METHOD FOR MARKING PAPER AND APPARATUS FOR DETECTED MARKED PAPER

摘要

The invention relates to a procedure for the marking of paper and detection of marked paper for sorting when the paper is recycled, in which procedure a chemical tracer corresponding to the number of times the pulp has been used in the papermaking process is introduced into paper to be marked, and the tracer is detected in reclaimed paper by means of a detector sensitive to the tracer to allow reclaimed paper to be sorted for recycling according to the number of times it has been used.