Conductive strands for fabric-based items
Strands of material may be intertwined using weaving techniques, knitting techniques, non-woven or entanglement techniques, or braiding techniques. Fabric that is formed from the strands of material may be used in forming a fabric-based item. The fabric based item may include electrical components. The strands may include conductive strands that form signal paths. The signal paths can carry electrical signals associated with operation of the electrical components. Each strand may have an elongated core and a coating. Strands may also include intermediate layers between the cores and coatings. The cores, intermediate layers, and coatings may be formed from polymer without conductive filler, polymer with conductive filler, and/or metal. A polymer core may be provided with recesses to help retain subsequently deposited layers such as a metal coating layer. The recesses may be grooves that extend along the longitudinal axis of the core.
1. A conductive strand for carrying signals within a fabric, comprising:
an elongated conductive core;
an intermediate layer that covers the elongated conductive core, wherein the intermediate layer has recesses that pass entirely through the intermediate layer; and
a conductive coating on the intermediate layer that extends through the recesses in the intermediate layer to directly contact the elongated conductive core.
2. The conductive strand defined in claim 1 , wherein the intermediate layer comprises a polymer layer with conductive filler.
3. The conductive strand defined in claim 2 , wherein the conductive filler shorts the conductive coating to the elongated conductive core.
4. A fabric-based item, comprising:
a fabric formed from intertwined strands, wherein the intertwined strands include a conductive strand; and
electrical components that are interconnected using a signal path formed from the conductive strand, wherein the conductive strand comprises:
a core;
a conductive coating layer; and
an intermediate layer between the core and the conductive coating layer, wherein the intermediate layer has a plurality of recesses, wherein the conductive coating has first portions in the recesses and second portions that are interposed between the recesses, wherein the first portions of the conductive coating have a first thickness, and wherein the second portions of the conductive coating have a second thickness that is less than the first thickness.
5. The fabric-based item defined in claim 4 , wherein the core is a conductive core.
6. The fabric-based item defined in claim 4 , wherein the core is a polymer core that includes a conductive filler.
7. The fabric-based item defined in claim 6 , wherein the conductive filler comprises metal particles.
8. The fabric-based item defined in claim 4 , wherein the plurality of recesses in the intermediate layer comprise longitudinal grooves.
9. A multi-filament strand for carrying signals within a fabric, the multi-filament strand comprising:
a core strand; and
a plurality of conductive strands wrapped around the core strand, wherein each conductive strand of the plurality of conductive strands comprises:
a polymer core; and
a conductive coating layer.
10. The multi-filament strand defined in claim 9 , wherein the core strand is a polymer core strand.
11. The multi-filament strand defined in claim 9 , further comprising:
a conductive coating formed over the plurality of conductive strands.