GB2359826A - Warp knitted fabric - Google Patents

Description

2359826 WARP KNITTED FABRIC The present invention relates to a warp

knitted fabric, in particular, but not exclusively, a warp knitted fabric suitable for use for sports or leisure wear.

Warp knitted fabric for sportswear such as shirts for sports such as football, desirably are lightweight and have a good handle.

It is known to product such warp knitted fabrics including an elastomeric yam, such as Lycra (Registered Trademark), to improve the stretch characteristics of the fabric. To produce these fabrics on a warp knitting machine, the usual practice is to fully thread one of the guide bars of the machine with the elastomeric yarn.

Elastomeric yarns tend to be relatively expensive and so it is desirable to reduce the elastomeric yarn content in such fabrics without causing detrimental effects such as reducing the stretch characteristics to an unacceptable level.

A general aim of the present invention is to provide such a warp knitted fabric having a reduced elastomeric yarn content.

According to one aspect of the present invention there is provided a warp knitted fabric having a knitted ground fabric formed from a first set of non-elastomeric yarns, the knitted ground fabric having knitted stitches defining a plurality of wales and courses and a second set of elastomeric yams knitted in with the first set of yams so as to be plated with selected ones of said stitches on pairs of selected wales so as to define a first group of spaced pairs of wales alternating with a second group of pairs of wales, each adjacent wale in a pair of wales in said first group being interconnected by underlaps of said elastomeric yam, the number of yarns in said first set being greater than the number of yams in said second set.

Preferably each wale is common to a pair of wales in the first group and a pair of wales in said second group.

Preferably the knitted fabric includes a third set of non-elastomeric yarns knitted in with the first set of yarns so as to be plated with the io remainder of said stitches in order to produce underlaps connecting each pair of adjacent wales in said second group.

Preferably on selected courses, the second set of elastomeric yams are knitted in with the first set of non-elastomeric yams in order to produce plated stitches located in a wale located in an adjacent pair of wales in said first group.

Preferably the yarn count for the yarns in the first and third sets of yarns is the same.

Preferably the first set of yarns are constituted by a fully threaded front guide bar of a warp knitting machine.

Preferably the second set of yarns are constituted by a half threaded rear bar of a warp knitting machine, the rear bar being threaded on a 1 in - 1 miss basis.

Preferably the third set of yarns are constituted by a half threaded intermediate bar located between the front and rear bars. The intermediate bar being threaded on a 1 miss - 1 in basis.

2 Various aspects of the present invention are hereinafter described with reference to the accompanying drawings, in which:- Figures la to lc are diagrammatic views showing the lapping motions for a 3 bar fabric according to an embodiment of the present invention.

Figure 2 is a view similar to Figure 1 showing the lapping motions superimposed.

As indicated in Figure 1, the fabric according to the illustrated embodiment is knitted using three guide bars on a warp knitting machine.

A first guide bar is fully threaded with a first set of yarns 12 so as to supply yarn 12 to each needle of the knitting machine. The knitting machine is preferably a 28 gauge knitting machine.

The first set of yarns preferably comprise a flat polyester or a flat polyamide yarn having a yarn count which is preferably in the range of 22 to 167 dtex.

The lapping motion for the first guide bar are shown in Figure la and the lapping motion adopted preferably produces a ground fabric knitted structure having interconnected wales 40. This is achieved by adopting a lapping motion which feeds each yarn 12 to a different needle position (as represented by dots in Figure 1) on successive courses.

Preferably the lapping motion is 2-M-0 repeat although other lapping motions may be adopted. For example, a 3-411-0 repeat.

3 In order to provide the desired stretch characteristics for the fabric preferably in the coursewise direction, a second guide bar is partially threaded with an elastomeric yarn 14. The second bar is preferably half fully threaded on a 1 miss - 1 in basis. The elastorneric yarn is preferably a mono filament elastane having a yam count in the range of 22 to 78 dtex.

The lapping motion of the second guide bar is preferably opposed to the lapping motion of the first guide bar and preferably produces a 10 lapping motion for producing knitted stitches.

The lapping motion for the second guide bar is shown in Figure lc. Preferably the lapping motion is 1-0/1-2/1-0/2-3 repeat.

Accordingly, yarns 14 are knitted on the same needle as yarns 12 to produce plated stitches 43 on alternate courses (Figure 2).

In order to provide stability to the fabric a third guide bar is partially threaded with a non-elastomeric yarn 16. The third bar is 20 preferably half fully threaded on a 1 in - 1 miss basis.

The non-elastomeric yam 16 is preferably a flat polyester or flat polyamide having a yam count in the range of 22 to 167 dtex.

Preferably as shown in Figure lb, the third bar undergoes the same lapping motion as the second guide bar. Thus, on alternate course, the yams 12 and 16 are knitted by the same needle to produce plated stitches 46.

4 Accordingly, each wale 40, for those courses where the second and third guide bars undergo a 1-011-2 lapping motion, comprise plated stitches 43 alternating with plated stitches 46.

