Overview
EN ISO 11641:2025 - Leather - Tests for colour fastness - Colour fastness to perspiration (ISO 11641:2025) specifies a laboratory method to assess how leather retains colour when exposed to human perspiration conditions. Adopted by CEN and prepared by IULTCS in collaboration with CEN/TC 289, this standard applies to leather at all processing stages and is particularly relevant for gloving, clothing, lining leathers and uppers of unlined shoes. The method simulates the more demanding alkaline perspiration environment to provide conservative, reproducible results.
Key topics and technical requirements
- Scope: Applies to all kinds of leather; can test finished leather intact or with the finish broken.
- Principle: Leather and adjacent fabric are soaked in an alkaline artificial perspiration solution and pressed together under controlled pressure and temperature; afterwards colour change and staining are assessed.
- Artificial perspiration composition: Per litre - 5.0 g sodium chloride (NaCl), 5.0 g tris(hydroxymethyl)aminomethane (tris), 0.5 g urea, 0.5 g nitrilotriacetic acid; pH adjusted to 8.0 ± 0.1 with 2 mol/L HCl.
- Test conditions: Uniform pressure of 12.5 ± 1.0 kPa applied using a rectangular weight-piece (approx. 5 kg, ~115 mm × 60 mm cross-section) between inert plates; oven drying at 37 °C ± 2 °C.
- Adjacent fabrics: Use multifibre (ISO 105-F10) or specified single-fibre adjacent fabrics (ISO 105-F01–F07) to assess staining.
- Evaluation: Change in colour and staining judged using grey scales (ISO 105-A02/A03) or instrumental methods (ISO 105-A04/A05).
- Supporting requirements: Specimen preparation (ISO 2418), general fastness test principles (ISO 7906), and laboratory water quality (ISO 3696).
Applications
- Routine quality control for tanneries and leather processors to ensure consistent dye stability.
- Product development and material selection for footwear, gloves, apparel, and linings where perspiration contact is expected.
- Supplier verification and acceptance testing in procurement contracts and technical specifications.
- Failure analysis and corrective action when customer complaints involve staining or colour change from sweating.
Who uses this standard
- Leather manufacturers and tanneries
- Footwear, glove and leather-goods designers and OEMs
- Independent testing and accreditation laboratories
- Quality assurance, compliance and purchasing departments
Related standards (if applicable)
- ISO 105-E04 (textile perspiration test)
- ISO 7906 (general principles of colour fastness testing)
- ISO 2418 (specimen preparation)
- ISO 105-A02/A03/A04/A05 (grey scales and instrumental assessment)
- ISO 105-F01–F10 (adjacent fabrics)
- ISO 3696 (laboratory water quality)
Keywords: EN ISO 11641:2025, colour fastness to perspiration, leather testing, artificial perspiration solution, grey scale, adjacent fabric, leather quality control.
