Obertshausen - Until now, producing hosiery with a dense surface has been dominated by weft knitting. Karl Mayer has now developed a new process on its RDPJ and DJ machine series to produce smooth, seamless and ladderproof warp-knitted hosiery.
The company says that virtually every style of ladderproof, seamless pantyhose can be produced by using the potential offered by warp knitting and for this purpose, it offers a selected range of double-bar jacquard raschel machines especially for the hosiery sector.
The RDPJ and DJ series are already used for the production of patterned pantyhose. The working width and number of guide bars are different on these two machines, but they are both said to be very efficient and extremely accurate. Their specific configuration has an effect on the operating speed, the fabric stability that can be achieved, the haptic characteristics of the textile, and the patterning possibilities. For example, large patterns can be worked by using more ground guide bars in conjunction with the jacquard bars, and by using yarns having different colours or constructions.
Generally speaking, double-bar jacquard raschel machines offer a wide range of production and design options. The RDPJ and DJ machines are extremely versatile when it comes to working the patterns and construction of the pantyhose. The style of the lower sections, including the foot, the contours along the leg, the body opening and the gusset can all be varied.
The ankles can either be left open like leggings, or alternatively, the foot section may be closed seamlessly. The foot can be worked in a variety of different styles - from conventional closed toes, through constructions having large net openings into which the individual toes can be pushed, to designs based on the style of gloves.
Different styles of borders in the body section can also be produced. For example, edges can be worked in the form of cuffs, reinforced zones create soft shape effects, and cut edges are no longer needed for sewing on the elastic tapes.
The product developers have also succeeded in using double-bar raschel technology to incorporate the gusset directly into the pantyhose. This, says Karl Mayer, has made an important contribution to increasing the comfort and above all the service life of the hosiery. This is a weak zone in many pantyhose because the seams in the gusset are subject to a great deal of stress.
All these different options for creating specific designs can be worked by selecting the appropriate lapping in conjunction with the threading-in arrangement.
The yarn tension and stitch density can also be changed on the double-bar jacquard raschel machine. This enables different diameters to be worked, so that the shape of the pantyhose follows the contours of the leg. Bit by bit, the diameter can be altered along the heel, calf, knee, thigh, bottom and body section to match the body?s anatomy ? which guarantees a perfect fit. The shape can be varied in this way by using the KAMCO? computer system with its Motion Control/Multi Speed facility.
Net-like and dense constructions
The machines can also produce open net constructions, intricate open-work patterns or simple stripes. The wide variety of patterns is produced by lappings, which are worked by two ground guide bars and the jacquard bars. A pillar stitch construction made from textured yarn is processed in the ground and a tricot construction is used in the jacquard area. The tricot can be changed to a pillar stitch or 2x1 lapping and is usually processed from core-spun yarn.
In addition to the pantyhose with its eye-catching designs made from a combination of different open-work constructions, the double-bar jacquard raschel machines can now produce fabrics having a dense construction. This opaque look is created by three new types of lapping developed by Karl Mayer.
Style one is achieved by the already known combination of a pillar stitch lapping of the ground guide bar and a tricot lapping of the Jacquard bars. Due to the individual displacement of each of the Piezo-Jacquard needles, it is possible to work transparent and dense fabric areas as desired.
The second article shows a somewhat finer, very soft and extremely dense fabric quality made of pillar stitch and 2 x 1 lap ? i.e. a patterning technique which does not allow any open work structures.
The third variant ? a double tricot lap ? is a standard lapping of a tricot machine. But the special feature is the threading of all the bars with half the gauge, resulting in a very soft, dense textile. In case of all three articles special attention was paid to the fact that the joint between the leg part and the trunk part is made by the Jacquard bars in a seamless and invisible.
With all three types, more needles are needed per piece when producing smooth pantyhose than when producing mesh patterns. This is because the open-work construction exhibits a high degree of stretch, which ensures that the hosiery fits well around the leg.
According to Karl Mayer, this smooth, warp-knitted pantyhose, with its flawless appearance and laddering resistance, has effectively extended the range of smooth, warp-knitted pantyhose that can be produced on the DJ and RDPJ series of machines.