The present invention relates to the use of a thermosetting polymeric powder composition in a 3D printing process to produce a 3D duroplast, wherein the composition comprises at least one curable polymeric binder material and at least one thermoplast having a Tg and/or Mp below the temperature provided in a pass of the printing process and wherein during each pass of the printing process said polymeric binder material is at least partially cured within the layer thus formed and also at least partially crosslinked with the previous layer. The invention furthermore relates to a 3D printing process using such a thermosetting polymeric powder composition and a 3D-printing product obtained when using such a thermosetting polymeric powder composition.