WO2017102615A1

WO2017102615A1 - Method for manufacturing a panel of fabric and kit for creating a wearable electronic item

Info

Publication number: WO2017102615A1
Application number: PCT/EP2016/080565
Authority: WO
Inventors: Andrew Morgan
Original assignee: J & P Coats Limited
Priority date: 2015-12-18
Filing date: 2016-12-12
Publication date: 2017-06-22
Also published as: GB201522378D0

Abstract

A web of textile material has one or more conductive filaments which are insulated within a coating, and an electrical contact pad situated adjacent one or more of the insulated filaments and attached to the web. The insulating coating comprises a material which is soluble by means of a solvent and wherein the contact pad and remaining material within the textile web are not soluble in the solvent.

Description

METHOD FOR MANUFACTURING A PANEL OF FABRIC AND KIT FOR CREATING A WEARABLE ELECTRONIC ITEM

BACKGROUND OF THE INVENTION

The present invention relates to textiles which may be used in connection with wearable electronics.

In addition to watches and headphones, for example, there is an increasing demand for textile garments which incorporate or are capable of incorporating electronic items or functionality. Textile webs used in wearable electronic clothing or other items typically possess conductive filaments, typically of carbon, steel or silver-coated polymers. Where the textile web is required to have surface conductivity, the filaments will be un-insulated. Equally, there are instances in which the conductive filaments are required to conduct electricity between two remotely-spaced conductive contact points on the web. In such circumstances, the filaments must be insulated between the contact points and capable of forming good electrical contact at the contact points. Notwithstanding these electrical requirements, the insulated filaments will preferably have the many of the physical properties of a textile thread. Moreover connection of the conductive filaments in the thread will often need to be made after the conductive thread has been connected to or otherwise incorporated into a fabric.

SUMMARY OF THE INVENTION

One aspect of the present invention provides a web of textile material, one or more conductive threads comprising an electrically conductive core and an electrical insulating layer around the core, an electrical contact pad attached to the web, wherein the insulating coating comprises a material which is soluble by means of a solvent and wherein the contact pad and remaining material within the textile web are not soluble in the solvent.

Preferably, the conductive thread is attached to the web and the conductive core is exposed beyond the insulating layer in the region of the contact pad, with the exposed core being adhered to the contact pad by means of an adhesive. In a preferred embodiment the adhesive comprises a conductive material to ensure electrical connection between the core and the contact pad.

In one embodiment the thread is attached by virtue of being woven into the web; alternatively, the thread is attached to the web by stitching comprising a material which is not soluble in the solvent. BRIEF DESCRIPTION OF DRAWINGS

An embodiment of the present invention will now be described, by way of example, and with reference to the accompanying drawings, in which:

Figs. 1 to 3 are perspective views illustrating stages of an embodiment method according to the present invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now to Fig. 1 , a panel of fabric is made of two, woven textile webs 10, 12 laminated together. At one, distal end D of the panel, the upper web 12 has been removed and replaced by an electrically-conductive contact pad 14 which is attached to the lower web 10. The contact pad 14 is divided into contact areas by insulating strips 16. Electrically-conductive threads 20, which comprise a conductive core and an external insulating layer, are connected to the fabric panel. The threads 20 are connected to the panel such that they extend from the distal end D where they are connected to the electrically conductive contact pad 14, to a proximal end P, where they extend over the upper web 12. Connection of the threads 20 to the panel both over the upper web 12 and the contact pad 14 may be achieved in any suitable manner having regard to the materials, characteristics and properties of the panel as a whole, the upper web 12 and the contact pad 14. Thus, for example, connection may be achieved by means of gluing, spot welding (whether using heat or chemical welding) or stitching for example. In the present example, connection is achieved by means of stitches 30 looping over the threads 20 and into at least the upper web 12 or contact pad 14, and preferably also extending into the lower web 10 of the panel.

In an alternative embodiment, the threads 20 can be integrated into the textile panel, for example by weaving them into the upper web 12 for example, and then drawing them distally beyond the upper web 12 to extend over the contact pad 14.

Referring once again to Fig. 1 , the conductive core 40 of each of the threads 20 is shown, for the purposes of illustration, as extending proud of the insulation 42 and the proximal end P. In the present example the conductive core 40 is made of a plurality of fine conductive filaments though monolithic cores may be used where they have the requisite physical properties. In the present embodiment, the filaments are fine steel filaments. Filaments from other suitable conductive materials may be employed including copper, carbon or silver-coated filaments. The insulation layer 42 may be provided by braided, woven or wound insulating filaments or, alternatively, by a single moulded layer or coating. In the present embodiment the insulation layer 42 is provided by braided acetate filaments. Insulation layers of other braided, woven, or wound insulating filaments may be used. A preferable characteristic of the conductive thread 20 is that it behaves as a textile thread so the materials used to create it will preferably take this into account, together with the current and voltage levels which the conductive thread 20 is likely to be required to carry. The present embodiment of fine steel filaments in the conductive core 40 and an insulation layer of braided acetate filaments is one embodiment providing the desirable textile-like quality to the thread's properties.

The conductive threads 20 extend from the proximal side P of the panel, over the upper web 12 to the opposite, distal side D over contact pad 14 and are retained against, respectively, the upper web 12 and then the contact pad 14. The individual stitches 30 attaching the threads 20 to the panel traverse that distance to ensure good and reliable retention of the thread on the panel. However, because of the presence of the braided acetate filament insulating layer 42, the conductive core filaments 40 of the thread are not in contact with the conductive pad 14 in Fig. 1 .

