Overview
EN ISO 105-N04:1995 is an international standard established by CEN for evaluating the colour fastness of natural cellulose textiles to severe bleaching using sodium chlorite. This test method is essential for the textile industry to ensure that fabrics retain their colour quality and resist damage during textile processing involving bleaching agents. It provides a reliable procedure to assess both colour change on tested specimens and staining on adjacent fabrics using standardized grey scales.
Key Topics
- Test Scope: This standard specifies a procedure to determine the resistance of natural cellulose textiles to severe bleaching with sodium chlorite, commonly used in textile processing.
- Test Method: The textile specimen is placed in contact with one or two specified adjacent fabrics and treated in a sodium chlorite bleaching solution at controlled temperature and pH. The specimen is then rinsed and dried before assessment.
- Assessment Criteria: Colour changes on the specimen and staining of the adjacent fabrics are evaluated via ISO grey scales for colour change and staining, ensuring objective and comparable results.
- Test Conditions: The sodium chlorite solution is carefully prepared to 2.5 g/l concentration with pH adjusted to 3.5 using formic acid. The test is conducted at 80 °C for one hour without agitation to simulate severe bleaching conditions.
- Specimen Preparation: Fabric specimens measuring 40 mm x 100 mm are sewn to the multi-fibre or single-fibre adjacent fabrics as per specified configurations to study colour migration and durability.
- Reporting: Detailed recording of test results includes numerical ratings for colour change and staining along with the identification of sample types and test conditions.
Applications
- Textile Quality Control: Manufacturers use EN ISO 105-N04 to verify the colour fastness performance of cellulose-based textiles, ensuring resistance to bleaching and safeguarding product quality.
- Product Development: Textile chemists apply this standard during formulation of dyeing and bleaching processes to optimize colour durability under harsh chemical treatments.
- Consumer Safety and Expectations: Assures consumers that textiles will maintain colour integrity and avoid unwanted staining when subjected to bleaching in cleaning or manufacturing environments.
- Compliance Verification: Helps businesses meet regulatory and market standards related to textile colour fastness and durability.
Related Standards
- ISO 105-A01:1989 - General principles of colour fastness testing for textiles
- ISO 105-A02:1993 - Grey scale for assessing change in colour
- ISO 105-A03:1993 - Grey scale for assessing staining on adjacent fabrics
- ISO 105-F:1985 - Standard adjacent fabrics used in colour fastness tests
- ISO 105-F10:1989 - Specifications for multifibre adjacent fabric for testing
Keywords: colour fastness to bleaching, sodium chlorite test, cellulose textiles, textile colour durability, textile bleaching resistance, ISO 105-N04, textile testing standard, grey scale assessment, textile quality control.