NARROW FABRICS

Abstract: A narrow fabric intended for use as part of a garment or appliance to be worn on part of the body of a wearer is provided with one or more areas of friction-generating material in the form of a relatively thin film. In a modification of the invention, the film is applied to an "open" fabric and is arranged to follow the structure of the fabric so that the film of friction-generating material exhibits a plurality of openings corresponding to openings in the fabric. The invention includes a process and apparatus for producing the fabric.

Description: NARROW FABRICS This invention relates to narrow fabrics and more particularly concerns narrow fabrics intended for use as part of a garment or appliance to be worn on part of the body of a wearer. There have been a number of proposals for providing on narrow fabrics one or more areas of a friction-generating material which serves to assist in retaining a garment or appliance in position during wear. Generally, these proposals have been in the field of ladies hosiery, particularly relating to stockings intended to be retained in position without any external means of support. In our prior application no.9520265.1 there is a review of the prior art in this field and deficiencies in the performance of prior art products are identified. In particular, many products are not sufficiently effective in retaining a garment or appliance in position, and the more effective products in this aspect often induce discomfort for the wearer and/or irritation of the skin in the area of contact with the friction-generating material . Our prior application no.9520265.1 puts forward a solution to this problem and products according to the invention claimed therein have proved to be commercially successful. Nevertheless certain wearers do suffer some discomfort and/or irritation even with these improved products. Further research has identified that the problems associated with such products can be even further reduced. Accordingly, it is a primary object of the present invention to provide an improved narrow fabric having an area of friction-generating material, said narrow fabric being for use as part of a garment or appliance intended for wear. A further object is to provide such a narrow fabric which has satisfactory friction-generating characteristics and which reduces wearer discomfort and/or irritation even further. According to the present invention we provide a narrow fabric intended for use as part of a garment or appliance to be worn on part of the body of a wearer, said narrow fabric being provided with one or more areas of friction-generating material in the form of a relatively thin film. The term "narrow fabric" is intended to refer not only to fabrics falling within a strict definition as used in the textile industry but to any fabric which has a longitudinal dimension considerably greater than its lateral, or average lateral, dimension. In the context of stockings, the term narrow fabric is intended to include fabric produced on a small diameter circular knitting machine. We have found, surprisingly, that the provision of a relatively large contact area does not, as would be expected, increase the irritation due to the prevention of exposure of the skin to atmosphere but tends to decrease the discomfort and irritation by spreading the load over a greater area and decreasing the load per unit area applied to the skin. The use of friction-generating material in the form of a film has also been found to provide a superior holding performance, so that garments tend to stay in position for longer periods. This, combined with the improved discomfort and irritation qualities, enables garments and appliances to be worn for longer periods which is an important consideration for the wearer. The effective surface area of the film should be relatively large as compared with the thickness. The effective surface area of the film may be limited by the lateral dimensions of the narrow fabric but the average lateral dimension of film area should be at least 25 mm, preferably 30 mm and more preferably 35 mm. Average lateral dimensions of 35 mm to 60 mm and especially 35 mm to 50 mm have been found to be particularly advantageous. The thickness of the film should be controlled and it is preferably substantially uniform throughout. Whilst some variation in thickness is acceptable any tendency for the variation in thickness to resemble a plurality of beads should be avoided in order to take full advantage of the invention. The average thickness should not exceed 0.5 mm, preferably 0.3 mm and more preferably 0.2 mm. Average thicknesses of 0.1 mm to 0.3 mm, especially 0.15 mm to 0.25 mm have been found to be particularly advantageous. The film is preferably continuous but it is not necessarily so; it may be interrupted in a longitudinal or a transverse direction. It is, however, necessary that the applied friction-generating material should be in the form of a relatively thin film and the interruptions should not be such as to divide the applied material into one or more beads. The films are believed to have an advantage in that they contribute less to the resilience of the coated fabric than relatively thicker beads or layers of friction-generating material and this is considered to be one of the factors in reducins the discomtort to the wearer. The friction-generating material is preferably a silicone elastomer and more preferably is a heat-curable silicone elastomer. Conveniently, the viscosity of the uncured silicone elastomer is 50,000 to 150.000 MPas. The invention includes a process for producing a narrow fabric intended for use as part of a garment or appliance to be worn on part of the body of a wearer, which comprises extruding a film of a curable friction- generating