ISO 5403-2:2011

Overview

ISO 5403-2:2011 specifies a standardized method to determine the dynamic water resistance of flexible leather using repeated angular compression (Maeser). Applicable to all flexible leathers and particularly suited to footwear materials, the method uses a Maeser-type machine and offers both visual and optional electronic detection to record the number of flex cycles to first water penetration.

Key Topics

• Principle: A square specimen is folded, clamped in opposing V-shaped jaws to form a trough, immersed in water or an electrolyte, and subjected to repeated angular flexing until water penetration is observed.
• Apparatus highlights: Maeser-type machine with V-shaped clamps, pivoting movable clamp, means to apply harmonic motion at approximately 90 cycles/min, and a container to hold water/electrolyte. Electronic detection uses steel balls and a high-potential electrode to sense conductivity drop.
• Specimen preparation: Two square specimens (cut to at least 100 mm × 100 mm), marked for principal direction, conditioned per ISO 2419. Edges may be sealed and thin compressible strips used to avoid edge leakage.
• Detection options:
  • Visual inspection for damp patches or droplets at the fold.
  • Electronic detection: an electrolyte and electrode arrangement that stops the test when resistance falls below a specified threshold.
• Measurements and reporting: The primary result is the number of cycles to first penetration. Optional water absorption (percentage gain) can be determined by weighing before and after flexing.

Applications

• Quality control of leather for footwear, where dynamic flexing and surface integrity under moisture are critical.
• Comparative testing of finishes, coatings and finishing processes to understand how surface coats and microcracks affect water resistance.
• R&D to simulate repetitive folding wear and to evaluate treatments intended to improve water repellence.
• Production acceptance testing and supplier verification to ensure consistent material performance.

Practical advantages include reproducible, repeatable assessment of dynamic wet flex performance and an electronic option for automated endpoint detection. Pre-treatments such as light abrasion (specified in the standard) can be used to simulate wear and expose coatings that might crack in service.

Related Standards

• ISO 5403-1 - Repeated linear compression (penetrometer) method (same series).
• ISO 2418 - Sampling location for leather tests.
• ISO 2419 - Sample preparation and conditioning.
• ISO 3696 - Water quality for analytical use.
• ISO 5402-1 - Flex resistance (referenced for alternative flexing simulation).

For test reporting, include the standard reference (ISO 5403-2:2011), specimen description, conditioning details, detection method (visual or electronic), cycles to penetration, any pre-treatments and deviations from the procedure.