Overview
ISO 20869:2010 specifies a standardized laboratory test method for determining water soluble content in footwear components - specifically outsoles, insoles, linings and insocks. The method quantifies total water-soluble substances, separates inorganic (sulfated ash) and organic fractions, and expresses results as percentages on a fat‑free conditioned sample basis. It is a technical reference for material characterization and quality control in footwear manufacturing and testing.
Key topics and technical requirements
- Scope: Determination of water soluble matter from footwear components (outsoles, insoles, linings, insocks).
- Sampling & conditioning: Test specimens taken per ISO 17709; condition samples 24 h in standard atmosphere per ISO 18454.
- Sample preparation: Material ground and extracted with dichloromethane in a Soxhlet apparatus for a minimum of 30 refluxes before testing.
- Test procedure (summary):
- Shake 10 g of conditioned, DCM‑extracted material with 500 ml distilled water at (23 ± 2) °C, mechanically at (50 ± 10) rpm for 2 h.
- Filter through a 185 mm fluted filter, discard first 50 ml of filtrate, use subsequent 50 ml aliquots for analysis.
- Evaporate 50 ml filtrate to dryness, dry at (102 ± 2) °C, cool in desiccator and weigh to obtain total water solubles.
- Determine sulfated ash (water soluble inorganic substances) by treating the residue with 1 mol/l sulfuric acid, fuming, then igniting in a muffle oven at (690 ± 10) °C.
- Water soluble organic substances = total water solubles − sulfated ash.
- Apparatus & reagents: Wide‑neck flasks, fluted filters, precise balances (0.1 mg sensitivity), shaker (50 ±10 rpm), ovens, water bath, muffle furnace, distilled water, 1 mol/l H2SO4, etc.
- Expression of results: Results reported as percent (to one decimal place), average of two test pieces; reporting must reference ISO 20869:2010 and include sample identification and date.
Applications and who uses it
- Footwear manufacturers for quality control of components and materials.
- Independent testing laboratories performing material characterization and conformity testing.
- R&D teams evaluating material formulations or changes in adhesives, fillings or linings that affect water‑soluble extractables.
- Procurement and compliance professionals requiring documented test results for supplier qualification.
Practical benefits include consistent lab-to-lab comparability, identification of high water‑soluble content that may affect durability, and support for material selection decisions.
Related standards
- ISO 17709 - Footwear: sampling location, preparation and conditioning of samples.
- ISO 18454 - Footwear: standard atmospheres for conditioning and testing.
Keywords: ISO 20869, water soluble content, footwear testing, outsoles, insoles, linings, insocks, sulfated ash, water soluble inorganic, water soluble organic, test method.