GB2342930A

GB2342930A - Double weave fabrics

Info

Publication number: GB2342930A
Application number: GB9822754A
Authority: GB
Inventors: Penelope Joanne Lovatt
Original assignee: CAMBORNE FABRICS Ltd; INTERFACE FABRICS Ltd
Current assignee: CAMBORNE FABRICS Ltd; INTERFACE FABRICS Ltd
Priority date: 1998-10-20
Filing date: 1998-10-20
Publication date: 2000-04-26
Also published as: GB9822754D0

Abstract

A fabric 10 is woven with regions 12 of a double weave and separating regions 14 of single weave and the regions 12 include a shrinkable yarn in one of their plies so that on treatment after weaving, e.g. with heat or a wet-finishing process, the yarns shrink and the regions 12 adopt a bubble-like configuration.

Description

DOUBLE WEAVE FABRICS The present invention relates to double weave fabrics and to a method of making a double weave fabric.

According to one aspect of the present invention, a woven fabric that includes a plurality of regions that each comprise at least two layers that are separate from each other with at least two such regions being separated from each other in the general extent of the fabric by a single layer is characterised in that yarns in one of the layers in the regions have undergone a change in length after their weaving. The change in length may be between 15 and 25% and is preferably in the region of 20% The yarns in one of the layers in the regions may have undergone a greater change in length than yarns in the other layers in the regions. The ratio of the change in length of one yarn to another may be greater than 5: 6 and is preferably in the region of 2: 3. The yarn that has undergone less of a change in length than the other yarn may have changed its length by less than 20% and preferably it has changed its length by in the region of 15% All of the yarns in one layer may have been caused to undergo a change in length and all those yarns may have been caused to undergo the same change in length.

The layers in the regions may be of a different weave. For instance, one of the layers may be a 2/2 twill and the other may be a plain weave.

At least some of the yarns in one of the layers in the regions may be different from some of the yarns in the other layers of the regions and all the yarns in one layer may be different from all of the yarns in the other layer.

The change in length that has been undergone may be a reduction and that reduction may have been brought about by wetting or by heating or by any combination thereof.

The change in length may have been set, for instance, by heat.

The single layer that separates at least two regions that each comprise at least two layers may include yarns from both of the layers of the regions.

At least one of the regions may be surrounded by a single layer.

The regions may be arranged in rows or in columns or both.

The regions may be generally cylindrical.

The layers in at least one of the regions may be spaced from each other over at least part of their coextent.

According to another aspect of the present invention a method of making a woven fabric including a plurality of regions each comprising at least two layers that are separate from each other with at least two such regions being separated from each other in the general extent of the fabric by a single layer is characterised in that yarns in one of the layers in the regions are caused to undergo a change in length after their weaving.

The method may comprise causing the yarns in one of the layers in the regions to undergo a greater change in length than the yarns in the other layer.

The method may comprise all of the yarns in one layer having been caused to undergo a change in length, for instance, to the same extent.

The method may comprise weaving the layers in the region with a different weave, for instance with one of the layers having a 2/2 twill and the other layer being a plain weave.

The method may comprise weaving the fabric with polyester yarns and one of those yarns may be high stretch yarn. At least one of those yarns may be 100% polyester.

The method may comprise causing the change in length by causing a reduction in the length and the method may comprise bringing about the reduction by wetting.

The method may comprise causing the length of the yarns to be set after their change in length has been undergone and that setting may be achieved by heat which may be in the region of 170 C to 180 C.

The method may comprise weaving the fabric such that the single layer includes yarns from both of the layers of the regions.

The method may comprise weaving the fabric such that at least one region is surrounded by a single layer.

The method may comprise weaving the fabric such that the regions are regular or random in shape and layout or in rows or columns or both.

The method may comprise weaving the regions such that they are annular.

The method may comprise causing a change in length of the yarns in one of the layers to be such that the layers in the regions are spaced from each other over at least part of their co-extent.

The method may comprise wetting or scouring or heating the fabric or any combination thereof.

The present invention includes any combination of the herein referred to features or limitations.

The present invention can be carried into practice in various ways but one embodiment will now be described, by way of example, and with reference to the accompanying drawings, in which: Figure 1 is a plan view of part of a woven fabric; and Figure 2 is an enlarged side sectional view taken on the line 2-2 of Figure 1.

