Sports and leisure shoes are the real trendsetters in the shoe sector, and new materials and designs are being developed all the time. And, according to machine builder Karl Mayer, the innovation cycles are largely influenced by double-bar raschel knitting technology (DR technology).

These double needle bar warp knitting machines produce spacer fabrics that have become firm favourites for manufacturing the footwear worn by sports enthusiasts and fashion-conscious people alike. More and more designs are also being produced, thanks to the use of piezo jacquard technology.

As a result of an in-depth analysis of the requirements of the shoe and sports sectors, Karl Mayer, the leading warp knitting machinery manufacturer, has given new impetus to the trend for multi-coloured effects with its RDJ 5/1 machine, operating in gauge E 24. The machine features a specific technical configuration and the distance between the trick plates is just 2 mm. The distance between the knockover comb bars can generally be set at between 2 and 8 mm.

The jacquard bar is threaded with black yarn, whilst the ground guide bars process the red yarn for the inside of the fabric and also yellow and blue yarn for the outer side. The beams needed to do this are produced in multiple colours to suit the pattern on the Karl Mayer DS OPTO EC warper. This flexible warp preparation machine combines direct and sectional warping, and thus enables multi-coloured sectional warp beams to be produced in a wide range of colours.

Bright colours and precise design

To produce an attractive, brightly coloured shoe fabric, the multi-coloured sectional warp beams are processed by the ground guide bars on both sides of the fabric to produce a design having a dense construction.

The jacquard bar places the black yarn to suit the lapping, and swings backwards and forwards between the needle bars in order to do this. The pattern is, therefore, based on a specific combination of colours and not, as previously, on the production of holes of varying sizes at different locations.

This principle enables the knitted look to be produced in bright colours and with precise design features – to create a shoe from a single piece. The contours of the shoe upper, as well as logos and lettering, can also be worked into the textile without any problems.

Efficient production

“This flat, hardwearing, double-layered fabric not only has a modern look with a variety of different designs, it can also be produced extremely efficiently,” the company explains.

“At a speed of roughly 740 courses per minute and a working width of 138", the RDJ 5/1 can produce the fabric for up to 150 pairs of shoes per hour – much more than can be produced by circular weft knitting machines, not to mention flat weft knitting machines.”

www.karlmayer.com