SIST EN ISO 1833-21:2019 PDF

Overview

SIST EN ISO 1833-21:2019 is an international standard developed by ISO and adopted by CEN, specifying a reliable quantitative chemical analysis method for textiles composed of complex fiber mixtures. This standard focuses on determining the mass percentage of chlorofibres, certain modacrylics, elastanes, acetates, and triacetates in blends with other fibers such as wool, silk, cotton, and synthetic fibers. The analysis employs cyclohexanone as the primary solvent to dissolve specific fibers selectively, enabling accurate measurement after removal of non-fibrous matter.

This method is critical to the textile industry for quality control, fiber content certification, and compliance with labeling regulations, offering consistent and reproducible results with a high precision level.

Key Topics

• Scope and Fibre Types: Applicable for mixtures containing chlorofibres, certain modacrylic fibers, elastanes, acetates, triacetates blended with wool, animal hair, silk, cotton, cupro, modal, viscose, lyocell, polyamide, acrylic, melamine, polyacrylate, and glass fibers.
• Method Principle: Dissolution of select fibers using cyclohexanone near its boiling point; residue is filtered, washed, dried, and weighed to calculate mass percentages.
• Apparatus Requirements: Includes specialized hot extraction equipment with reflux condenser, filter crucible, porous baffle, and heating device suited for cyclohexanone's boiling point (~156 °C).
• Procedure Highlights:
  • Use 100 ml cyclohexanone per gram of textile sample.
  • Hot extraction conducted for 60 minutes with controlled reflux cycles.
  • Washing with heated 50% ethanol and water without suction during wash phases.
  • Drying and weighing the remaining residue to determine fiber composition.
• Calculation and Precision: Results are calculated per ISO 1833-1 guidelines with corrected factors for certain fibers (e.g., silk, melamine, polyacrylate). Precision confidence limits are ±1 percentage point at 95% confidence.
• Safety: Cyclohexanone is flammable and toxic; proper precautions required during handling.

Applications

• Textile Quality Control: Enables manufacturers and quality inspectors to verify fiber composition in blended textiles, ensuring product consistency and customer transparency.
• Regulatory Compliance: Assists in meeting labeling laws and trade requirements by accurately quantifying fiber content in complex textile mixtures.
• Material Authentication: Useful in detecting fiber adulteration or verifying claims on textile products involving specialty fibers such as modacrylics, elastanes, and chlorofibres.
• Research and Development: Supports fiber blend optimization and innovation in performance textiles by providing precise compositional data.
• Industry Standardization: Serves as a harmonized method across European countries and beyond, facilitating international trade and quality benchmarking.

Related Standards

• ISO 1833-1: General principles of quantitative chemical analysis for textiles, providing overarching methodology for test execution and result interpretation.
• ISO 1833-13: Alternative test method for mixtures containing chlorofibres using carbon disulfide/acetone as solvents.
• ISO 1833-17: Focused on chlorofibre homopolymers analyzed with sulfuric acid for particular fiber blends.
• ISO 2076: Defines generic names of man-made fibres for standardized terminology.
• ISO 6938: Covers generic names and definitions for natural fibers, complementing analyses involving mixed fiber types.

By detailing a precise chemical analysis procedure using cyclohexanone, SIST EN ISO 1833-21:2019 ensures textile manufacturers and laboratories can reliably quantify specific fibers in complex blends. This supports transparency, quality assurance, and regulatory compliance in the global textile industry.