The Importance of Contamination Sorting from Uster Technologies Fiber Cleaning Expert
Current and future nonwovens quality issues are explored by Uster Technologies fiber cleaning expert Mario Siegenthaler. He shared his observations based on experience and on discussions with customers. Contamination is an important quality topic for nonwovens producers – whether using synthetic or natural fibers. Mario Siegenthaler, fiber preparation expert at Uster Technologies, here shares observations on latest progress in the field, based on his experience and on discussions with customers. He presents strong evidence of the growing importance of contamination sorting today and in future years.
What do you notice when visiting customers in the nonwovens sector?
Mario Siegenthaler: I see the speed of business increasing. Nonwovens producers face fast changes of products in shorter times, because of the range and variations in end -products and the increasing demand for smaller batch sizes. That means they need to be highly flexible if they are to be good partners for customers, especially those in quality-critical synthetic fiber applications. Often, each change of end-product requires completely different fibers to be used in the production process, and any materials remaining in feed ducts from previous runs could potentially impact on final product quality.
How can this risk be avoided without compromising production flexibility?
Mario Siegenthaler: To prevent unwanted residual fibers getting into the production process, they should be eliminated at the earliest possible stage – at fiber preparation. Uster Jossi Vision Shield N delivers impressive performance in its ideal location, directly after the fine opener. Here, the fiber cleaning system, with its unique imaging spectroscopes, can detect and eject any particle which shows the slightest difference in color from the main fiber. With contaminants such as black spots (e.g. rubber particles), detection and elimination can be guaranteed down to a size of one square millimeter. All shades of colored contaminants – such as polypropylene fragments, cotton fibers or any other material – can be reliably detected down to the same one square millimeter size. Melting points in synthetic fibers (slightly colored, yellowish in appearance) as small as one square millimeter can also be removed effectively.
We understand that controlling contamination is essential in fields demanding high quality standards?
Mario Siegenthaler: We believe the range of applications in which contamination control is vital will grow in future. The trend for using recycled fibers in the drive for sustainability in textiles certainly won’t stop at the gates of nonwovens mills. Goods made of recycled fibers bring attractive margins and healthy business, as long as quality requirements are fulfilled. However, it is a proven fact that recycled fibers are still today prone to infinite and inconsistent quality variations. Operating a high-performance contamination sorter in the production line is the best way to ensure an acceptable end-product.
What is the situation with nonwovens producers using natural fibers, specifically cotton?
Mario Siegenthaler: Producers using bleached cotton feel often unsure about meeting the required high quality standards. To minimize the risk of claims for contaminated end-products, some have opted to install two contamination sorters in a row, one after the other. But this certainly is not having the desired effect on increasing efficiency.
Why is it not smart to use two contamination sorters in tandem?
Mario Siegenthaler: Optimum performance from a fiber cleaning system is achieved when the fiber tufts are fully and homogeneously opened. For that reason, the Uster Jossi Vision Shield is positioned immediately after the fine opener. Placing a second cleaning system in line, without a tuft opener, will not give the desired cleaning performance.
What other general misinformation has been prevalent in the nonwovens industry?
Mario Siegenthaler: One wrong notion is that effective contamination control would slow down production speed. This is certainly not the case with Uster Jossi Vision Shield N. The system works with highest performance results and reliability at a throughput of 2,000 kg of fibers per hour.
What trends could nonwovens producers in the cotton business anticipate?
Mario Siegenthaler: One option would be to focus on bio cotton of course, and benefit from the sustainability trend in goods for cosmetic and care applications, for example. End-consumers will accept higher prices, and the natural color of the product – but definitely not contamination. The fact is that contamination in cotton – characteristic of the natural product – cannot be eliminated in the bleaching process in this case. And the fiber cleaning process must take over completely when no bleaching is involved. Needless to say, the contamination sorter’s performance and reliability are critical – in addition to its technical superiority – in eliminating a minimum of ‘good’ fiber with each contamination ejection. With Jossi Vision Shield N, Uster has the solution for producers intending to gain a foothold in this new market.
