Overview
ISO 2884-1:2024 defines a standardized procedure for the absolute measurement of dynamic viscosity of unpigmented paints, varnishes and binders using a cone-plate rotational viscometer at high shear rates. The method targets a shear-rate range of 9 000 s−1 to 12 000 s−1 and provides values that inform resistance to common application processes such as brushing, spraying and roller coating. The standard is applicable to Newtonian and non-Newtonian coating materials; for formulations with large dispersed particles, the measuring geometry must be adapted.
Key Topics
- Measuring assembly: Uses a cone-plate geometry designed for high shear. The cone angle should be as small as possible and not exceed 5°. A flattened (truncated) cone tip is used to avoid frictional influence at the tip.
- Sampling and preparation: Representative sampling is required (see ISO 15528) and sample preparation follows ISO 1513. Samples containing particles require a flattened cone tip and particle size should not exceed 10% of the removed cone-tip gap width.
- Operational conditions: Measurements are normally performed at (23 ± 0.2) °C, with ambient room conditions recommended by the device manufacturer (typical climate-controlled room: 23 ± 2 °C, RH 50 ± 5 %).
- Calibration and verification: The measuring assembly and temperature control must be calibrated and verified using a reference fluid (mineral oils; silicone oils not permitted). If reference measurements deviate by more than ±5 % from the setpoint, the assembly must be checked.
- Procedure and repeatability: Tests are performed in duplicate immediately after sample prep. Two determinations by the same operator in quick succession shall not differ by more than ±5 % from their mean. Measures to avoid errors (gap emptying, solvent loss, structural change) are specified.
- Test report: The standard requires a comprehensive report that references ISO 2884-1:2024 and documents sample identification, preparation, measuring device and geometry, calibration dates, measuring profile (temperature, duration), measured values (with units and shear rate), deviations, observations and operator identity.
Applications
ISO 2884-1:2024 is intended for quality control, product development and process evaluation where application behavior matters. Practical uses include:
- Predicting resistance to brushing, spraying and rolling during application
- Comparing formulations and binder performance under high shear
- Routine verification of production batches and lab-to-lab data exchange
Related Standards
- ISO 1513 - Examination and preparation of test samples
- ISO 15528 - Sampling of paints and varnishes
- ISO 3219-1 / ISO 3219-2 - Rheology vocabulary, symbols and general principles for rotational and oscillatory rheometry
By following ISO 2884-1:2024, laboratories and manufacturers can obtain reproducible, traceable viscosity data at high shear rates that are directly relevant to coating application performance.