ISO 5402-1:2022

Overview

ISO 5402-1:2022 - Leather: Determination of flex resistance - Part 1: Flexometer method specifies a standardized laboratory procedure to measure the dry and wet flex resistance of leather and leather finishes. The method applies to all flexible leathers under 3.0 mm thickness and uses a reciprocating flexometer apparatus to produce a running fold while counting flex cycles and inspecting for damage.

Key topics and technical requirements

• Scope and purpose: Determines how many flex cycles a leather sample withstands without visible damage; used to define performance criteria for end uses.
• Apparatus: A flexometer with a movable upper clamp and fixed lower clamp, plus a counter. Key parameters:
  • Upper-clamp reciprocation angle 22.5 ± 0.5° at 100 ± 5 cycles/min.
  • Two permitted upper-clamp geometries (Specification 1 and 2); clamp type and manufacturer must be reported.
  • Vertical distance between upper-clamp ledge and lower-clamp edge 25.0 ± 0.5 mm.
• Sample prep and conditioning:
  • Sampling per ISO 2418; specimen preparation and atmospheric conditioning per ISO 2419.
  • Wet testing requires immersion using distilled/deionized water (ISO 3696 grade 3) in a desiccator with vacuum cycles to