Overview - ISO 9073-8:1995 (Textiles - Nonwovens - Liquid strike-through time)
ISO 9073-8:1995 specifies a laboratory method for measuring the liquid strike-through time of nonwoven coverstocks using simulated urine. The procedure times how long a defined volume of simulated urine takes to pass through a nonwoven sample into a reference absorbent pad. The method is intended for comparative testing of nonwoven materials and does not simulate in-use conditions for finished products (e.g., diapers or pads).
Key topics and technical requirements
- Test principle: A measured volume (5.0 ml) of simulated urine is discharged onto a nonwoven test piece; electronic timing starts when liquid bridges electrodes and stops when penetration is complete.
- Simulated urine: 9 g/l sodium chloride solution in Grade 3 water (ISO 3696) with a surface tension of 70 ± 2 mN/m. Surface tension must be checked before each series; any surfactant addition must be reported.
- Reference absorbent pad: Five layers of filter paper (100 mm × 100 mm) with a specified strike-through benchmark (mean ~3 ± 0.5 s in 10 determinations).
- Apparatus: 50 ml burette, funnel with magnetic valve (discharge characteristics specified), strike-through plate with corrosion‑resistant electrodes (1.6 mm platinum or stainless wire), transparent baseplate (~125 × 125 × 5 mm), and an electronic timer readable to 0.01 s.
- Samples & conditioning: Cut 10 test pieces (125 mm × 125 mm recommended) and condition them per ISO 139 standard atmospheres.
- Results reporting: Individual strike-through times, mean time, coefficient of variation, conditioning atmosphere, any deviations (e.g., surfactant use).
Practical applications and users
ISO 9073-8 is used to:
- Compare liquid penetration performance of nonwoven coverstocks in product development and material selection.
- Support quality control and batch-to-batch consistency checks for nonwoven manufacturers.
- Provide standardized data for R&D teams optimizing liquid-handling surfaces in hygiene products (e.g., diaper topsheets, medical pads).
- Supply test laboratories with a reproducible method for reporting strike-through times.
Primary users:
- Nonwoven fabric manufacturers
- Personal hygiene and medical absorbent product developers
- Accredited testing laboratories and quality assurance teams
- Procurement and specification engineers assessing coverstock performance
Related standards
- ISO 9073 (series) - Test methods for nonwovens (other parts: mass, thickness, tensile, tear, drape, etc.)
- ISO 139 - Standard atmospheres for conditioning and testing
- ISO 186 - Sampling to determine average quality
- ISO 3696 - Water for analytical laboratory use
Keywords: ISO 9073-8, nonwovens test methods, liquid strike-through time, simulated urine, nonwoven coverstock, absorbent pad testing, textile testing, hygiene product development.