ISO 21993:2020

Overview

ISO 21993:2020 - Paper and pulp - Deinkability test for printed paper products - specifies a basic laboratory test method to evaluate the deinkability of any printed paper product. The method simulates industrial single-stage flotation deinking under alkaline conditions using fatty acid‑based collector chemistry. ISO 21993:2020 is derived from INGEDE Method 11 and is designed to give an indication of how print products will perform in an industrial alkaline flotation deinking plant, while acknowledging that laboratory results are indicative rather than identical to full‑scale outcomes.

Key technical topics and requirements

• Scope and principle
  • Laboratory simulation of detachment, ink fragmentation and removal by single‑stage flotation under alkaline conditions.
• Equipment and chemicals
  • Lists general laboratory apparatus, pulping devices, flotation cells and analytical tools required.
  • Specifies use of fatty acid‑based collectors for flotation chemistry.
• Procedure steps
  • Sampling and identification of printed products, handling of non‑paper materials (inserts, adhesives), and optional accelerated ageing.
  • Pulp preparation (pulping, pH control, storage, dilution).
  • Flotation treatment and yield measurement.
• Specimen preparation and analysis
  • Preparation of filter pads, membrane filters and handsheets for measurement.
  • Analytical measurements including reflectance (brightness), filtrate darkening, dirt particle measurement and yield.
• Limitations
  • Method does not model additional industrial process stages such as dispersing, post‑flotation, washing, bleaching, cleaning and screening.
• Reporting
  • Requirements for test report content and example report structure are provided.

Practical applications and users

ISO 21993:2020 is useful for stakeholders across the paper and recycling value chain:

• Paper and board mills assessing recyclability of printed grades.
• Recycling plants and process engineers evaluating expected performance in alkaline flotation deinking.
• Laboratories and QA teams performing standardized deinkability testing.
• Paper product designers, printers and converters seeking to improve print and substrate choices for recyclability.
• Regulators and procurement officers requiring objective deinkability data for sustainability assessments.

Benefits include consistent laboratory evaluation of printed paper products, informed process design decisions and better communication between suppliers and recyclers about material performance.

Related standards

Normative references cited in ISO 21993:2020 include:

• ISO 187 (conditioning), ISO 638 (dry matter), ISO 1762 (ash on ignition),
• ISO 2469 / ISO 2470‑1 (reflectance/brightness), ISO 3689 (bursting after immersion),
• ISO 4119 (stock concentration) and ISO 5269‑1 (handsheet preparation).

Keywords: ISO 21993:2020, deinkability test, printed paper products, flotation deinking, alkaline deinking, fatty acid collector, paper recycling, laboratory test method.