Overview
ISO 22776:2004 - Footwear - Test methods for accessories: Touch and close fasteners - Shear strength before and after repeated closing - specifies a standardized laboratory procedure to determine the longitudinal shear strength of hook-and-loop (touch and close) fasteners used in footwear. The method measures maximum force per unit effective area required to separate mated tapes, both in a virgin state and after a defined number of opening/closing cycles.
Keywords: ISO 22776, touch and close fasteners, shear strength, footwear testing, hook and loop, repeated closing, test method.
Key topics and requirements
- Scope: Longitudinal shear strength of touch-and-close fasteners before and after repeated use.
- Specimens: Cut four 100 mm specimens from both hook and loop tapes; for cycling prepare 540 mm lengths that are later sectioned.
- Conditioning: Test specimens conditioned per EN 12222 standard atmosphere for a minimum of 24 h.
- Test assembly: Overlap length (Lo) depends on fastener type (e.g., 50 mm for woven hook + woven loop; 20 mm for many knitted/plastic combinations). Use the smaller measured effective width (We) for calculations.
- Shear test: Use a tensile testing machine compliant with EN ISO 7500-1; jaw separation rate = 100 mm/min ± 10 mm/min. Record maximum force (Fi) until separation or tensile failure.
- Cycling: Use a touch-and-close cycling machine with two drums (≈160 mm diameters), rotating the driven drum at 60 rev/min ± 5 rev/min for 5 000 revolutions, applying 1.0 N ± 0.1 N per mm of specimen width between drums.
- Equipment specifics: Roller device (≈100 mm diameter) for closing under standard pressure; alignment and uniform loading required.
- Calculations: Effective area Ae (cm2) = (Lo × We) / 100. Longitudinal shear strength S (N/cm2) = Fi / Ae. Report min, max and arithmetic mean over four combinations.
- Reporting: Include standard reference, full identification of tapes, overlap length, min/max/mean shear strengths (before and after cycling), failure modes, deviations, and test date.
Applications and users
This standard is used for:
- Footwear manufacturers and component suppliers to specify and verify fastener performance.
- Quality assurance and materials testing laboratories performing durability and safety testing.
- Product development and R&D teams assessing fastening systems for consumer or industrial footwear.
- Compliance and procurement teams ensuring consistent supplier specifications and acceptance criteria.
Practical benefits include standardized comparison of fastener durability, objective pass/fail criteria, and documented test data for product claims.
Related standards
- EN 12222 - Standard atmospheres for conditioning and testing of footwear and components
- EN 12240 - Determination of overall and effective widths of tapes
- EN ISO 7500-1 / ISO 7500-1 - Verification and calibration of force-measuring systems for tensile testing machines
ISO 22776 was prepared under ISO/TC 216 (Footwear) in cooperation with CEN, ensuring alignment with European test practice.