Overview
EN ISO 17231:2017 - Leather - Determination of water repellency of garment leather (ISO 17231:2017) specifies a standardized spray test to assess the surface wetting (water repellency) of leathers intended for clothing. Prepared by IULTCS/IUP and adopted by CEN, the method measures how much of the leather surface becomes wetted when a controlled volume of distilled/deionized water is sprayed onto a mounted test piece. Importantly, the standard does not measure resistance to water penetration through the leather.
Key topics and technical requirements
- Scope: Applicable to all garment leathers for assessing surface wetting (spray repellency), not penetration resistance.
- Test principle: A fixed volume of water is sprayed onto a test piece mounted at a 45° angle; the wetting appearance is compared to descriptive/photographic standards and water uptake is measured gravimetrically.
- Apparatus & conditions:
- Funnel diameter ≈ 150 mm; nozzle assembly with a metal spray nozzle having 19 holes (≈ 0.9 mm each).
- Test piece centre positioned 150 mm ± 2 mm below nozzle; specimen held at 45.0° ± 2.5°.
- Water volume: 250 ml ± 5 ml of distilled/deionized water (ISO 3696 Grade 3); flow duration ~27.5 s ± 2.5 s.
- Test piece size: three square samples, 182 mm ± 2 mm side; balance accuracy 0.001 g.
- Rating system:
- Spray rating scale 1–5 (ISO descriptive and photographic scale, Annex A).
- 1 = wetting of whole sprayed surface; ... 5 = no wetting and no adherence of drops.
- Results reported:
- Spray rating, mass of water absorbed (g), percentage water absorbed, conditioning atmosphere (per ISO 2419), and any deviations.
Applications and users
- Practical uses:
- Quality control for garment leather manufacturers and tanners to monitor surface repellency after processing or finishing.
- Specification testing for buyers, brands, and technical teams evaluating leather performance for outerwear, jackets, gloves and fashion garments.
- R&D labs assessing finishing treatments (e.g., hydrophobic coatings) or comparing supplier lots.
- Who uses this standard:
- Leather technologists, laboratory technicians, quality assurance teams, product developers, and procurement/specification engineers in footwear/garment supply chains.
Related standards
This standard provides a repeatable, internationally recognized method for assessing leather surface wetting-essential for consistent product quality and formulation decisions in the leather and apparel industries.