Overview
EN ISO 787-11:1995 is an internationally recognized standard developed by CEN (European Committee for Standardization) that specifies the general method for testing pigments and extenders by determining their tamped volume and apparent density after tamping. This standard aligns with ISO 787-11:1981 and replaces the earlier ISO/R 787/11-1970 recommendation. It establishes a precise laboratory procedure to measure how pigments and extenders compact under standardized conditions, providing critical data for material characterization in paint, coatings, and related industries.
Key Topics
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Scope and Purpose
The standard defines a consistent, reproducible method to measure the tamped volume and apparent density of powdered pigments and extenders. These parameters are essential to evaluate bulk properties influencing material performance during formulation.
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Test Procedure
- Dry the pigment or extender sample in an oven at 105 ± 2 °C for 2 hours.
- Pass the dried sample through a 500 µm sieve to break agglomerates.
- Fill a graduated 250 ml measuring cylinder with the sample without forming air pockets.
- Weigh the filled cylinder and stopper with the sample.
- Place the cylinder in a tamping volumeter and tamp it by rotating cams approximately 1250 revolutions per step.
- Continue tamping until two consecutive volume readings differ by less than 2 ml.
- Record final tamped volume and calculate the apparent density.
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Calculation Formulas
- Tamped Volume (vt) in ml per 100 g using the measured sample mass and volume after tamping.
- Apparent Density (et) in grams per milliliter calculated from the mass and tamped volume.
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Apparatus Description
The tamping volumeter consists of a graduated measuring cylinder with stopper, a holder and shaft assembly with a cam mechanism, anvil, sleeve to reduce friction, and a revolution counter. The device ensures uniform tamping energy by controlled dropping of the cylinder to compact the sample.
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Test Reporting
Reports must include product identification, reference to EN ISO 787-11:1995, test results, any deviations from procedure, and date of testing.
Applications
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Paints and Varnishes Manufacturing
Enables quality control of pigments and extenders by assessing their packing characteristics, which affect suspension stability and processing behavior.
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Material Specification and Compliance
Provides a standardized method to specify powder bulk density properties for suppliers and end users, ensuring consistency in procurement and formulation processes.
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Research and Development
Facilitates comparative analysis of new pigment or extender materials with established ones, supporting formulation optimization and innovation.
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Powder Handling and Storage Optimization
Knowledge of tamped volume and density aids in designing appropriate packaging, storage conditions, and transport logistics.
Related Standards
EN ISO 787-11 is part of a comprehensive series covering general test methods for pigments and extenders, including:
- EN ISO 787-1: Comparison of colour of pigments
- EN ISO 787-2: Determination of matter volatile at 105 °C
- EN ISO 787-10: Determination of density - Pyknometer method
- EN ISO 787-23: Determination of density using centrifuge to remove entrained air
- EN ISO 787-13: Determination of water-soluble sulphates, chlorides, and nitrates
This suite delivers a full range of analytical approaches essential for characterizing pigments and fillers under standardized conditions.
Keywords: tamped volume determination, apparent density after tamping, pigment test methods, extender density measurement, measuring cylinder tamping, powder bulk density, pigment quality control, ISO 787-11, CEN standard for pigments, powder compaction testing.
