Process for seaming plastic parts with a laser beam

A process for joining plastic components comprises using a laser. A primary, thin walled plastic component is formed, which absorbs laser light, and which has a quality surface. The thin walled plastic is welded to a second plastic which is transparent to laser light. A process for joining plastic components comprises using a laser. A primary, thin walled plastic component is formed, which absorbs laser light, and which has a quality surface. The thin walled plastic is welded to a second plastic which is transparent to laser light. The temperature gradient between the plastic components is reduced by preheating the transparent plastic, so that it melts more quickly. Heat dissipation in the direction of the quality surface is limited. The laser light has a wavelength of 700-1200 nm.