Overview
SIST EN ISO 14680-2:2006 is a European and international standard titled "Paints and varnishes - Determination of pigment content - Part 2: Ashing method (ISO 14680-2:2000)". This standard specifies a standardized procedure to measure the pigment content in paints and varnishes using the ashing method. It is part of a series of standards focused on testing and sampling of paints and varnishes, prepared by ISO/TC 35 and adopted by CEN. The ashing method involves removing binders and volatile components by heating to leave inorganic pigments and extenders for measurement.
Key Topics
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Scope and Applicability
SIST EN ISO 14680-2:2006 applies to paints and varnishes where pigment content needs to be determined accurately through ashing. It excludes materials containing aluminium, organic pigments, dyestuffs, or inorganic pigments treated with organics, which are partly lost during ashing. This method is generally unsuitable for UV paints or those with reactive diluents.
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Testing Principle
The method involves evaporating solvents, then ashing the residue at temperatures between 600 °C and 900 °C (or at 450 °C in the presence of carbonates). The remaining ash mass corresponds to the pigment content, including extenders and inorganic solids that are non-volatile at the test temperature.
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Apparatus Needed
- Porcelain crucibles
- Drying oven with controlled ventilation at 80±2 °C
- Muffle furnace or fast incinerator for ashing
- Analytical balance with 0.001 g precision
- Crucible tongs and desiccator
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Procedure Summary
- Heat crucible to constant mass and weigh.
- Add ~2 g of test paint, evaporate solvents at 80 °C.
- Ash the sample to remove organics, typically around 2 hours.
- Cool and weigh the crucible with ash residue until mass is stable.
- Calculate pigment content as a percentage of the original sample mass.
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Precision and Reliability
- Repeatability is ±2% between duplicate tests by the same operator/lab.
- Reproducibility is ±4% between different labs.
- Results differing by more than 0.5% relative to the mean require retesting.
Applications
SIST EN ISO 14680-2:2006 is invaluable for industries and laboratories involved in the quality control and formulation of paints, coatings, and varnishes. Accurate pigment content determination enables:
- Quality assurance of product consistency
- Regulatory compliance for pigment concentration limits
- Formulation development by quantifying pigment load
- Comparative analysis of raw materials and finished products
- Research and product innovation relating to coatings performance
It supports professionals in ensuring that paints and varnishes meet the required specifications for opacity, color strength, and durability relating to pigment levels.
Related Standards
This standard is part of the ISO 14680 series addressing pigment content measurement:
- ISO 14680-1: Centrifuge method for pigment content determination
- ISO 14680-3: Filtration method for pigment content determination
Additionally, sample preparation and testing reference the following international standards:
- ISO 1513: Examination and preparation of paint samples for testing
- ISO 15528: Sampling procedures for paints and varnishes
Together, these standards provide a comprehensive framework for sampling and assessing the pigment content in coating materials with different techniques suited to various product types.
By adhering to SIST EN ISO 14680-2:2006, testing laboratories and manufacturers can achieve precise, reproducible measurement of pigment content, critical for product quality and performance in the coatings industry.
