Abstract: Synthetic filaments having a dull appearance and a feel similar to that of natural fibers, as well as a process for making same, are disclosed. The filaments have an integral skin-core structure, with the core formed of oriented dense polymer and the skin formed of the same polymer, in a fibrous and vesicular form. The filaments are produced by spinning the filaments and quenching the filaments while in the molten state in an inert cooling medium having a temperature of less than 100.degree.C. The inert cooling medium is a swelling agent for the polymer at temperatures above the polymer solidification point and a non-swelling agent for the polymer at temperatures less than 100.degree.C, the degree of swelling progressively decreasing with the decrease of the polymer filament temperature from the polymer solidification temperature to the temperature of the cooling medium.