Overview
ISO 15701:2022 - Leather - Tests for colour fastness - Colour fastness to migration into polymeric material specifies a standardized laboratory method to assess the tendency of dyes and pigments to migrate from leather into an adjacent synthetic substrate. The procedure measures colour transfer from leather to a white polymeric sheet (commonly pigmented PVC) under controlled heat and pressure. The method applies to leather of all kinds at any stage of processing and supports consistent quality and compatibility testing between leather and polymeric components.
Key topics and technical requirements
- Test principle: Place the leather specimen face-down on a white polymeric sheet, subject the composite to heat under uniform pressure, then assess staining on the polymeric sheet.
- Specimen size and fixture: Typical specimen area is 30 × 20 mm (cut with a rectangular press knife). Composite specimens are held between inert plates (e.g., glass) under a constant pressure of (81.7 ± 4.0) kPa using an approximately 5 kg load.
- Temperature and time: Standard exposure is (50 ± 2) °C for 16 hours (alternate temperatures may be used for specific assessments).
- Polymeric sheet: Preferably white-pigmented, plasticized PVC, ~0.5 mm thick; Annex A describes composition and commercial sources for standard sheets.
- Finish condition: Test can be performed with the leather finish intact or intentionally broken (abrasion procedure described).
- Assessment: Staining is evaluated visually using the ISO 105-A03 grey scale or instrumentally per ISO 105-A04; hue shifts should be recorded where applicable.
- Precision and reporting: Visual precision is typically ±0.5 grey scale units. The test report must reference ISO 15701:2022 and include specimen description, surface tested, finish condition, test temperature, grey scale rating (and hue), polymeric material source, deviations and test date.
Applications and users
ISO 15701:2022 is used to:
- Validate compatibility of leather with synthetic parts in footwear, upholstery, garments, bags and automotive interiors.
- Support quality control in tanneries and leather finishing operations to prevent migration-related defects.
- Guide R&D for dye and pigment selection to minimize transfer to adjacent polymeric components.
- Provide evidence in supplier specifications, material acceptance, and dispute resolution between leather and polymer manufacturers.
Primary users include leather manufacturers, independent testing laboratories, footwear and furniture producers, automotive interior specifiers, product compliance teams and material scientists.
Related standards
- ISO 105‑A03 - Grey scale for assessing staining (visual)
- ISO 105‑A04 - Instrumental assessment of staining
- ISO 105‑A01 - Colour fastness testing principles
- ISO 2418 - Leather sampling location
- IULTCS/IUF test designation IUF 412
Keywords: ISO 15701:2022, colour fastness, leather testing, migration into polymeric material, PVC, grey scale, dye migration, leather quality control.