ISO 5403-1:2025

Overview

ISO 5403-1:2025 - Leather - Determination of water resistance of flexible leather - Part 1: Repeated linear compression (penetrometer) is an international test method for measuring the dynamic water resistance of flexible leathers using repeated linear compression. The second edition (2025) updates the 2011 edition and is particularly suited to leathers intended for footwear applications. The test records the time until water penetration as well as water absorption and water transmission through a flexed, partially immersed specimen.

Key Topics and Requirements

• Scope and principle: Measures water penetration under compression-type flexing (penetrometer), distinct from folding-type methods (ISO 5403-2).
• Apparatus: Test machine with a pair of horizontal cylinders (30.0 ± 0.5 mm diameter), motor producing a crank motion (≈50 cycles/min) and selectable amplitudes (1.0, 1.50, 2.0 or 3.0 mm); tank for distilled/deionized water; ring clamps; press knife; balance (0.001 g); timer; abrasive paper and absorbent cloth.
• Specimen preparation: Cut test pieces per ISO 2418, orient directions relative to backbone, lightly abrade or flex to simulate wear (abrasion protocol and optional pre-flexing referenced), and condition specimens per ISO 2419.
• Procedure:
  • Determine specimen stiffness using auxiliary apparatus to select test amplitude (compression % based on measured forces).
  • Measure penetration time while the specimen is compressed and partially immersed.
  • Measure water absorption (mass gain of specimen) and water transmission (mass gain of conditioned absorbent cloth) if required.
• Results and reporting: Express penetration time, percentage water absorption, and transmitted mass; include test conditions, specimen orientation, pre-treatments and apparatus settings.
• Normative references: ISO 2418, ISO 2419, ISO 3696, ISO 15115.

Applications and Who Uses It

• Footwear manufacturers: quality control of uppers, linings and flexible components to ensure water resistance under dynamic flexing.
• Leather tanneries and converters: product development, batch acceptance and process optimization.
• Testing laboratories and certification bodies: standardized method for comparative testing and compliance reporting.
• R&D teams and material specifiers: evaluate treatments, coatings and finishing impacts on dynamic water performance.
• Procurement and compliance: specify leather performance in contracts and technical specifications.

Related Standards

• ISO 5403-2 - Water resistance - folding-type flexing (complementary test method)
• ISO 2418 - Specimen position and preparation
• ISO 2419 - Conditioning of specimens
• ISO 3696 - Water for analytical laboratory use
• ISO 15115 - Leather vocabulary

For implementation and exact test parameters, consult the full ISO 5403-1:2025 document. This summary highlights practical uses and technical scope for professionals working with leather water-resistance testing.