GB2069549A

GB2069549A - Stitch Bonded Fabric

Info

Publication number: GB2069549A
Application number: GB8004634A
Authority: GB
Original assignee: Cosmopolitan Textile Co Ltd
Current assignee: Cosmopolitan Textile Co Ltd
Priority date: 1980-02-12
Filing date: 1980-02-12
Publication date: 1981-08-26
Also published as: GB2069549B

Abstract

A two bar stitch bonded fabric can be given a marked transverse stripe effect by stitching threads of both warp systems together in the same wale in first groups of at least two courses and alternating said first groups with second groups in which threads of at least sone of said systems move into or over an adjacent wale or wales. Preferably, one bar knits a ground of pillar stitch with perhaps an occasional tricot stitch while the other bar, effects the transverse stripe effect. <IMAGE>

Description

SPECIFICATION Textile Fabric and Method This invention relates to stitch bonded fabrics.

Stitch bonded fabrics are made on stitch bonding machines which are based to some extent on warp knitting machines, though they have important differences that are dictated in part by the fact that they have to deal with fibre fleece. One such difference is that stitch bonding machines conventionally have one or two guide bars, whereas warp knitting machines usually have three or more.

A stitch bonded fabric has conventionally been regarded as an inexpensive but relatively low quality substitute for woven or knitted fabrics made whoily from yarn. Because it is composed of a fibre fleece stitched through with warp thread stitches in pillar, or occasionally tricot stitch in single bar machines, or in a combination of pillar stitch on one bar (the front bar) and tricot stitch on the other (back) bar, or perhaps tricot stitch on both bars of the two bar machine arranged so that the underlaps form a diamond pattern, the prospects for introducing anything other than somewhat humdrum surface patterning or textured effects have been considered distinctly unpromising.

For the most part, patterning or surface texture effects have been restricted to "missed thread" patterns. This introduces a warp-way stripe effect.

Attempts have been made to introduce weft-way effects. Only very recently, however, have such attempts produced "convincing" results-that is to say, produced effects which effectively mask the characteristic stitch bonded appearance and introduce an appearance more akin to regular woven or knitted cloths.

The present invention produces just such a weft-way effect that is at once suggestive of more expensive and attractive fabrication methods, yet leaves the strength, stability and above all the cost of production of the stitch bonded fabric unchanged.

The invention comprises a two bar stitch bonded fabric having a marked weft-way effect, in which threads of both warp systems are pillar stitched together in the same wale in first groups of at least two courses, said first groups alternating with second groups in which threads of at least one of said systems move into or over an adjacent wale or wales.

Said first groups may extend over different numbers of courses, while said second groups may extend over different numbers of courses and/or wales.

The front bar threads may be pillar stitched throughout the length, or substantially so, of the fabric.

The invention also comprises a method for making a stitch bonded fabric, comprising stitching front and back bar thread systems so that threads of both systems are pillar stitched together in the same wale in first groups of at least two courses alternating with second groups in which threads of at least one of said systems are traversed into or over an adjacent wale or wales.

The front bar may knit pillar stitch continuously, while the back bar knits groups of pillar stitch courses alternating with groups of courses in which the back bar threads are moved into or over an adjacent wale or wales.

Although the bars may be traversed on a short cycle such as may be provided by a pattern cam, it may be preferred to provide a pattern chain so that a long repeat can be used, which will enable quasi-random effects to be created.

Thus some of the inherent limitations of conventional stitch bonding machines can be overcome and interesting surface texture or pattern effects produced.

One embodiment of a stitch bonded fabric according to the invention will now be described with reference to the accompanying drawings in which: Figure 1 is a point pattern showing the stitch notation for front and back bars of a two bar stitch bonding machine, and Figure 2 is a view of the fabric produced according to the point pattern shown in Figure 1.

The point pattern shown in Figure 1 has separate sections for front and back bar stitches.

The front bar stitches are pillar stitches extending the length of the fabric. The pillar stitch has the desirable property if imparting warp-wise strength and dimensional stability to the fabric. Of course, either front or back bar can knit pillar stitch continuously, but it is preferred that it is the front bar that is allocated to this task, as this gives more flexibility of patterning. The back bar can then either knit or lay-in, since the front bar stitch lap will cover and hold down a laid-in thread of the back bar.

If desired, of course, the two bars can be alternately allocated the role of providing the pillar stitch ground.

In any event, in the illustrated embodiment, while the front bar is knitting pillar stitch, the back bar is knitting and laying in according to an extended pattern. The back bar threads form two courses C" C7 of pillar stitch, then the back bar threads are laid-in over two wales over the next two courses C3, C4. Back in the starting wale, the back bar threads then stitch three courses, C5, C6, C7 of pillar stitch, then four courses, Q, Cg, Ciao, areta taken up with laying-in.

Figure 2 shows how tension in the back bar threads (b) distorts the front bar pillar stitch row where the back bar threads are laid-in.

Of course, different combinations of the basic patterning units-namely, stitches, laid-in sections and thread floats-can be used in the back bar patterning.

