Methods of manufacturing dampening layers

Abstract

A damping layer comprises a large number of yarns combined to form a textile, wherein at least some of the yarns are foamed synthetic yarns. Such a textile, which consists of a mix of foamed and non-foamed synthetic yarns, is relatively strong and light and can lead to more efficient use of the foamed material. The foamed synthetic yarn may be formed into upstanding loops which provide additional resiliency and damping.

Claims

1. A method for forming a damping layer by weaving a large number of yarns to form a textile, wherein at least some of the yarns are foamable synthetic yarns, and the yarns are first woven to each other and subsequently at least some of the synthetic yarns are foamed to form loops of foamed synthetic yarn upstanding from the textile and the loops of foamed synthetic yarn are open arches with the loops of adjacent foamed synthetic yarns engaging against each other and wherein at least one non-foamable yarn is arranged between adjacent foamable synthetic yarns.

2. The method according to claim 1, wherein the synthetic yarns to be foamed are incorporated into the textile in the form of plastic strips.

3. The method according to claim 1, further comprising causing the loops of adjacent foamed synthetic yarns to bond to each other during or subsequent to foaming.

4. A method for forming a damping layer by weaving a large number of yarns to form a textile, wherein at least some of the yarns are foamable synthetic yarns, and the yarns are first woven to each other and subsequently at least some of the synthetic yarns are foamed to form loops of foamed synthetic yarn upstanding from the textile and the loops of foamed synthetic yarn are open arches with the loops of adjacent foamed synthetic yarns engaging against each other, wherein the synthetic yarns to be foamed are interwoven as warp threads with weft threads of yarns which are not to be foamed, and each warp thread to be foamed alternately grips and drops several weft threads which are not to be foamed.

5. The method according to claim 4, wherein each warp thread to be foamed alternately grips a different number of weft threads which are not to be foamed than it drops.

6. The method according to claim 1, wherein the foamable synthetic yarns comprise polyethylene or polypropylene.

7. The method according to claim 1, wherein the foamable synthetic yarns are foamed by heating them to a temperature of at least 150 C.

8. A method for forming a damping layer by weaving a large number of yarns to form a textile, wherein at least some of the yarns are foamable synthetic yarns, and the yarns are first woven to each other and subsequently at least some of the synthetic yarns are foamed to form loops of foamed synthetic yarn upstanding from the textile and the loops of foamed synthetic yarn are open arches with the loops of adjacent foamed synthetic yarns engaging against each other, wherein some of the foamable synthetic yarns have properties which differ from those of the other foamable synthetic yarns.

Description

(1) The invention will now be explained by means of a number of examples and with reference to the attached drawing, in which:

(2) FIG. 1 shows a diagram of the stages of the method according to the invention,

(3) FIG. 2 shows a perspective view of a woven fabric comprising strips of plastic to be foamed which have been woven into the former as warp threads according to a first embodiment of the invention,

(4) FIG. 3 shows a perspective view of the fabric from FIG. 2 after the plastic strips have been foamed,

(5) FIG. 4 shows a top view of the fabric from FIGS. 2 and 3 after foaming,

(6) FIG. 5 shows a bottom view of said fabric after foaming,

(7) FIG. 6 shows a top view of another embodiment of a woven fabric comprising thin plastic strips to be foamed,

(8) FIG. 7 shows a view corresponding to that of FIG. 6 after foaming,

(9) FIG. 8 shows a perspective view of the fabric from FIGS. 6 and 7,

(10) FIG. 9 shows a diagrammatic cross section through the fabric from FIGS. 2-5 when used between a carpet and a hard surface, and

(11) FIG. 10 shows a view corresponding to that from FIG. 9 of the fabric from FIGS. 6-8 when used as a substrate.

(12) A method for forming a damping layer 10 according to an embodiment of the invention comprises the stages of supplying a first set of (synthetic) yarns 11 (box 1) and supplying a second set of synthetic yarns 12 (box 2). In this case, the synthetic yarns 12 of the second set are suitable for foaming. For the material for these synthetic yarns 12, consideration may be given to polypropylene or polyethylene. Suitable materials for the yarns 11 which are not to be foamed are not only polypropylene, but for example also jute, polyester, fibreglass, cotton and cellulose.

(13) In a subsequent stage (box 3), the yarns 11 which are not to be foamed and the synthetic yarns 12 to be foamed are connected to each other to form a textile 13. This connecting may be effected, for example, by means of a weaving technique, in which case the weft threads I are formed by the yarns 11 not to be foamed and the synthetic yarns 12 to be foamed are fed through the former as warp threads K.

