Overview
ISO 22195-6:2021 is an international standard that specifies a test method for identifying the index ingredient chemical derived from Punica granatum (pomegranate) used in coloured textiles. This standard is part 6 of the ISO 22195 series focusing on the determination of natural dye components in textiles. It applies to both natural fibres and man-made fibres dyed with punica extracts.
Developed by ISO Technical Committee ISO/TC 38 on Textiles, the method uses chromatographic analysis to detect punicalagin, the characteristic chemical marker for punica dye. The standard supports verification of natural dye claims often associated with environmental benefits, ensuring accurate identification of punica-dyed fabrics in the textile industry.
Key Topics
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Scope and Application
The standard applies to dyed textiles where Punica granatum extract is used as a natural colourant. It allows identification of the punicalagin compound in both natural and synthetic fibres.
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Test Methodology
The method involves preparing fabric samples and extracting dissolved colourant using trifluoroacetic acid. Extraction is performed via an ultrasonic bath followed by filtration. The solution is then analyzed with High-Performance Liquid Chromatography coupled with a Photo Diode Array detector (HPLC-PDA).
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Chemical Marker – Punicalagin
Punicalagin is identified by its retention time and absorbance spectrum (wavelength 260 nm) during chromatographic analysis. The detection confirms the presence of punica-derived dye in the textile sample.
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Reagents and Equipment
Analytical grade reagents such as trifluoroacetic acid, acetonitrile, and distilled water are used. Specialized apparatus includes ultrasonic water bath, HPLC systems with PDA detectors, and membrane filters ensuring precise preparation and analysis.
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Test Reporting
The standard details essential information to be included in reports: sample identification, chromatographic conditions, results, and any procedural deviations. This ensures consistent documentation for quality assurance and regulatory compliance.
Applications
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Textile Quality Assurance
ISO 22195-6:2021 assists textile manufacturers and testing laboratories in verifying whether fabrics were dyed with pomegranate-based natural dyes, supporting product authenticity claims.
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Environmental Impact Verification
As natural dyes are valued for their eco-friendly profiles, this method enables brands and certification bodies to substantiate environmental claims linked to natural dye usage.
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Research and Development
Researchers can apply the standard to study dye uptake on various fibre types or to develop new sustainable dyeing processes using punica extracts.
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Customs and Regulatory Compliance
Customs agencies and regulatory authorities can use this standard to validate import/export claims about textile composition and dyeing methods.
Related Standards
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ISO 22195 Series
A broader set of standards for determining various natural dye ingredients in coloured textiles beyond punica, covering other plant-based dyes.
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ISO 3696:2018
Specifies water quality requirements for laboratory use, referenced here for reagent preparation to ensure analytical accuracy.
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ISO/IEC Directives, Part 2
Provides editorial rules for preparing and maintaining ISO standards such as ISO 22195-6:2021.
By implementing ISO 22195-6:2021, textile professionals gain a scientifically validated approach for natural dye identification. This aids in maintaining transparency, quality, and ecological responsibility in the textile supply chain, aligning with growing consumer demand for sustainable and authentic textile products.