Referring now to Fig. 2, to create electrical contact between the contact pad 14 and the conductive core 40 of the conductive threads 20, the braided acetate filament insulating layer 42 is then stripped from the conductive thread in the region of the contact pad 14 to lay bare the conductive core 40. Stripping the insulating later 42 from the conductive core 40 is a difficult operation to perform mechanically given that the conductive threads are stitched to the web and to the contact pad 14. In the present embodiment, the stripping process is achieved chemically by the use of a solvent which dissolves the insulating layer 42 but does not dissolve or otherwise damage the stitching 30 retaining the conductive thread 20 on the upper web 12 and the contact pad 14 or the material from which the panel including the upper web 12 is made. In the present example, where the braided insulating layer 42 is made of acetate filaments and the upper and lower webs 10, 12 may be of nylon, acetone solvent is used to dissolve the acetate braiding providing the insulation layer 42, stitching 30 or webs 10, 12. The webs 10, 12 of the panel and stitching 30 may be of any material that is not damaged or deteriorated by the solvent, and thus polyester, aramids, lycra, silk, cotton, wool or rayon for example may all be used as insulation - whether woven, wound, braided or otherwise).

Examples of other combinations of insulation on the one hand and solvent on the other are: Silk insulation with Sodium Hypochlorite solvent (where silk is not used in the web or stitching), Nylon insulation with Hypochloric Acid or Formic Acid solvent (where nylon is not used in the web or stitching) and Acetate insultation with Acetic Acid (where acetate is not used in the web or stitching). Referring now to Fig. 3, once the insulation 42 has been stripped and the conductive core 40 filaments have thereby been placed into conductive contact with the contact pad 14, the bare conductive filaments 40 are then adhered to the contact pad 14. One preferred method is to adhere the conductive core 40 to the contact pad by a suitable adhesive. One preferred such adhesive is a silicone-based conductive adhesive 50. This provides good mechanical connection of the stripped core 40 to the contact pad 14 and, at the same time, assists with the ongoing provision of conduction between the core 40 and the contact pad 14, such that the connection can withstand wear for the life of the garment on which the fabric panel is used. Thus, for example, the adhesive must typically withstand wear resulting from washing and flexing of the garment in this region. Preferably, thereafter, an insulating layer (not shown) is then provided over the top of the contact conductive silicone glue 50.

Alternatively, where the mechanical contact between the stripped filaments of the core 40 and the contact pad 14 is such as to provide a reliable conductive electrical connection between then assured, the glue may be of a insulating material such as epoxy resin or the like. This provides mechanical protection for the filaments and also insulates them from unwanted external electrical contact, potentially obviating the need for the provision of the further insulating layer over the contact pad, depending upon the nature and context of the usage of the panel

Claims

1 . A method of manufacturing a panel of fabric comprising a web of material, an electrically- conductive contact pad connected to the web and a thread attached to the panel, the thread having an electrically-conductive core and an insulating layer around the core, the method comprising the steps of:

adhering the thread to the panel such that it extends over the contact pad and is adhered to the panel in the region of the contact pad; and

applying a solvent to the insulating layer of the thread in the region of the contact pad thereby to dissolve the insulator in the solvent and render the conductive filament into electrically conducting contact with the pad.

2. A method according to claim 1 wherein the material of the web is not soluble in the solvent.

3. A method according to claim 1 or claim 2 wherein the material of the stitching is not soluble in the solvent.

4. A method according to claim 1 or claim 2 further comprising the step, after applying the solvent, of applying an adhesive to adhere the conductive core to the contact pad.

5. A method according to claim 4 wherein the adhesive comprises a conductive material and thereby ensures electrical contact between the core and the contact pad.

6. A method according to claim 4 wherein the adhesive of is of a non-conducting material.

7. A method according to any one of the preceding claims further comprising the step of covering the conductive core and adhesive with a further insulating layer.

8. A method according to any one of the preceding claims wherein the conductive core comprises a plurality of electrically conductive filaments.

9. A method according to any one of the preceding claims wherein the electrically conductive filaments comprise a material selected from the group consisting of carbon, copper, steel and silver.

10. A method according to any one of the preceding claims wherein the insulating layer comprises a plurality of insulating filaments which are wound, woven or braided over the conductive core.

1 1 . A method according to any one of the preceding claims wherein the conductive thread is connected to the web by one of stitching, gluing or welding.

12. A method according to any one of claims 1 to 10 wherein the conductive thread is woven into the web thereby to attach it to the web.

13. A method according to any one of the preceding claims wherein the combination of insulating layer, solvent and panel fabric are selected from the group consisting of:

silk insulating layer, sodium hypochlorite solvent wherein the panel and any stitches do not comprise silk;

nylon insulating layer, hypochloric acid or formic acid solvent wherein the panel and any stitches do not comprise nylon;

acetate insulating layer, acetic acid solvent wherein the panel and any stitches do not comprise acetate.

14. A kit for creating a wearable electronic item comprising:

a panel of fabric comprising a web of material and an electrical contact pad connected to the web;

a conductive thread comprising a conductive core and an insulating layer around the core, the thread being connected to the contact pad;

a solvent;

wherein the insulator is made from a material which is soluble in the solvent and the web is made from a material which is insoluble in the solvent.

15. A kit according to claim 14 wherein the conductive thread is stitched to the web and the stitching is made of material which is insoluble in the solvent.