(14) After the textile 13 has been formed, the synthetic yarns 12 to be foamed may indeed be foamed in a subsequent stage (box 4). This may be effected, for example, by heating these synthetic yarns 12 to a relatively high temperature, for example in the order of magnitude of 200 C. Of course, the yarns 11 not to be foamed have to be able to withstand such a high temperature, at which a foaming agent is activated in the synthetic yarns.

(15) Foaming the synthetic yarns 12 to be foamed may take place at the location at which the textile 13 is woven, but it is also conceivable that the textile 13 with the synthetic yarns 12 which have not yet been foamed and which at that point in time do not yet occupy a significant amount of space, is first transported (box 5) to a final location of use. At this location, the synthetic yarns 12 to be foamed can then be foamed, for example again by heating.

(16) In FIG. 2, an example of a woven fabric 13 can be seen where weft threads I of yarns 11 not to be foamed have been interwoven with a large number of warp threads K1, likewise of yarns 11 not to be foamed, and a smaller number of warp threads K2 of synthetic yarns 12 to be foamed. In this case, the latter warp threads K2 are in the form of strips of plastic 121 which are to be foamed. As can be seen in the figure, in each case several warp threads K1 of yarns 11 not to be foamed are arranged between two adjacent strips 121 of plastic to be foamed, as a result of which they are caused to contact each other after foaming, when the volume of the strips 121 is greatly increased, but they do not completely merge with one another. As a result thereof, a very open textile 13 is produced which has good water-draining properties. On the other hand, the textile 13 provides good stability, as the adjacent strips 121 are all connected to one another.

(17) FIG. 2 furthermore shows that each strip 121 of plastic to be foamed in each case grips a triple weft thread 113 and then drops three triple weft threads 113. As a result of this difference in the number of weft threads gripped and the number dropped, loops L.sub.B, L.sub.O of different dimensions are produced after foaming on either side of the fabric 13, as can be seen by comparing FIGS. 3, 4 and 5. As can also be seen from FIG. 3, the loops L.sub.B have the shape of upstanding open arches with openings formed between the loop and the remainder of the fabric 13.

(18) In another embodiment of the invention, the strips 121 of the plastic to be foamed are interwoven in a completely regular pattern (FIG. 6). In this case, each strip 121, as a warp thread, in each case grips as many weft threads as it drops. As a result thereof, thirteen loops L of identical dimensions are created on either side of the textile after foaming (FIG. 8). In this embodiment, relatively narrow strips 121 are used, as a result of which the textile 13 produced after foaming has a relatively fine grid of loops L.

(19) Although the strips to be foamed are evenly distributed across the textile in the illustrated examples, and are also made of the same material, both the distribution of the synthetic yarns to be foamed and their shape, type and characteristics may vary. The synthetic yarns can be extruded into various different shapes. Types of plastic of relatively high and relatively low density can be used. Thus, it is possible to form zones in the textile having different characteristics. Furthermore, the distribution and the characteristics of the yarns not to be foamed may also vary. Thus, at locations where the textile is expected to be subjected to significant loads, more yarns which are not to be foamed will be arranged, or yarns having a greater thickness or tensile strength. Additionally, while the above examples illustrate a woven fabric with loops of foamed material formed in the warp, the invention is not limited to such a configuration.

(20) As mentioned above, the damping layer 10 which is formed by using the woven foam can be used as an underlay between a hard surface 15 and a carpet 16 (FIG. 9). In this case, the damping layer 10 could be attached to the underside 17 of the carpet 16 as backing, but the carpet 16 may also be laid separately on the damping layer 10. The carpet 16 may form a floor covering or, for example, an artificial turf pitch. The damping layer 10 could also be used underneath types of hard flooring, such as parquet or laminate.

(21) The damping layer 10 may also be used in a different way for forming an artificial turf pitch 18. For example, synthetic fibres 19 in the form of artificial turf blades can be tufted into the openings of the textile 13 (FIG. 10).

(22) Other possible applications of the damping layer 10 are, for example, drainage mats, air-permeable mats, yoga mats, beach mats, etc. Technical uses of such layers include roof coverings, wall coverings or even as partition walls which can be used separately, provided the foam used is sufficiently stiff.

(23) Although the invention has been described above by means of an example, it will be clear that it is not limited thereto. Thus, it is also possible to incorporate a plastic which has already been prefoamed in the form of strips or yarns into the textile. As a result thereof, the additional stage of foaming the synthetic yarns after they have been connected to the textile is omitted. In this case, the foam may be supplied from a roll to a weaving machine and be cut into strips prior to entering said weaving machine which can then be woven into the fabric. Incidentally, the strips of material to be foamed may also be formed in this way. The method can then be carried out in a simpler way, although the resulting product is bulkier and therefore more difficult to transport than a textile comprising synthetic yarns which have not yet been foamed.

(24) The scope of the invention is solely determined by the following claims.