Technology Offers

Cellulose-based micro- and super-microfibres produced as continuous yarn suitable for weaving and knitting

Abstract

A novel direct-wet-spin process was developed and patented by the German Institute of Textile Chemistry and Chemical Fibres (ITCF) in Denkendorf, which allows for the first time the cost-efficient production of micro- and supermicro-fibres of less than 0.1-0.5 dtex (fibre surface about 1-4 m²/g) from cellulose and cellulose-2.5-acetate in the form of a continuous fibre in a single-step process. The fibres can be stored as staple fibres or wound up as a continuous fibre for further processing.

Background

Micro- and super-microfibres fabricated from synthetic polymers are currently widely used. They are at present manufactured by a two stage process, producing bicomponent fibres. In this process the actual fibre material is spun together with a matrix component which is removed in a second step.

Problem

This process results in short super-microfibres which are in a loose and random form. They can therefore only be used for the manufacturing of nonwoven fabric with an equally random textile structure.
Cellulose and its derivatives cannot be melted and can therefore not be processed into micro- or supermicro-fibres using the classic bicomponent weaving process. So far it has therefore been impossible to produce such fine fibres and fabric.

Solution

A novel direct-spin process was developed and patented by the German Institute of Textile Chemistry and Chemical Fibres (ITCF) in Denkendorf, which allows for the first time the cost-efficient production of microfibres and supermicro-fibres of less than 0.1-0.5 dtex from cellulose and cellulose-2.5-acetate in the form of a continuous fibre in a single step process.
The attraction of this method is that for the first time this superfine fibre can be stored on a spool and subsequently processed further by weaving and knitting. This makes the fibres suitable for a broad range of applications, for example as filter material in industry and the household (tea bags), special paper or in hygiene applications as absorption material (tampons, ear buds) and the production of health care, cleaning and cosmetic articles (cleaning cloths, cotton buds).
The fibres exhibit a particularly large surface area (measured as surface area/g of fibres). Furthermore, it is possible to change and optimise the physical characteristics of the fibres via process control. This allows the production of superfine fabric which has the potential of innovative and improved characteristics.

Super-microfine cellulose fibres produced by direct spinning from ionic fluid.
Super-microfine cellulose fibres produced by direct spinning from ionic fluid.
Schematic of direct spinning. The cellulose which is dissolved in an ionic liquid is pushed through the micro-holes of a special spinneret and then coagulates into a fibre in the precipitation bath. The fibres can be stored as staple fibres or wound up as a continuous fibre and further processed.

Advantages

  • Continuous yarn of micro- and supermicro-fibres (< 0.1-0.5 dtex) based on cellulose
  • Direct spin process: one step, cost efficient
  • Possibility to manufacture extremely fine woven fabrics
  • Increased fibre surface area and improved, tunable fibre characteristics

Application

Manufacture of fibres, fabric, filters, special papers, hygiene article and cosmetics or further absorbing materials.

Exposé
Contact
Dr. Frank Schlotter
TLB GmbH
Ettlinger Straße 25
76137 Karlsruhe | Germany
Phone +49 721-79004-0
schlotter(at)tlb.de | www.tlb.de
Development Status
Proof of concept / TRL3
Patent Situation
DE 102012005489 B4 granted
Reference ID
11/095TLB
Service
The Technologie-Lizenz-Büro GmbH is in charge of the exploitation of this technology and assists companies in obtaining a licence.