Claims

1. A two bar stitch bonded fabric having a marked transverse stripe effect, in which threads of both warp systems are stitched together in the same wale in first groups of at least two courses

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Textile Fabric and Method This invention relates to stitch bonded fabrics. Stitch bonded fabrics are made on stitch bonding machines which are based to some extent on warp knitting machines, though they have important differences that are dictated in part by the fact that they have to deal with fibre fleece. One such difference is that stitch bonding machines conventionally have one or two guide bars, whereas warp knitting machines usually have three or more. A stitch bonded fabric has conventionally been regarded as an inexpensive but relatively low quality substitute for woven or knitted fabrics made whoily from yarn. Because it is composed of a fibre fleece stitched through with warp thread stitches in pillar, or occasionally tricot stitch in single bar machines, or in a combination of pillar stitch on one bar (the front bar) and tricot stitch on the other (back) bar, or perhaps tricot stitch on both bars of the two bar machine arranged so that the underlaps form a diamond pattern, the prospects for introducing anything other than somewhat humdrum surface patterning or textured effects have been considered distinctly unpromising. For the most part, patterning or surface texture effects have been restricted to "missed thread" patterns. This introduces a warp-way stripe effect. Attempts have been made to introduce weft-way effects. Only very recently, however, have such attempts produced "convincing" results-that is to say, produced effects which effectively mask the characteristic stitch bonded appearance and introduce an appearance more akin to regular woven or knitted cloths. The present invention produces just such a weft-way effect that is at once suggestive of more expensive and attractive fabrication methods, yet leaves the strength, stability and above all the cost of production of the stitch bonded fabric unchanged. The invention comprises a two bar stitch bonded fabric having a marked weft-way effect, in which threads of both warp systems are pillar stitched together in the same wale in first groups of at least two courses, said first groups alternating with second groups in which threads of at least one of said systems move into or over an adjacent wale or wales. Said first groups may extend over different numbers of courses, while said second groups may extend over different numbers of courses and/or wales. The front bar threads may be pillar stitched throughout the length, or substantially so, of the fabric. The invention also comprises a method for making a stitch bonded fabric, comprising stitching front and back bar thread systems so that threads of both systems are pillar stitched together in the same wale in first groups of at least two courses alternating with second groups in which threads of at least one of said systems are traversed into or over an adjacent wale or wales. The front bar may knit pillar stitch continuously, while the back bar knits groups of pillar stitch courses alternating with groups of courses in which the back bar threads are moved into or over an adjacent wale or wales. Although the bars may be traversed on a short cycle such as may be provided by a pattern cam, it may be preferred to provide a pattern chain so that a long repeat can be used, which will enable quasi-random effects to be created. Thus some of the inherent limitations of conventional stitch bonding machines can be overcome and interesting surface texture or pattern effects produced. One embodiment of a stitch bonded fabric according to the invention will now be described with reference to the accompanying drawings in which: Figure 1 is a point pattern showing the stitch notation for front and back bars of a two bar stitch bonding machine, and Figure 2 is a view of the fabric produced according to the point pattern shown in Figure 1. The point pattern shown in Figure 1 has separate sections for front and back bar stitches. The front bar stitches are pillar stitches extending the length of the fabric. The pillar stitch has the desirable property if imparting warp-wise strength and dimensional stability to the fabric. Of course, either front or back bar can knit pillar stitch continuously, but it is preferred that it is the front bar that is allocated to this task, as this gives more flexibility of patterning. The back bar can then either knit or lay-in, since the front bar stitch lap will cover and hold down a laid-in thread of the back bar. If desired, of course, the two bars can be alternately allocated the role of providing the pillar stitch ground. In any event, in the illustrated embodiment, while the front bar is knitting pillar stitch, the back bar is knitting and laying in according to an extended pattern. The back bar threads form two courses C" C7 of pillar stitch, then the back bar threads are laid-in over two wales over the next two courses C3, C4. Back in the starting wale, the back bar threads then stitch three courses, C5, C6, C7 of pillar stitch, then four courses, Q, Cg, Ciao, areta taken up with laying-in. Figure 2 shows how tension in the back bar threads (b) distorts the front bar pillar stitch row where the back bar threads are laid-in. Of course, different combinations of the basic patterning units-namely, stitches, laid-in sections and thread floats-can be used in the back bar patterning. Claims

1. A two bar stitch bonded fabric having a marked transverse stripe effect, in which threads of both warp systems are stitched together in the same wale in first groups of at least two courses said first groups alternating with second groups in which threads of at least one of said systems move into or over an adjacent wale or wales.

2. A fabric according to claim 1, in which said first groups extend over different numbers of courses.

3. A fabric according to claim 1 or claim 2, in which said second groups extend over different numbers of courses.

4. A fabric according to any one of claims 1 to 3, in which said second groups extend over different numbers of wales.

5. A fabric according to any one of claims 1 to 4, in which the front bar threads are pillar stitched.

6. A method for making a stitch bonded fabric, comprising stitching front and back bar thread systems so that threads of both systems are stitched together in the same wale in first groups of at least two courses alternating with second groups in which threads of at least one of said systems are traversed into or over an adjacent wale or wales.

7. A method according to claim 6, in which the front bar knits pillar stitch, and the back bar knits groups of pillar stitch courses alternating with groups of courses in which the back bar threads are moved into or over an adjacent wale or wales.

8. A method according to claim 6 or claim 7, in which the patterning is controlled by a pattern chain to give a long repeat whereby quasi-random effects are created.