Overview
ISO 105-A04:1989 specifies an instrumental method for assessing the degree of staining of adjacent fabrics in colour‑fastness tests as an alternative to the visual method. The standard defines how to measure the colour change of an adjacent (multifibre) specimen after a fastness test and how to convert measured colour differences into a standardized staining‑scale rating (SSR). It is intended to provide objective, reproducible results for reporting staining in textile colour‑fastness testing.
Key topics and technical requirements
- Scope: Instrumental assessment of staining of adjacent fabrics in any fastness test (alternative to visual assessment).
- Instruments: Use a spectrometer or colorimeter capable of measuring the size of one stripe in a multifibre adjacent fabric and illuminating the specimen with light resembling CIE Standard Illuminant D65 (Illuminant C permitted as alternative).
- Specimen preparation: Mount the adjacent fabric that contacted the test fabric together with a reference specimen of the adjacent fabric (exposed in absence of the test fabric) on non‑optically‑brightened white card stock.
- Measurement geometry: Preferred viewing geometries include sphere (d/0) with specular included or 0°/45° (or 45°/0°); include the specular component if instrument permits.
- Colour units and observers: Calculations use CIELAB units, typically with the CIE 10° observer and illuminant D65, with CIE 2° observer / illuminant C allowed as alternative.
- Calculation and conversion: Measure colour of both specimens, compute CIELAB colour difference and lightness difference to two decimal places, then convert to a staining‑scale rating using the standard’s equations and lookup table to report SSR on a 1–5 scale.
- Test reporting: Include the instrumental staining‑scale rating and a reference to ISO 105‑A04 in the colour‑fastness test report.
Applications and users
ISO 105-A04:1989 is useful for:
- Textile test laboratories seeking objective, repeatable staining assessments.
- Quality control teams in textile and dye manufacturing to monitor staining in fastness tests (washing, rubbing, perspiration, etc.).
- Product development and R&D groups validating dye formulations or finishing processes for transfer/staining behavior.
- Certification bodies and standards organizations requiring comparable instrumental results across labs.
Benefits include improved inter‑laboratory consistency, reduced subjectivity versus visual assessment, and documented SSR values suitable for QC and compliance records.
Related standards
- ISO 105-F10:1989 - Specification for adjacent fabric: multifibre.
- ISO 105-J01:1989 - Measurement of colour and colour differences.
- Other parts of ISO 105 (see ISO 105-A01 for the list of parts) for complete colour‑fastness test procedures.