material onto a length of narrow fabric and curing the resultant film in situ on the fabric. Conveniently, the narrow fabric is fed past a longitudinally stationary extrusion head. In modification of the invention, the film is applied to an "open" fabric and is arranged to follow the structure of the fabric so that the film of friction-generating material exhibits a plurality of openings corresponding to openings in the fabric. It should be appreciated that in this modification of the invention the openings are determined by the nature of the substrate and not by external mechanical means controlling the application of the silicone coating. Such a structure of film has many advantages. In addition to providing a reduced resilience for given film dimensions, the openings provide access for air to the body of the wearer, both factors contributing to improved comfort for the wearer. The structure also improves the aesthetic quality of the fabric in that the film is virtually invisible from the reverse side of the fabric. It should be emphasised that not all the openings in the fabric need to have corresponding openings in the film of friction-generating material. For example, where the fabric is a lace it will usually comprise a design which will include a variety of openings of different shapes and sizes arranged in a pattern. The lateral dimensions of the film in this modification may be similar to those specified for the unmodified. The thickness should not exceed 0.5 mm and is preferably from 0.25 mm to 0.4 mm. According to a further aspect of the invention we provide a process for producing a narrow fabric intended for use as part of a garment or appliance to be worn on part of the body of a wearer, which comprises extruding a film of a curable friction-generating material onto a length of narrow fabric having a plurality of openings therein, directing at least one jet of gas onto the fabric in the region of the extruded film so as to produce openings in at least the areas of openings of relatively larger dimension in the fabric and curing the resultant film in situ on the fabric . The narrow fabric having a plurality of openings therein may be a lace. The or each jet is preferably relatively wide in comparison to its length, the width of the jet being determined by the lateral area of the fabric in which it is desired to produce openings in the film. The gas is conveniently air and is preferably comparatively dry clean air since contaminants may adversely affect the curing of the friction-generating material . The or each jet of gas may be operated so as to act on only selected areas of a fabric where an open structure is required. The application of the film and its subsequent treatment can be arranged so that openings in the film of friction-generating material will only correspond to the larger openings in the lace fabric and the film will be continuous in the regions of relatively smaller openings. Since these openings are relatively small the aesthetic appearance of the fabric is not adversely affected to any great extent. The friction-generating material is preferably a silicone elastomer and more preferably is a heat-curable silicone elastomer. Conveniently the viscosity of the uncured silicone elastomer is 50,000 to 100,000 MPas. The process can be adjusted to determine the size of openings which are present in the film. This can be achieved by controlling the pressure of the jet or jets of gas whilst selecting an appropriate viscosity of the silicone elastomer. Openings in the film corresponding to relatively small openings in the fabric can be produced by stretching the fabric to a desired extent until after the applied film has been cured. The invention is hereinafter further described with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a lace fabric having a film of friction-generating material applied thereto; Figure 2 is a schematic plan view of an apparatus suitable for applying the film of friction-generating material to a fabric; Figure 3 is a diagrammatic plan view of a lace fabric having a film of friction-generating material applied thereto with openings corresponding to larger openings in the fabric; and Figure 4 is a schematic plan view of a part of the apparatus shown in Figure 2 with the addition of means for providing a jet of gas. Referring to Figure 1 , the fabric 10 is a stretch lace intended for attachment to the top of a stocking. A continuous film 1 1 of a heat-cured silicone elastomer is applied thereto. The transverse dimensions of the particular embodiment shown are: fabric: 70 mm and film 40 mm with the film thickness being constant at about 0.15 mm. An apparatus suitable for carrying out the process is shown schematically in Figure 2. A length of narrow fabric 10 such as lace fabric, is fed continuously from a supply reel 20 to a take-up reel 24. A dry heat- curable silicone elastomer is fed from a supply chamber 21 to an extrusion head 22 which is arranged to extrude a film 11 of the heat-curable silicone elastomer onto the surface of the fabric 10. The silicone elastomer film is cured as it passes through the curing station 23. The product shown in Figure 3 comprises a length of stretch lace 10 having openings 12 of relatively large dimension. In the regions 13 of these relatively large openings it will be seen that the film 11 is confined to the textile material surrounding the openings whilst in the region 14 the openings are relatively small and the film is continuous. Figure 4 is a detail showing the provision of a nozzle 41 for producing a jet of air 42 which is directed from the underside of the fabric 10 in the region of the extrusion head 22 so that the desired openings in the film of friction-generating material are produced before the material is cured.

