Overview
EN ISO 105-Z02:1995 is an international standard developed by CEN that specifies a method for testing the colour fastness of textiles to metals in the dyebath, specifically focusing on iron and copper. These metals can be present in dyeing processes due to their use in dyeing machinery or the water and steam involved. The standard assesses the impact these metal salts have on the colour stability of dyed textiles by comparing dyeings made with and without metal salts, using a grey scale for evaluation.
This test is critical in ensuring the durability and consistency of textile colours, helping manufacturers identify potential issues caused by metal contamination during dyeing. It supports quality assurance for textiles exposed to iron and copper in the production environment.
Key Topics
- Colour fastness testing: Measures fabric resistance to colour change in the presence of metal ions.
- Metals in dyebath: Focused on iron (ammonium iron(III) sulfate) and copper (copper(II) sulfate) salts that may affect dye stability.
- Test principle: Comparison of dyeings done with and without metal salts in the dyebath.
- Materials used:
- Undyed light wool fabric as test specimen.
- Standard dye-baths with added metal salt solutions.
- Grey scale for assessing colour change as per ISO 105-A02.
- Test procedure:
- Dye three fabric samples: one without metal salts, one with copper(II) sulfate, one with ammonium iron(III) sulfate.
- Maintain a consistent liquor ratio, typically 40:1.
- Assess and rate colour differences using the grey scale.
- Reporting: Includes dye specifics, method, and numerical ratings for colour change to document fastness levels.
Applications
EN ISO 105-Z02:1995 is especially valuable in the textile industry for:
- Quality control in textile manufacturing to monitor the influence of metal contaminants on dye stability.
- Research and development for improving dye formulations and machinery materials to enhance colour fastness.
- Ensuring compliance with customer and regulatory requirements for durable and colour-consistent textiles.
- Testing textiles destined for uses where exposure to metal ions is likely, such as in industrial washing, steam treatments, or water with high metal content.
- Assisting dyehouse operators in assessing the performance of dye processes and mitigating undesirable colour changes caused by iron or copper residues.
Related Standards
- ISO 105-A01:1989 - General principles of testing for colour fastness in textiles.
- ISO 105-A02:1993 - Grey scale for assessing change in colour; essential for evaluating test results in EN ISO 105-Z02.
- Other parts of the ISO 105 series covering a broad range of colour fastness properties such as to light, washing, rubbing, and perspiration.
Keywords: colour fastness test, textiles, dyebath metals, iron, copper, ISO 105-Z02, textile colour durability, dyeing process, metal contamination, wool fabric colour testing, grey scale assessment