Overview
EN ISO 17694:2016 (ISO 17694:2016) specifies a standardized laboratory method to determine the flex resistance of footwear uppers and linings, irrespective of material. The test simulates damage caused by inward folding of the vamp (forepart) and assesses material durability for the intended end use. This European adoption by CEN supersedes EN 13512:2001 and aligns with ISO footwear test practice.
Key topics and technical requirements
- Scope: Measures resistance to cracking or failure at flexing creases for uppers and linings.
- Test specimens: Rectangular pieces cut from the vamp or sheet material. Typical cutter size references: press knife ~70 × 45 mm; specimen length must remain (70 ± 1) mm.
- Orientation: Half specimens cut along the material direction and half perpendicular (backbone/warp/machine directions).
- Flexing machine requirements: Based on ISO 5402-1 (flexometer method):
- Oscillation angle of the upper clamp: 22°30′ ± 0°30′.
- Oscillation speed: 100 ± 5 cycles/min.
- Distance between clamps (upper horizontal position): 25 ± 1 mm.
- At least four pairs of clamps and means to count cycles.
- Conditioning modes: Tests may be performed dry, wet, or cold:
- Dry: specimens conditioned in a standard atmosphere per ISO 18454 for ≥24 h.
- Wet: specimens water-saturated using distilled/deionised water (ISO 3696 Grade 3) and vacuum submersion (
