foerfarande foer at maerka i artikel med aotminstone i polyolefinyta och i artikel med that svarmaerke av soenderfallen polyolefin

摘要

The invention concerns a method of marking articles having a polyolefin surface by exposure to a laser beam. The polyolefin contains a sufficient amount of a laser radiation absorbing substance for decomposing the polyolefin so that a black mark of decomposed polyolefin will be formed. …??The laser radiation absorbing substance is a silicon compound, preferably a metal silicate, e.g. calcium-metasilicate or kaoline. …??The invention also comprises an article having a polyolefin surface provided with a black mark of decomposed polyolefin formed by a laser beam.