At a time when the Tencel concept was being scaled up to produce basic staple fibre, future machines which would be capable of extracting higher value from the technology were also being considered. This 1988 diagram illustrates a possible layout for a machine capable of producing crimped staple fibre, tow and a range of bonded webs and nonwoven fabrics.
The proposal was first made for a viscose fibre in 1977 and involved a machine which would spun-lay tow onto a conveyor for washing, bonding and drying, the resulting dried and bonded web having 3 possible finishing processes. Fully bonded heavyweight webs could be sold into the absorbent viscose needelfelt market, a category which included both external and internal feminine hygiene - major viscose staple outlets. Bonded lightweights would become lint-free wipes. Temporarily bonded webs of discrete sinusoilally laid filaments could be pulled back into tow form after drying to give a highly crimped bulky tow which could packed and sold as a high quality tow or be cut to staple.
This "spun-laid" concept appeared to be easier using Tencel technology, where the vertically downward spinning system using large rectangular jets could be arranged to produce a ~3metre wide web on a conveyor-belt for washing. By 1988 the hydroentanglement bonding system and high capacity through air dryers could provide the web options.
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