Bi-component fibres are fibres which consist of two different raw material components comprising the core and the sheath. Both components have different properties such as different fusion and melting temperatures. If a core of high melting temperature is coated with a sheath of low melting temperature e.g. PES or PP, then, using thermal processes, only the sheath will melt, forming joints between the fibres and other admixtures. These can be core polymer fibres with viscose fibres or other fibres from sustainable raw materials such as polylactic acid (PLA). Hereby numerous thermo-bonded non-wovens can be produced and, when recycled, can be thermally separated again.