Incorporation of chip elements in a core yarn
View Patent ↗A fabrication method of a sheathed yarn includes the following steps: making a core run axially through a sheathing area; winding a sheathing fibre around the core in the sheathing area; and presenting a microelectronic chip fixed onto the core in the sheathing area. A polymer material is present between the microelectronic chip and the core when the sheathing step is performed. The polymer material creeps during the sheathing step to form a protective coating.
1. Fabrication method of a sheathed yarn, comprising the following steps:
providing a core and at least one microelectronic chip associated with sections of yarn;
providing a polymer material comprising fillers;
placing the at least one microelectronic chip and the sections of the yarn in contact with the core;
winding at least one sheathing fibre around the at least one microelectronic chip, the sections of yarn and the core in at least one sheathing area to form the sheathed yarn;
wherein the polymer material is present between the core and the at least one microelectronic chip before the sheathing fibre is wound around the at least one microelectronic chip and the core;
wherein the sheathing fibre is wound around the at least one microelectronic chip and the core so as to force creepage of the polymer material through turns of the sheathing fibre to form a protective coating around the at least one microelectronic chip preventing moisture from reaching the at least one microelectronic chip.
2. Method according to claim 1 , wherein the core is provided covered by the polymer material before placing the at least one microelectronic chip and the sections of the yarn in contact with the core.
3. Method according to claim 2 , wherein the core is partially covered by the polymer material, the covered areas defining receiving areas for the at least one microelectronic chip.
4. Method according to claim 1 , wherein the at least one micro-electronic chip is provided covered by the polymer material before placing the at least one microelectronic chip and the sections of the yarn in contact with the core.
5. Method according to claim 1 , wherein the fillers are formed by metallic material or by alumina.
6. Method according to claim 1 , wherein the polymer material is a thermoplastic material.
7. Method according to claim 1 , wherein an annealing step is performed on the sheathed yarn to polymerize the polymer material and to bond the core, the at least one microelectronic chip and sheathing fibre to one another.
8. Method according to claim 7 , wherein an additional annealing step is performed before placing the at least one microelectronic chip in contact with the core so as to soften the polymer material and bond the microelectronic chip.
9. Method according to claim 8 , wherein the core and polymer material respectively comprise first and second thermoplastic materials, the first thermoplastic material of the core creeping partially through the turns of the sheathing fibre.
10. Method according to claim 8 , wherein the polymer material is formed by a plurality of filaments braided with the core.
11. Method according to claim 1 , wherein a plurality of sheathing fibres are wound in superposed manner around the micro-electronic chip and wherein the quantity of polymer material and the quantity of sheathing fibres are chosen such that an external part of the sheathing fibres is devoid of polymer material after creepage.
12. Sheathed yarn comprising:
at least one sheathing fibre wound around a core;
at least one microelectronic chip sandwiched between the core and the at least one sheathing fibre;
a polymer material coating the at least one microelectronic chip, the at least one sheathing fibre comprising a peripheral area devoid of polymer material.