Overview
ISO 105-B08:1995 - Textiles - Tests for colour fastness - Part B08 - defines a method for quality control of blue wool reference materials 1 to 7 used in ISO colour‑fastness-to‑light tests. The standard specifies instrumental and visual procedures to verify batch-to-batch consistency of dyed wool reference strips that serve as calibration/benchmark materials in light‑fastness testing.
Key topics and requirements
- Purpose: Confirm that production batches of blue wool reference materials (1–7) match the performance of a chosen reference standard before use in ISO 105-B light fastness tests.
- Measurement methods:
- Spectrophotometric evaluation of dye uniformity and of degradation, measuring reflection in the visible range (400–700 nm).
- Visual assessment of photodegradation using the grey scale for change in colour (ISO 105-A02) by experienced observers in a daylight‑type booth.
- Xenon‑arc exposure mounting and exposure procedure following the conditions in ISO 105-B02 to reach target contrasts (grey scale degree 4, then degree 3).
- Instrument settings and calculations:
- Use illuminant D and 10° observer where possible; include specular component and UV option if available.
- Calculate colour differences with the CMC formula: CMC 2:1 for dye regularity and CMC 1:1 for degradation comparisons (see ISO 105-J03).
- Sampling and mounting:
- Prepare three specimens (top, middle, bottom of a piece), ~300 mm long across full width, measure three positions (center, 150 mm from left, 150 mm from right) and multiple rotations per reading.
- Mount specimens above and below the reference on the exposure card with opaque masking for staged exposure.
- Acceptance criteria (informative annex A):
- Dye uniformity ΔE (CMC 2:1) generally should not exceed 0.5.
- Visual grey‑scale ratings should match the reference; differences >0.5 grey‑scale degree are judged unacceptable.
- Spectrophotometric degradation comparisons over 0.5 ΔE (CMC 1:1) are flagged unacceptable.
- Storage guidance (informative annex B): store references cool, dry, dark, and free of chemical vapours.
Applications and users
- Textile testing laboratories performing colour fastness to light measurements.
- Reference material manufacturers and quality control units producing blue wool reference strips.
- Dye manufacturers and textile mills that need validated reference materials for internal or outsourced light‑fastness testing.
- Standards bodies and accreditation assessors verifying conformity of test materials.
Related standards
- ISO 105-B02:1994 (Xenon‑arc light exposure method)
- ISO 105-A01:1994 (General principles for colour‑fastness tests)
- ISO 105-A02:1993 (Grey scale for evaluation of change in colour)
- ISO 105-J03:1995 (Calculation of colour differences)
Keywords: ISO 105-B08:1995, blue wool reference materials, color fastness to light, quality control, spectrophotometer, xenon arc, dyed wool, textile testing.