An electric cable comprising: - an electric conductor surrounded by a first layer comprising at least one winding of a mica ribbon, said mica ribbon consisting of mica particles deposited via a polymeric binder on a support, - a second layer comprising at least one winding of a polyimide ribbon, and - a third layer comprising at least one winding of polytetrafluoroethylene (PTFE) ribbon, the first layer being heat-treated at a temperature of at least 400°C, and the ratio R of the mass per unit length of PTFE over the sum of the masses per unit length of the polymeric binder and of the polyimide being such that: ∘ R is greater than or equal to 2 when the section of the electric conductor is at most equal to 0.2 mm 2, preferably comprised between 0.1 and 0.2 mm 2, ∘ R is greater than or equal to 4 when the section of the electric conductor is strictly greater than 0.2 mm 2, and strictly less than 0.6 mm 2, ∘ R is greater than or equal to 6 when the section of the electric conductor is equal to 0.6 mm 2, ∘ R is greater than or equal to 12 when the section of the electric conductor is strictly greater than 0.6 mm 2, preferably of at most 3 mm 2, the ratio R being calculated from the respective initial masses: ∘ of PTFE from the PTFE ribbon(s) (third layer), ∘ of polymeric binder from the mica ribbon(s) (first layer), and ∘ of polyimide from the polyimide ribbon(s) (second layer), the PTFE, polymeric binder, polyimide masses being defined as follows: ∘ the PTFE mass = (surfaces occupied by the non-sintered PTFE ribbon(s)) x (PTFE density), ∘ the polymeric binder mass = (mass of the mica ribbon(s)) x (polymeric binder content (%) of the mica ribbon(s)), with mass of the mica ribbon(s) = (surfaces occupied by the mica ribbon(s)) x (mica density) ∘ the polyimide mass = (surface occupied by the polyimide ribbon) x (polyimide density) x (polymide content (%) of the polyimide ribbon). - an electric conductor surrounded by a first layer comprising at least one winding of a mica ribbon, said mica ribbon consisting of mica particles deposited via a polymeric binder on a support, - a second layer comprising at least one winding of a polyimide ribbon, and - a third layer comprising at least one winding of polytetrafluoroethylene (PTFE) ribbon, ∘ R is greater than or equal to 2 when the section of the electric conductor is at most equal to 0.2 mm 2, preferably comprised between 0.1 and 0.2 mm 2, ∘ R is greater than or equal to 4 when the section of the electric conductor is strictly greater than 0.2 mm 2, and strictly less than 0.6 mm 2, ∘ R is greater than or equal to 6 when the section of the electric conductor is equal to 0.6 mm 2, ∘ R is greater than or equal to 12 when the section of the electric conductor is strictly greater than 0.6 mm 2, preferably of at most 3 mm 2, ∘ of PTFE from the PTFE ribbon(s) (third layer), ∘ of polymeric binder from the mica ribbon(s) (first layer), and ∘ of polyimide from the polyimide ribbon(s) (second layer), ∘ the PTFE mass = (surfaces occupied by the non-sintered PTFE ribbon(s)) x (PTFE density), ∘ the polymeric binder mass = (mass of the mica ribbon(s)) x (polymeric binder content (%) of the mica ribbon(s)), with mass of the mica ribbon(s) = (surfaces occupied by the mica ribbon(s)) x (mica density) ∘ the polyimide mass = (surface occupied by the polyimide ribbon) x (polyimide density) x (polymide content (%) of the polyimide ribbon).