ISO 9073-6:2025

Overview

ISO 9073-6:2025 - "Nonwovens - Test methods - Part 6: Absorption" defines standardized laboratory methods for assessing how nonwoven fabrics behave in contact with liquids. The standard covers three measurable aspects of absorbency: liquid absorbency time, liquid absorptive capacity (LAC) and liquid wicking rate (capillarity). Tests exclude fabrics that contain super‑absorbent materials.

Key topics and technical requirements

• Scope and conditioning

  • Sampling according to ISO 186 and conditioning per ISO 139 are required before testing. The test liquid must equilibrate with the conditioning atmosphere.

• Liquid absorbency time

  • Measures time for a rolled specimen to become completely wetted when dropped into liquid.
  • Typical specimen: five strips (76 ± 1 mm in machining direction) each ~5 ± 0.1 g.
  • Apparatus: cylindrical wire basket (80 ± 1 mm high, 50 ± 1 mm diameter, mass 3 ± 0.1 g, mesh ≈ 20 mm).
  • Drop height: 25 ± 1 mm from liquid surface. Results reported as average time and standard deviation.

• Liquid absorptive capacity (LAC)

  • Quantifies mass of liquid held per unit mass of fabric after immersion and drainage.
  • Typical specimen: five pieces 100 ± 1 mm × 100 ± 1 mm; use stacked piles if individual pieces < 1 g.
  • Apparatus: stainless‑steel wire gauze (2 mm nominal mesh per ISO 565), immersion depth ~20 mm.
  • Procedure highlights: 60 ± 1 s immersion, 120 ± 3 s vertical drainage, weigh to ±0.01 g accuracy.
  • LAC formula: LAC (%) = (mass_after − mass_before) / mass_before × 100. Report average and standard deviation.

• Liquid wicking rate (capillarity)

  • Defines how quickly liquid is transported into and along the fabric by capillary action.
  • The standard provides apparatus, specimen preparation, procedure, result expression and reporting requirements for wicking tests.

• Reporting

  • Test reports must reference ISO 9073-6:2025, identify specimens and liquid, state dimensions and results, note deviations, and use SI units (other units may be reported separately).

Applications and users

ISO 9073-6 is essential for:

• Nonwoven manufacturers (quality control and product development)
• R&D teams developing hygiene, medical, wiping, filtration, and comfort fabrics
• Test laboratories and certification bodies verifying liquid handling performance
• Procurement and specification writers who require reproducible absorption data

Practical use cases include comparing materials for diapers, wipes, surgical drapes, cleaning cloths, and any nonwoven product where liquid handling, speed of wetting or capillary transport affects performance.

Related standards

• ISO 9073 series (other nonwoven test methods)
• ISO 139 (conditioning)
• ISO 186 (sampling)
• ISO 565 (test sieves / gauze mesh)

Keywords: ISO 9073-6, nonwovens test methods, absorption test, liquid absorbency time, liquid absorptive capacity, liquid wicking rate, nonwoven fabrics testing, capillarity.