As shown in the figures, the fabric 10 comprises annular areas 12 of a double weave fabric that are spaced apart from each other in rows and columns with a single weave region between the double weave areas.

The single weave region 14 is woven by weft threads passing, alternatively, above and below each successive warp thread.

The double weave regions 12 are formed by keeping alternate warp yarns in a raised position, clear of a pick of a weft yarn and then, with the remaining warp yarns, causing a weft yarn to pass alternately above and below those remaining warp yarns. Then the warp yarns that have had a weft yarn passed between them are lowered to be clear of the next pick of a weft yarn and those warp yarns that were previously in a raised position are moved such that the next weft yarn passes alternately above and below them. This process is repeated to produce the annular areas comprising the double weave fabric.

The warp yarns are arranged such that two types of yarn are used with each first type of yarn being spaced from each other in the direction across the loom by a single second type of yarn. Similarly, each second type of yarn are spaced from each other by a single first type of yarn. The weft pick is arranged such that alternate picks are first and then a second type of yarn. With this arrangement the double weave regions can be formed such that the upper layer 16 is of a first type of yarn only in both the warp and the weft and the lower layer 18 is of the second type of yarn only in both the warp and weft.

The single weave region 14 may comprise alternate first and second types of yarn in both the warp and weft direction. As each warp and weft yarn is used in the single weave region 14, that region has a much tighter weave than the weave in the double weave areas 12.

It will be appreciated that the areas 12 of double weave could be made of any desired configuration and need not necessarily be annular. Furthermore, the double weave area 12 could have different weaves on the upper layer 16 as compared to the lower layer.

The first type of yarn is chosen such that its contraction characteristics, for instance, when subject to wetting or temperature increase, differs from those characteristics of the second type of thread. For instance, polyester yarns having different characteristics can be used as the first and second type of yarn.

A specific example will now be described.

The first type of yarn is chosen to be that sold under the TM 2/167 Trevira C. S. and the second type of yarn is chosen as 2/167 Powerstretch polyester. The Trevira is a flame retardant polyester yarn and both yarns may be 100% polyester.

In the double weave areas 12 the upper layer 16 is formed as a plain weave of Trevira and the lower layer 18 is formed as'a 2/2 twill of Powerstretch polyester. The single weave region is formed of a 2/2 twill containing both types of yarn. The stretch yarn only becomes "stretchy"when subjected to hot water between 70 C to 100 C. Consequently it is easy to weave flat under an even tension.

As the double weave region comprises two different types of weave a small 3-dimensional pocket is created.

After weaving, the fabric is processed through a wet finishing routine in which the yarns are dyed. This causes the Powerstretch yarn to shrink to a greater extent than any shrinkage of the Trevira yarn thereby enhancing the 3-dimensional effect of the pockets to create a "bubble". The Trevira may have shrunk by 14% and the powerstretch yarn may have shrunk by 21%. It will be appreciated that the weaves of the upper and lower layers could be the same with the bubbles still being created by this process. The Powerstretch yarn in the single weave region 14 will also shrink to bind the yarns closer together and to provide a framework for the pockets.

During the wet finishing process the yarns are dyed or, alternatively or additionally, scoured. As the Trevira and Powerstretch yarns take up the dye to a different extent, the top and bottom of the pockets will have different shades thereby enhancing the appearance of the product and providing a two tone product from a single dying process, with that two tone being visible from both sides of the fabric.

If desired the fabric can be optionally stabilised by heat setting the yarns by raising them to a higher temperature than that of the dying process, above the glass transition point of the polymer. This kills the elastic properties of the yarns to fix the fabric in the form that it is in. That temperature may be 180 C.

The fabric thus formed could be used, for example, in commercial interiors, in office and contract seating as well as in panel base systems of furniture. Apart from being aesthetically pleasing it can provide comfort to a person sitting on or resting against the fabric as a result of the resilient effect of the pockets as well as providing good acoustic fabric as the pockets absorb sound as a result of the resilient hollow form.

There may be 283.48 ends for each 10cm in the loom and 220 picks for each lOcm in the loom.

