Using the latest generation of HPC texturising methods, which are of the highest priority regarding development at SwissTex Winterthur AG, the initial aim is to be able to produce such coarse, textile yarn in a singlestep process.

Finer and finer yarns, greater number of colours, more brilliant and vivid colours, and smaller batch sizes represent megatrends as regards BCF fibre production. These trends have been associated with the cotton and viscose industries for some time already, and now the BCF fibre industry is following suit.

Selection of fibrous material

Another megatrend of note concerns the selection of fibrous material. In a similar vein to the cotton industry with its BIO COTTON, the man-made-fibre industry has established the so-called (green fibre). Using starch produced from maize, which is converted into polylactide acid, the man-made-fibre industry has set up a "green" production line. The product is new and the demands on the machine components are high. The increased wear on the machine components is as important a topic as the process stability and spinning performance of the new polymer.

Consequently, SwissTex Winterthur AG collaborates with leading raw material and BCF producers, with the purpose of, on the one hand improving the process stability, and hence the profitability, and on the other, increasing the resistance of the components to wear. With regard to this, SwissTex has beentesting novel types of surface coatings, with the first prototype components for texturising being subjected to field trials at customers’ premises. The results have been extremely positive and the components will be released for sale at the start of 2012.

A further possibility for improving ecological conditions relating to products or use of raw materials is to recycle waste polymer. A simpler situation involves reusing waste produced by the spinning process, but in the ideal case, chips from recycled PET bottles would be used in BCF production with PET. The recycling of PET chips from the food industry presents difficulties, mainly in the treatment of polymer but also in creating a process, which is not sensitive to residual impurities found in recycled PET. In case of specific customer requests, SwissTex Winterthur AG is prepared to help develop concept solutions and offer suggestions, based on a specific project.

All yarn types produce on the same machine

The diversity of carpet yarns is increasing continually. As a result, it is becoming more and more difficult to cover all the titre ranges, which places additional demands on the machine manufacturers.

If BCF yarn with titre values exceeding 3.000 dtex (10 - 20 dpf), used in the production of so-called shaggy carpets, is required for one section of the market, another section of the market may demand BCF yarn with titre values lower than 600 dtex (6 - 10 dpf), used in the production of fine, thin carpets.

SwissTex Winterthur AG is working on extending the machine concept, so that all yarn types can be produced on the same machine.

Such fine-yarn titre values can exist at the extreme points of the overall and individual filament titre ranges for some coarse textile applications, such as involving upholstery. Using the latest generation of HPC texturising methods, which are of the highest priority regarding development at SwissTex Winterthur AG, the initial aim is to be able to produce such coarse, textile yarn in a singlestep process. In order to guarantee that the process remains economical, multifilament production procedures have to be run due to the reduced relative throughput per end.

6-ends yarn texturing unit

Using a 6-ends yarn texturing unit SwissTex Winterthur AG envisages being able to run such processes so that they are stable. The reduced relative throughput is compensated for here by the increased number of threads per position. In order to avoid the need for a complete processing step downstream for such textile yarn, it is sufficient to run this one-step process at a reasonable speed of approximately 3.000 m/min, despite the reduced relative throughput per thread, and this in turn guarantees process stability and improves profitability.

The company has made further preparations for this application with the conversion of its pilot plant in Winterthur. This will allow fine yarn with titre values up to 200 dtex (2 - 5 dpf) to be produced. Moreover, customer trials will be performed at the pilot plant in Winterthur using fibrous material that is as yet unknown on the market. Concerning fireproof equipment, for example, using oxygen-binding media directly in the spinning mass (no foam coating) appears to be promising.

SwissTex has already conducted a wide range of basic trials in this area, and is currently working on optimising the industrial process. These kinds of special, technical challenges place high demands on key components of the spinning mill, texturing unit, drafting system and winder.

New colouring concept

Yarn manufacturers are confronted with continually decreasing production batch sizes. Up to six colour changes per day has forced traditional production to the limits of profitability. Therefore, a solution is being sought on the market, as to how flexibility can be increased and at the same time how the quantity of waste arising from colour changes can be reduced to a minimum. Along with optimisation of components, SwissTex Winterthur AG is also addressing this challenge and seeking a customer-friendly solution - this may take the form of an entirely new colouring concept. Knowledge on this subject is being accumulated on their own premises, and this should lead to the first prototypes and a series of trials in 2012.

These trends, which are ultimately controlled by the end consumer and the yarn producers, all the way through to the machine manufacturers, indicate where SwissTex is heading. The company feels it has a commitment not only to follow these trends but also to move ahead of them, in order to carve out a clear market advantage for its customers. After all, only the success of its customers can guarantee the success of SwissTex.

(The feature has been contributed by Mr Markus Hilber, Project Leader Texturing, SwissTex Winterthur AG, Switzerland)