ISO 7906:2022

Overview

ISO 7906:2022 - Leather - Tests for colour fastness - General principles of testing defines the common principles, terminology and reporting practices used across leather colour fastness test methods. It provides a consistent framework for evaluating colour change and staining of leather, coated leather and related materials (including leather board), and for assessing the colour fastness of leather dyes applied to retanned or crust leather.

Keywords: ISO 7906:2022, leather colour fastness, colour fastness testing, fastness ratings, adjacent fabrics, leather dyes.

Key topics and requirements

• Scope and purpose: Establishes general principles common to individual leather fastness methods (listed in Annex A), and clarifies uses and limitations.
• Terms and definitions: Uses ISO 15115 vocabulary to ensure consistent terminology.
• Principle and test structure: Defines standard clause headings for individual methods (Scope, Principle, Apparatus, Test specimen, Procedure, Test report).
• Apparatus, reagents and references:
  • Test solutions prepared with Grade 3 water (ISO 3696).
  • Concentrations specified in ml/l or g/l; qualities of chemicals specified in single methods.
• Adjacent materials:
  • Guidance on single-fibre and multifibre adjacent fabrics (types DW and TV per ISO 105-F10). Strips of at least 1.5 cm width for multifibre fabrics.
  • Suitable plastics (PVC, TPU, EVA) and metals (silver, copper, brass) may be specified; composition details must be reported.
• Specimen preparation & conditioning: Requirements for preparing leather specimens and composite specimens (staples, multifibre, etc.) and for conditioning prior to testing.
• Assessment & reporting:
  • Fastness ratings for change in colour and staining of adjacent materials.
  • Other visible changes (surface appearance, gloss, shrinkage) recorded separately.
  • Conditions for viewing and illumination when assessing results are specified.
• Test report: Mandatory descriptive information about materials, adjacent fabrics, coatings and any deviations.

Practical applications and users

ISO 7906:2022 is essential for:

• Leather manufacturers and tanneries validating colour stability during production and use.
• Quality-control laboratories performing standardized fastness tests.
• Dye and chemical suppliers assessing dye fastness on retanned or crust leather.
• Footwear, upholstery and automotive suppliers checking leather compatibility with linings, coatings and adjacent materials.
• R&D teams developing colour-fast leather finishes and coatings.

Benefits: consistent test design, comparable fastness ratings, clear reporting for regulatory compliance and product specifications.

Related standards

• ISO 3696 - Water for analytical laboratory use (Grade 3)
• ISO 15115 - Leather - Vocabulary
• ISO 105-F10 - Multifibre test fabric details (referenced for DW/TV types)

ISO 7906:2022 was prepared by IULTCS in collaboration with CEN/TC 289 and provides the baseline for all specific leather colour fastness test methods.