Overview
EN ISO 105-Z09:1997 is an international standard developed by the Comité Européen de Normalisation (CEN) in collaboration with the International Organization for Standardization (ISO). It specifies a standardized method for determining the cold water solubility of water-soluble dyes in textiles at 25 °C. This test is crucial for assessing the behavior of colored textiles when exposed to cold water without prior heating, addressing important aspects of color fastness and dye stability in textile manufacturing and quality control. This method measures solubility visually and by flow-through time but does not assess absolute solubility.
Key Topics
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Scope and Purpose
The standard describes a procedure to determine the solubility limit of water-soluble dyes at a fixed temperature of 25 °C under controlled conditions without pre-heating. It is primarily used to evaluate the solubility threshold of dyes for quality assurance in textiles.
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Test Principle
Known concentrations of the dye are prepared in aqueous solutions and filtered at 25 °C using a thermostatically controlled glass Nutsch filter. The presence of residues on the filter after drying indicates exceeded solubility. The test uses visual inspection together with measurement of filtrate flow-through times as criteria.
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Equipment and Setup
- Glass beakers (400 ml capacity)
- Heating bath controlled to 25 ± 2 °C with magnetic stirrer
- Heatable Nutsch filter or Büchner funnel with vacuum apparatus
- Filter papers (70 mm diameter) with specific permeability characteristics
- Stopwatch for recording flow-through time
- Water complying with ISO 3696 grade 3 for analytical use
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Procedure Highlights
- Dye solutions of increasing concentration are stirred in water at 25 °C
- Solutions are filtered under vacuum without temperature shock
- Filter residues and filtration time indicate solubility limits
- The method includes a detailed reporting framework covering dye identification, filter type, stirring time, solubility limits, and any deviations or observations.
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Results Interpretation
The cold water solubility limit corresponds to the dye concentration at which filter residues become visible. A sharp increase in filtration time further confirms this solubility threshold.
Applications
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Textile Quality Control
Ensures dyes used in textile production are suitable for cold water laundering conditions and maintains color fastness.
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Dye Manufacturer Compliance
Supports manufacturers in validating and certifying dye solubility characteristics in product specifications.
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Research and Development
Used in developing new water-soluble dyes with targeted solubility profiles to optimize performance and environmental impact.
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Environmental Testing
Evaluates potential dye release into cold water effluents during textile washing, aiding environmental compliance efforts.
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Standardized Laboratory Testing
Provides replicable testing methods for textile laboratories to compare products reliably across regions.
Related Standards
- ISO 105-A01 – General information and list of parts for textile color fastness tests including solubility methods.
- ISO 3696 – Specifies water quality requirements for laboratory use, ensuring consistent solvent purity in testing.
- ISO 3819 – Defines laboratory beakers for preparing dye solutions.
- ISO 1773 – Covers specifications for laboratory glassware such as boiling flasks used in dye preparation.
Keywords: EN ISO 105-Z09:1997, water-soluble dyes, cold water solubility, textile dye testing, color fastness, Nutsch filter method, dye solubility limit, textile quality control, aqueous dye solutions, filtration test, standard test method, textile standards.