On selected courses, i.e. every 4' course in the preferred example, yarn 14 is knitted with yarn 12 on a needle located at two needle spacings away from the needle normally used. This creates a plated stitch 48 formed of a non-elastomeric yarn 12 and an elastomeric, yarn 14.

Accordingly, wales 40 are divided into two types. Viz wales 41 which contains plated stitches 43,46 and 48 and wales 42 which contains plated stitches 43 and 46 only.

Thus wales 41 contain a majority of stitches which are plated with a non-elastomeric yarn 12 and an elastomeric yarn 14 and wales 42 contain a minority of stitches which are plated with a non-elastomeric yam 12 and an elastomeric, yarn 14.

It will be noted, for a given wale 42, that it is joined to an adjacent wale 41 on one side by underlaps 50 of the elastomeric yarn 14 and is joined to the adjacent wale 41 on the opposite side by underlaps 51 of the non-eleastomeric yarn 16. Thus, in effect the wales divide into two groups, viz. a first group of adjacent wales FG connected by underlaps 15 and a second group of adjacent wales SG connected by underlaps 51. It will be noted that in the example of Figure 2, each wale is common to both groups FG, SG.

However, on every 4' course, adjacent wales 41 are joined to one another by underlaps 15 which, in effect provide an elastomeric bridge across the intermediate wale 42.

Thus, if the fabric is stretched in the coursewise direction underlaps 50 are stretched and act to pull the wales 41 and 42 (between which underlaps 50 extend) back together. In addition, underlaps 15 are 5 stretched and act to pull adjacent wales 41 together.

Accordingly, if the fabric is stretched in the coursewise direction, there is a consistency of recovery across the fabric in the coursewise direction despite some of the adjacent wales 41,42 being connected by lo non-elastomeric yarn underlaps 51.

In the illustrated example, the elastomeric bridges defined by underlaps 15 are formed on every 4' course. However, it will be appreciated that depending upon the stretch characteristics required in the fabric, that the elastomeric bridges formed by underlaps 15 may be formed at different course repeats, e.g. every 6' course or indeed may be omitted entirely.

If formation of underlaps 15 is not required, the second guide bar would undergo a regular lapping motion 1-0/1-2 repeat.

In a preferred example, the elastomeric yam 14 is about 40 dtex and preferably in a mono, filament bare yarn. Lycra (RTM) is a suitable elastomeric yarn.

In addition, the yarns 12 and 14 are preferably a textured multi filament polyester yarn. Preferably yarns 12,14 are each of 78 dtex/68 filament.

6 It will be appreciated that yarns 12 and 14 may be different, if desired.

In the example described above the first guide bar is preferably the front bar of the knitting machine, the second guide bar is preferably the rear guide bar and the third guide bar is preferably located in-between the front and rear guide bars.

Also, in the example given above, the second and third bars io undergo the same lapping motion and each have a half set of yarns. It will be appreciated therefore thata single second bar may be used which is fed with two beams of yarns 14, 16 which are threaded alternately along the second bar.

It is envisaged that the second and third guide bars may undergo different lapping motions in order to provide different pattern effects on the fabric.

With the adoption of the fabric construction according to the present invention it has been found that the elastomeric content of the fabric may be significantly reduced to less than 10% by weight of the fabric. In the preferred embodiment, the elastomeric content may be in the order of 4 % by weight of the fabric.

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Claims (10)

1. A warp knitted fabric having a knitted ground fabric formed from a first set of non-elastomeric yarns, the knitted ground fabric having knitted stitches defining a plurality of wales and courses and a second set of elastomeric yarns knitted in with the first set of yarns so as to be plated with selected ones of said stitches on pairs of selected wales so as to define a first group of spaced pairs of wales alternating with a second group of pairs of wales, each adjacent wale in a pair of wales in said first lo group being interconnected by underlaps of said elastomeric yarn, the number of yarns in said first set being greater than the number of yarns in said second set.

2. a fabric according to Claim 1 wherein each wale is common to a pair of wales in said first group and a pair of wales in said second group.

3. A fabric according to Claim 1 or 2 wherein the second set of elastomeric yarns are knitted in with the first set of non-elastomeric yams in order to produce plated stitches located in a wale located in an adjacent 20 pair of wales in said first group.

4. A fabric according to Claim 1, 2 or 3 including a third set of nonelastomeric yams knitted in with the first set of yarns so as to be plated with the remainder of said stitches in order to produce underlaps connecting each pair of adjacent wales in said second group.

5. A fabric according to Claim 4 wherein the second and third sets of yarns alternate with one another and in combination comprise the same number of yarns as the number of yarns in said first set.

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6. A fabric according to any preceding claim wherein the elastomeric yarn has a yam count in the range of 22-78 dtex.

7. A fabric according to any preceding claim wherein the elastomeric 5 yam constitutes less than about 10% by weight of the fabric.

8. A fabric according to any preceding claim wherein the first set of nonelastomeric yams are polyester or polyamide having a yam count in the range of about 22 to 167 dtex.

9. A fabric according to any preceding claim wherein the third set of nonelastomeric yams are polyester or polyamide having a yam count in the range of about 22 to 167 dtex.

10. A fabric substantially as herein described with reference to and as illustrated in the accompanying drawings.

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