The present invention discloses a method for laser welding of plastics, comprising the steps of providing a first plastic material to be welded comprising a compound capable of absorbing near-infrared light, positioning a second plastic material in intimate contact with the first plastic material, and activating a laser source emitting a wave length in the near-infrared spectrum to obtain attachments of the first and the second plastic material. The compound capable of absorbing near-infrared light is a dye derived from croconic acid.