Claims: CLAIMS 1. A narrow fabric intended for use as part of a garment or appliance to be worn on part of the body of a wearer, said narrow fabric being provided with one or more areas of friction-generating material in the form of a relatively thin film. 2. A narrow fabric according to claim 1 in which the film is continuous. 3. A narrow fabric according to claim 1 in which the film is interrupted in a longitudinal and/or a transverse direction. 4. A narrow fabric intended for use as part of a garment or appliance to be worn on part of the body of a wearer, said narrow fabric being provided with one or more areas of friction-generating material in the form of a relatively thin film, said narrow fabric being an "open" fabric and the film of friction-generating material being arranged to follow the structure of the fabric so that the film of friction-generating material exhibits a plurality of openings corresponding to openings in the fabric. 5. A narrow fabric according to any of claims 1 to 4 in which the average lateral dimension of film area is at least 25 mm. 6. A narrow fabric according lo any of claims 1 to 4 in which the average lateral dimension of film area is at least 30 mm. 7. A narrow fabric according to any of claims 1 to 4 in which the average lateral dimension of film area is at least 35 mm. 8. A narrow fabric according to claim 7 in which the average lateral dimension of film area is from 35 mm to 60 mm. 9. A narrow fabric according to claim 7 in which the average lateral dimension of film area is from 35 mm to 50 mm. 10. A narrow fabric according to any of claims 1 to 9 in which the average thickness of the film does not exceed 0.5 mm. 11. A narrow fabric according to any of claims 1 to 3 or 5 to 9 in which the average thickness of the film does not exceed 0.3 mm. 12. A narrow fabric according to any of claims 1 to 3 or 5 to 9 in which the average thickness of the film does not exceed 0.2 mm. 13. A narrow fabric according to any of claims 1 to 3 or 5 to 9 in which the average thickness of the film is 0.1 mm to 0.3 mm. 14. A narrow fabric according to any of claims 1 to 3 or 5 to 9 in which the average thickness of the film is 0.15 mm to 0.25 mm. 15. A narrow fabric according to claim 4 in which the average thickness of the film is 0.25 mm to 0.4 mm. 16. A narrow fabric according to any of claims 1 to 15 in which the friction-generating material is a silicone elastomer. 17. A narrow fabric according to claim 16 in which the silicone elastomer is heat-curable. 18. A process for producing a narrow fabric intended for use as part of a garment or appliance to be worn on part of the body of a wearer, which comprises extruding a film of a curable friction-generating material onto a length of narrow fabric and curing the resultant film in situ on the fabric. 19. A process according to claim 17 in which the narrow fabric is fed past a longitudinally stationary extrusion head. 20. A process according to claim 18 or 19 in which the viscosity of the silicone elastomer prior to curing is 50,000 to 150,000 MPas. 21. A process for producing a narrow fabric intended for use as part of a garment or appliance to be worn on part of the body of a wearer, which comprises extruding a film of a curable friction-generating material onto a length of narrow fabric having a plurality of openings therein, directing one or more jets of gas onto the fabric in the region of the extruded film so as to produce openings in at least the areas of openings of relatively larger dimension in the fabric and curing the resultant film in situ on the fabric. 22. A process according to claim 21 in which the narrow fabric having a plurality of openings therein is a lace. 23. A process according to claim 21 or 22 in which the or each jet is relatively wide, the width of the jet being determined by the lateral area of the fabric in which it is desired to produce openings in the film. 24. A process according to any of claims 21 to 23 in which the gas is air. 25. A process according to claim 24 in which the gas is comparatively dry clean air. 26. A process according to any of claims 21 to 25 in which the or each jet of gas may be operated so as to act on only selected areas of a fabric where an open structure is required. 27. A process according to any of claims 21 to 26 in which the viscosity of the friction-generating material prior to curing is 50,000 to 100,000 MPas. 28. A process according to any of claims 21 to 27 in which the resultant film applied to the narrow fabric is as claimed in any of claims 1 to 3, 5 to 10, 16 or 17. 29. A process according to any of claims 20 to 28 in which the thickness of the film is 0.25 mm to 0.4 mm. 30. A process according to any of claims 20 to 28 in which the fabric is stretched when the film is applied and is maintained in a stretched condition until the friction-generating material has been cured. 31. A narrow fabric produced by a process as claimed in any of claims 21 to 30.

Inventors: CAIN MILES STEPHEN, FINDEN IAIN THOMAS ARTHUR, CAIN, MILES, STEPHEN, FINDEN, IAIN, THOMAS, ARTHUR
Applicants: CAIN MILES STEPHEN, FINDEN COATINGS LTD, FINDEN IAIN THOMAS ARTHUR, CAIN, MILES, STEPHEN, FINDEN COATINGS LIMITED, FINDEN, IAIN, THOMAS, ARTHUR
Application year: 1997
Main classification: D06B3
IPC codes: A41B11, D06B11, D06B15