ISO 1833-2:2020

Overview

ISO 1833-2:2020 - Textiles: Quantitative chemical analysis - Part 2: Ternary fibre mixtures defines laboratory methods for determining the composition of textile samples that contain three fibre types (ternary mixtures). The standard describes the principle of selective solution and related procedures to quantify each fibre component by mass, expressed on a clean dry mass basis with agreed moisture regain and correction factors applied for losses during pre-treatment and analysis. It also applies to more complex mixtures when combinations of methods reduce the problem to simple cases.

Key topics and technical requirements

• Principle: Identification of components, removal of non-fibrous matter, then application of selective dissolution or manual separation to isolate components.
• Four analytical variants for ternary mixtures:
  • Variant 1: Dissolve component (a) from specimen 1 and component (b) from specimen 2; calculate the third by difference.
  • Variant 2: Dissolve (a) from specimen 1 (leaving b+c) and dissolve (a+b) from specimen 2 (leaving c).
  • Variant 3: Dissolve (a+b) from specimen 1 and (b+c) from specimen 2; determine b by difference.
  • Variant 4: Successive treatment of a single specimen (requires correction factors for mass losses from successive solvents).
• Pre-treatment and conditioning: Follow general principles in ISO 1833-1, including removal of non-fibrous matter and controlled testing atmosphere.
• Calculations and reporting:
  • Express component masses as percentages of total fibre mass.
  • Apply agreed moisture regain and correction factors for mass losses during chemical treatments.
  • Detailed formulae and worked examples are provided (Annex A).
• Combination methods: Manual separation combined with chemical analysis is permitted to simplify mixtures with more than three fibres.
• Documentation: Test report requirements and method precision are specified.

Practical applications

• Routine textile composition analysis in quality control laboratories.
• Material verification for manufacturers and converters to confirm fibre blends.
• Regulatory compliance, labelling and trade inspections where accurate fibre content is required.
• Research and development in fibre blending, recycling, and product performance studies.
• Useful when validating alternative analytical approaches and comparing results across laboratories.

Who uses this standard

• Textile testing laboratories and certification bodies
• Textile and apparel manufacturers and quality engineers
• Customs, regulatory and consumer protection agencies
• Academic and industrial researchers in textile science

Related standards

• ISO 1833-1:2020 - General principles of testing (normative reference)
• Other parts of the ISO 1833 series, which provide specific methods for binary mixtures and list applicable solvents, correction factors and typical combinations (see Annex B of ISO 1833-2:2020 for mapping of ternary cases).

Keywords: ISO 1833-2:2020, ternary fibre mixtures, quantitative chemical analysis, textiles, selective solution, fibre composition analysis, clean dry mass, moisture regain.