ISO 18451-1:2019

Overview

ISO 18451-1:2019 provides standardized terminology used in the field of pigments, dyestuffs and extenders. This Part 1 document delivers general terms and definitions to ensure consistent communication across formulation, testing, manufacturing and regulatory activities. Where relevant, it cross-references ISO 4618 for colourant terminology related to coating materials.

The second edition incorporates editorial updates and alignment with related ISO documents, including updated definitions for colour difference and extenders, and new entries for nanomaterial-related terms.

Key Topics

The standard covers a comprehensive set of concepts and practical terms used across the colourant industry. Key topics include:

• Colourant taxonomy: distinction between pigments (insoluble) and dyestuffs (soluble).
• Colour properties: colour, chroma, lightness and colour difference (ΔE*) with references to CIELAB/CIELUV spaces.
• Pigment types: examples such as aluminium pigment, carbon black, bismuth vanadate and chromium oxide pigments.
• Extenders and fillers: definition and notes on industry usage (extender vs filler), plus functional extenders.
• Dispersion and application: dispersibility, dispersing, fineness of grind, final level of dispersion and related processing terms.
• Surface and performance terms: bleeding, blooming, chalking, hiding power and fastness.
• Advanced topics: inclusion of nanomaterial, engineered/manufactured/incidental nanomaterial and nanoextender definitions.

These topics are organized to support practical interpretation in laboratories, production lines and product specifications.

Applications

ISO 18451-1:2019 is directly useful for professionals and organizations that require clear, harmonized terminology:

• Formulation chemists and R&D teams ensuring consistent specification of colourants and extenders.
• Quality control and analytical laboratories defining test methods, reporting colour differences and dispersion metrics.
• Coatings, plastics and rubber manufacturers aligning product data sheets, safety data and technical documentation.
• Regulatory and procurement teams relying on uniform terms for compliance, tendering and international trade.

Benefits include reduced ambiguity in specifications, improved reproducibility of tests and clearer cross-industry communication.

Related Standards

Relevant cross-references that appear in or complement ISO 18451-1:2019:

• ISO 4618 (colourants in coating materials)
• ISO 11664 series (CIELAB/CIELUV colour spaces)
• ISO 18314-4 (colour difference alignment)
• ISO 3262-1 and ISO 787-25 (extender and shade definitions)
• DIN 6176 (industrial colour difference formula)

Adopting ISO 18451-1:2019 terminology supports consistent, high-quality documentation and clearer technical exchange across pigments, dyestuffs and extenders supply chains.