GB/T 3903.26-2020

Footwear—Test methods for stiffeners and toepuffs—Bondability (English Version)

Standard No.

GB/T 3903.26-2020

Language

Chinese, Available in English version

Release Date

2020

Published By

General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China

Latest

GB/T 3903.26-2020

Replace

GB/T 3903.26-2008

Scope

This standard specifies the test method for determining the adhesive performance of the main heel and toe cap of hot-melt and solvent-based materials to upper and lining materials. This standard applies to main heels and toe caps for shoes.

Introduction

Analysis of the key points of standard revision

Technical parameters	2008 edition	2020 edition	Significance of revision
Leather reference	Unspecified technical indicators	Citing L1 material specifications in CEN/TR15990	Improving test comparability
Pressure control	2.5kg/cm2	245kPa±5kPa	Standardization of SI units
Results	Intermediate tensile force	Average tensile force	More scientific data

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Core test methods

1. Hot melt material test

The step temperature test method (70℃~150℃) was adopted, and the pressing device was maintained at 245kPa pressure for 10 seconds to form a leather-sample-non-woven fabric three-layer structure specimen.

2. Solvent-based material test

After acetone activation, the test was pressurized at 50℃, focusing on the adhesive strength after the solvent evaporated.

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Key technical requirements

Equipment precision control

The tensile testing machine must meet ISO7500-1 second-level precision (error <2%), and the clamp speed must be strictly controlled at 100±10mm/min.

Environmental adjustment

All samples must be subjected to 24-hour environmental balance in accordance with ISO18454 standards, and the temperature and humidity must be controlled at 23±2℃, 50±5%RH.

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Implementation recommendations

1. Establish a regular verification system for leather reference materials to ensure that their physical properties meet the requirements of Appendix NA
2. It is recommended to add two test temperature points of 90℃ and 130℃ for multiple batches of samples
3. Pay attention to controlling the immersion time within 6±0.5 hours

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Standard Evolution Analysis

This standard is equivalent to ISO20863:2018, and compared with the 2008 version, it mainly strengthens: ① the standardization of test materials ② the scientific nature of data collection ③ the coordination with EU standards. The newly added solvent-based material test method fills the gap in industry testing.

GB/T 3903.26-2020 Referenced Document

• ISO 7500-1 Metallic materials - Calibration and verification of static uniaxial testing machines - Part 1: Tension/compression testing machines - Calibration and verification of the force-measuring system

GB/T 3903.26-2020 history

• 2020 GB/T 3903.26-2020 Footwear—Test methods for stiffeners and toepuffs—Bondability
• 2008 GB/T 3903.26-2008 Footwear.Test methods for stiffeners and toepuffs.Bondability

GB/T 3903.26-2020 -All Parts