ISO 7211-6:2020

Overview

ISO 7211-6:2020 is an international standard established by the International Organization for Standardization (ISO) that provides standardized methods for the determination of the mass of warp and weft threads per unit area of woven textile fabrics. This measurement is performed after the removal of any non-fibrous matter present in the fabric. Precise assessment of warp and weft mass is critical for understanding fabric construction, quality control, and ensuring material specifications are met in textile manufacturing and testing.

This document updates the previous 1984 edition and is part of the broader ISO 7211 series, which covers methods for analyzing woven fabrics' construction. It serves as a key reference for laboratories, textile engineers, and quality assurance professionals involved in textile analysis.

Key Topics

• Scope and Purpose: Defines methods to determine the mass (grams per square meter) of warp and weft yarns after removing non-fibrous matter, helping to establish the composition and balance in woven fabrics.
• Methods Described:
  • Method A: Involves marking a fabric specimen, removing non-fibrous matter before dissection into warp and weft, followed by weighing.
  • Method B: Entails dissecting a known area specimen prior to removing non-fibrous matter, then weighing warp and weft separately.
• Required Apparatus:
  • Indelible marking ink
  • Scissors and dissection needles
  • Templates for cutting precise fabric specimens
  • Precision balance with 0.1% accuracy
• Sample Preparation:
  • Conditioning fabric under standard atmospheres as per ISO 139 to ensure equilibrium.
  • Careful marking and cutting to maintain thread integrity.
• Test Procedure:
  • Removal of non-fibrous materials using chemical or mechanical treatments compliant with ISO 1833-1.
  • Dissection of fabric samples into warp and weft threads carefully to avoid yarn loss.
  • Accurate weighing of threads to calculate mass per unit area.
• Calculation & Reporting:
  • Mass of warp, weft, and total fabric expressed in grams per square meter (g/m²).
  • Detailed test reports including testing atmosphere, method, and any deviations for traceability and quality assurance.

Applications

• Textile Quality Control: Ensuring fabric specifications meet required standards for warp and weft composition.
• Product Development: Assisting designers and engineers in evaluating fabric construction to optimize performance characteristics such as weight distribution, durability, and handfeel.
• Research and Testing Laboratories: Providing standardized protocols for consistent, reproducible measurements critical in textiles research.
• Compliance and Certification: Used by certification bodies to verify adherence to textile product standards.
• Material Characterization: Enabling textile manufacturers to better understand the structural properties of woven fabrics for improved manufacturing processes.

Related Standards

• ISO 139 - Textiles - Standard atmospheres for conditioning and testing to ensure consistent test environments.
• ISO 1833-1 - Textiles - Quantitative chemical analysis - Part 1: General principles of testing; related to removal of non-fibrous matter.
• ISO 3801 - Textiles - Woven fabrics - Determination of mass per unit length and mass per unit area, often referenced for overall fabric mass.
• Additional parts of the ISO 7211 series, covering various aspects of woven fabric construction analysis, complement this standard.

By following the guidelines in ISO 7211-6:2020, textile professionals can accurately determine the warp and weft mass distribution in woven fabrics, enabling precise fabric characterization which is essential for quality control, product development, and research in the textile sector. The use of this standard promotes uniform testing conditions and consistent results worldwide.