they cannot be detected by the VTECT, so an alternative is needed. This is where a technique known as the ´scattering effect´ comes into play. It works on the basis that light shining on cotton tufts forms a wide halo, whereas light beamed on to plastic forms a small reflection with sharp edges. This distinction is used to eliminate white polypropylene particles by Uster Jossi instruments – the only contamination detection system featuring this capability.

For a high-end solution with the unique ability to identify synthetics based on their physical properties, the Uster Jossi Magic Eye uses highly sophisticated multiplex spectroscope technology. By scanning the raw cotton tufts, it can identify the individual ´fingerprint´ of each type of plastic material, for separation and removal.

Clean cotton – and secure protection against hazardous risks. The Uster Jossi systems today are the result of 15 years of successful development by the former ownership, based on Swiss quality and technological excellence. Uster is committed to maintaining these principles to ensure spinners continue to benefit from contamination-free cotton, along with enhanced process and mill security.

In this regard, the Uster Jossi range includes syste