Deformable FDM filaments with functional ribbons

A 3D item comprising 3D printed material, wherein the 3D item comprises one or more layers of 3D printed material, wherein:

• at least one of the layers comprises (i) a core, comprises a core material, wherein the core material comprises a first thermoplastic material, and (ii) a ribbon structure, comprising a plurality of rounds, wound around the core;
• nearest neighboring rounds of at least one set of two rounds have a non-zero second mutual distance thereby defining an inter-ribbon region, where the core material is exposed.

A filament comprising 3D printable material, wherein:

• the filament comprises (i) a first core comprising a core material, wherein the core material comprises a first thermoplastic material, and (ii) a first ribbon structure, comprising a plurality of rounds, wound around the first core;
• two nearest neighboring first rounds of at least one set of two first rounds have a non-zero first mutual distance thereby defining a first inter-ribbon region, where the core material is exposed.