Standard Specification
An international testing standard that describes the procedure for evaluating the deinking behaviour of printed paper products under alkaline conditions ensures that recycling plants receive highly recoverable materials. Compliance with ISO 21993 allows graphic designers and paper producers to determine the recyclability of new ink and substrate combinations before full-scale production. This assessment simulates industrial deinking processes to measure the brightness of the recovered pulp.
Deinking Evaluation
Laboratory trials run under this standard involve treating printed paper with specific chemicals and executing a froth flotation step to separate the ink from the fibres. The efficiency of the ink detachment and the subsequent brightness of the deinked pulp are measured using standard spectrophotometric methods. This protocol provides a repeatable environment that eliminates the variance found between different commercial recycling facilities.
It establishes a baseline that helps chemical and ink suppliers test their formulations against a globally accepted benchmark.
Compliance Threshold
Print products that meet the requirements of this specification are designated as recyclable, reducing the risk of contamination in commercial recovered paper streams. Packaging boards and printed materials must achieve high dirt-exposure ratings to avoid being classified as non-recyclable. This threshold ensures that recycled pulp retains enough brightness to be used in high-quality packaging grades.
