Patent ID: 8075725

Claim:
A method of contour-welding three-dimensional thermoplastic molded articles, comprising: moving a laser-absorptive join partner and a laser transmissive join partner into contact with one another in the vicinity of a three-dimensional outline that is to be co-welded; heating the join partners in a process consisting of exposing the laser-absorptive join partner to radiation in a welding area by a laser welding beam and transmitting the laser welding beam through the laser transmissive join partner to weld together the join partners; and additionally and simultaneously exposing the laser transmissive join partner in the welding area to an electromagnetic secondary radiation from a source different from a laser and selected from the group consisting of IR and UV radiation for selective temperature increase of the welding area such that the temperature field in the welding area is homogenized with respect to a molten phase and an inter-layer plasticizing zone of the join partners, wherein the secondary radiation comprises at least beam fractions that deviate from the wavelength of the laser welding beam.