Technical textiles and home furnishings include fabrics that must be manufactured in open fabric constructions but being slip resistant. These are referred to as leno fabrics. Known manufacturing processes only permit low speeds. DORNIER’s system EasyLeno® (patent applied), is a new development in leno technology bringing up to 100% higher performance potential on DORNIER weaving machines. The system is available for both DORNIER air-jet and rapier weaving machines.

Leno technology


Weaving a normal fabric warp ends lay parallel and cross over or under the filling thread whereas the warp ends are themselves crossed as well during leno weaving. That means, leno fabrics comprise a warp end and filling thread system just the same as normal fabrics. However, the warp end system is split into straight and looping warp ends. Straight warp ends are always under the filling threads and represent the lower shed during weaving. On the other hand, looping warp ends are always above the filling threads and represent the upper shed during weaving. Leno fabric cohesion is attained by positioning looping warp ends once on the left and once on the right of straight warp ends of a leno group. This leno interlace supports leno fabrics with non-slip, latticed cloth designs with open fabric construction in warp and filling direction.

Today, interlacing is attained using the inverted leno method that restricts weaving machine speed and causes excessive wear on leno heddle pairs.


The new DORNIER EasyLeno®-system

Contrary to the classic system, two needle bars moved by the existing weaving machine drive are used. Straight warp ends are drawn into a stationary needle bar (blue in the graphic). This bar is shifted once per weaving machine cycle the length of one leno pair to the right and once to the left. To create a leno interlace, the looping warp ends, drawn in the movable needle bar (grey in the graphic), just have to be moved up and down between upper and lower shed. Leno movement for warp ends and weaving machine reed beat-up are made with the movable needle bar in the lower shed. The reed (green in graphic) moves from the beat-up to the rearmost position at the same time when the movable needle bar moves from lower to upper shed. This means, slay movement also serves simultaneously as drive for reed and movable needle bar movement. This automatically ensures that reed movement is synchronous to shedding motion movement.

Flat bars separate the needles in the needle bar for the following tasks:

• Warp end can only spring past one needle for leno interlacing.
• The needles in the stationary needle bar can be held and driven in a substructure in the machine. No foreign elements penetrate the warp ends across the whole width.

Decisive advantages of this leno method:

• Weaving machine without superstructure.
• Normal front and readr shed, with option to read in a lease during style changes.
• Minimum warp end needle wrap that means gentle warp end processing, low needle wear and easy maintenance.
• Both thread systems, looping and straight warp ends have the same lift even with symmetrical shed. This means an even load for both thread systems that protects sensitive warp yarns such as glass.
• The high cleaning effort required on traditional glass weaving machines to maintain the demanded quality is no longer necessary - an additional time advantage.
• Filling break repair and warpchanges are simple and easy for the operator.
• High thread densities up to 20 threads/cm possible.
• Speed limits only from filling insertion system, machine width, warp and filling materials used, but no limit by the leno device. This supports insertion performance on wide air-jet weaving machines up to 2,300 m/min.
• Leno interlace via machine drive. Shedding machine, undermotions, shafts and heddles not necessary.
• System can be used on both DORNIER air-jet and rapier weaving machines.

EasyLeno® applications

This new method is suitable for all leno fabrics – from very light curtains to heaviest glass rovings.
Leno fabrics are mainly produced from materials such as glass, polypropylene, polyester yarns but also from aramide, linen yarns for home furnishings and technical fabrics.
In the home furnishings sector, curtains from polyester leno fabrics mainly on air-jet and rapier weaving machines in nominal widths 300 cm to 360 cm.

There are many applications for technical fabrics. For example, glass leno fabrics to reinforce plaster layers on house walls and as carrier material for separating and grinding discs, mainly produced on rapier weaving machines in nominal widths 200 cm to 240 cm. Polypropylene leno fabrics are used as non-slip textile fabrics in geotextile and agriculture sectors. This type of leno fabric replaces the foamed material coating as second backing for latex-free carpets or flooring. Here, air-jet weaving machines in nominal widths 400 cm to 540 cm are used.

Even though new on the market, several plants already use EasyLeno® technology on DORNIER air-jet and rapier weaving machines in industrial applications.


Further development for 1/1 fabrics

A further development of this technology supports weaving in plain and leno technology and creates a new dimension in flexibility. This allows curtain weavers to use the same weaving machine for leno fabrics and plain styles. This also opens up options for completely new creations for fabric design. For example, decorative and clothing fabrics with vertical stripes from plain and leno warp ends.