The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment (s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

CLAIMS 1. A woven fabric including a plurality of regions that each comprise at least two layers that are separate from each other with at least two such regions being separated from each other in the general extent of the fabric by a single layer characterised in that yarns of one of the layers in the regions have undergone a change in length after their weaving.
2. A fabric as claimed in Claim 1 in which the change in length is between 12 and 25%.
3. A fabric as claimed in Claim 2 in which the change in length is in the region of 20%.
4. A fabric as claimed in any of Claims 1 to 3 in which the yarns in one of the layers in the regions have undergone a greater change in length than yarns in the other layers in the region.
5. A fabric as claimed in Claim 4 in which the ratio of the change in length of one yarn to another is greater than 5: 6.
6. A fabric as claimed in Claim 5 in which the ratio is in the region of 2: 3.
7. A fabric as claimed in any of Claims 4 to 6 in which the yarn that has undergone less of a change in length than the other yarn has changed its length by at least 20%.
8. A fabric as claimed in Claim 7 in which the change in length is in the region of 15%.
9. A fabric as claimed in any preceding claim in which all of the yarns in one layer have been caused to undergo a change in length.
10. A fabric as claimed in Claim 9 in which all of the yarns in one layer have been caused to undergo the same change in length.
11. A fabric as claimed in any preceding claim in which the layers in the region are of a different weave.
12. A fabric as claimed in Claim 11 in which one of the layers is a 2/2 twill and the other layer is a plain weave.
13. A fabric as claimed in any preceding claim in which at least some of the yarns in one of the layers in the regions is different from some of the yarns in the other layers of the regions.
14. A fabric as claimed in Claim 13 in which all of the yarns in one layer are different from all of the yarns in the other layer.
15. A fabric as claimed in any preceding claim in which the change in length that has been undergone is a reduction.
16. A fabric as claimed in Claim 15 in which the reduction has been brought about by wetting.
17. A fabric as claimed in Claim 15 or 16 in which the reduction in length has been brought about by heating.
18. A fabric as claimed in Claim 18 in which the change in length is set.
19. A fabric as claimed in any preceding claim in which the single layer that separates at least two regions that comprise at least two layers includes yarns from both of the layers of the regions.
20. A fabric as claimed in any preceding claim in which at least one of the regions is surrounded by a single layer.
21. A fabric as claimed in any preceding claim in which the regions are arranged in rows.
22. A fabric as claimed in any preceding claim in which the regions are arranged in columns.
23. A fabric as claimed in any preceding claim in which the regions are generally cylindrical.
24. A fabric as claimed in any preceding claim in which the layers in at least one of the regions are spaced from each other over at least part of their co-extent.
25. A woven fabric substantially as herein described with reference to, and as shown in any of the figures.
26. A method of making a woven fabric including a plurality of regions each comprising at least two layers that are separate from each other with at least two such regions being separated from each other in the general extent of the fabric by a single layer characterised in that yarns in one of the layers in the regions are caused to undergo a greater change in length after their weaving.
27. A method as claimed in Claim 26 comprising causing the yarns in one of the layers in the regions to undergo a greater change in length than the yarns in the other layer.
28. A method as claimed in Claim 26 or 27 comprising all of the yarns in one layer having been caused to undergo a change in length.
29. A method as claimed in any of Claims 26 to 28 comprising weaving the layers in the region with a different weave.
30. A method as claimed in any of Claims 26 to 29 comprising weaving the fabric with polyester yarns with one of those yarns being a high stretch yarn.
31. A method as claimed in any of Claims 26 to 30 comprising causing the change in length by causing a reduction in the length.
32. A method as claimed in any of Claims 26 to 31 comprising causing the length of the yarns to be set after their change in length has been undergone.
33. A method as claimed in Claim 32 comprising causing the length of the yarns to be set by heat.
34. A method as claimed in any of Claims 26 to 33 comprising weaving the fabric such that the single layer includes yarns from both of the layers of the regions.
35. A method as claimed in any of Claims 26 to 34 comprising weaving the fabric such that at least one region is surrounded by a single layer.
36. A method as claimed in any of Claims 26 to 35 comprising causing a change in length of the yarns in one of the layers to be such that the layers in the regions are spaced from each other over at least part of their coextent.
37. A method of making a woven fabric substantially as herein described with reference to, and as shown in the accompanying drawings.
38. A method as claimed in any of Claims 26 to 37 for making a fabric as claimed in any of Claims 1 to 25.