Overview
EN ISO 3262-1:2020 - "Extenders - Specifications and methods of test - Part 1: Introduction and general test methods" (ISO 3262-1:2020) is the introductory part of the ISO 3262 series. Published by CEN/ISO in 2020, it defines the term extender and specifies the general sampling and test methods used as the basis for the subsequent parts of the ISO 3262 series. This part supersedes earlier editions and focuses on extenders for paints, related coating materials and other applications where extenders modify physical properties.
Key topics and technical requirements
- Definition of extender: Extenders are granular or powdered materials, practically insoluble or only slightly soluble in the application medium, used to modify physical properties.
- Sampling: Requires representative sampling according to ISO 15528 to ensure test results reflect the product batch.
- General test methods included as referee procedures:
- Comparison of colour - a visual referee method (with allowance for agreed instrumental methods such as CIE Lab* per ISO 11664-4; ISO 18314-1 for near-white hue assessment is noted).
- Determination of loss on ignition (LOI) - ignition at 1 000 ± 25 °C to constant mass, with calculation of mass loss expressed as percent.
- Determination of calcium and magnesium contents - chemical titration procedures including required reagents (e.g., HCl, EDTA solution), indicators (Calcon, Eriochrome black T), and apparatus; reagents are specified with CAS numbers.
- Normative references: Laboratory glassware and analytical methods referenced include ISO 385, ISO 648, ISO 787-2, ISO 1042, ISO 3696, ISO 3819 and ISO 15528.
Practical applications
- Ensures consistent quality control for raw extenders used in paints, coatings and related materials.
- Provides standardized test methods for vendors, manufacturers and QC laboratories to verify physical and chemical properties (colour, volatile content, LOI, Ca/Mg).
- Forms the foundation for product specifications in supply contracts and regulatory compliance for pigment and extender materials.
Who should use this standard
- Paint and coatings manufacturers and formulators
- Raw material and extender suppliers
- Quality control and analytical laboratories
- Standards committees and procurement specialists specifying extender performance
Related standards
This standard is essential for anyone involved in specifying, testing or supplying extenders for paints and coatings, providing harmonized test methods and definitions to support reliable product performance and supply chain consistency.
