ISO 6719:2010

Overview

ISO 6719:2010 - "Anodizing of aluminium and its alloys - Measurement of reflectance characteristics of aluminium surfaces using integrating-sphere instruments" - defines a standardized method to measure the luminous reflectance properties of anodized aluminium surfaces. The standard covers measurement of total reflectance, diffuse reflectance, specular reflectance (principal gloss), specularity, and diffuseness using integrating-sphere reflectometers. Note: the method is unsuitable for lighting reflectors.

Key topics and technical requirements

• Measurement principle: Use of an integrating-sphere reflectometer to collect and integrate reflected light flux from a specimen; photometric measurement simulates CIE standard illuminants and photopic response per ISO 11664-2.
• Apparatus geometry: Requirements for integrating-sphere construction and alignment (e.g., port area ≤ 5% of internal surface, entrance and specimen ports on same great circle, photometer at 90° ± 0.5°).
• Specular-included vs specular-excluded: Procedures for pivotable spheres or fixed-sphere types to obtain total (Qr) and diffuse (Qd) reflectance; typical specular measurement using 9° ± 1° incidence.
• Irradiation beam: Beam must be substantially unidirectional (rays within 3° of axis) and have specified annular dimensions to ensure accurate specular/diffuse separation.
• Calibration: Use of a white primary standard (pressed barium sulfate per ISO 7724-2), black-surface or light-trap zero standard, and a calibrated first-surface mirror as a working standard.
• Measurement protocol: Take three readings for each orientation (0°, 45°, 90° to rolling/extrusion direction) and average. Directionality and diffuseness calculations are specified with formulae in the standard.
• Reporting: Test report must reference ISO 6719, include instrument/manufacturer, preparation method, average total/specular/diffuse values, computed specularity/diffuseness and directionality, and test date.

Applications and practical value

• Quality control for anodized aluminium finishes (architectural panels, consumer goods, transport components).
• Characterization of surface gloss, specularity, and diffuseness in R&D and coating development.
• Acceptance testing for suppliers and contract specifications where surface reflectance properties affect appearance or performance.
• Correlating reflectance data with colorimetric and visual appearance control in manufacturing.

Who uses this standard

• Test laboratories and QA/QC teams in aluminium finishing plants
• Anodizing and coating manufacturers
• Materials scientists, product designers, and specifiers requiring reliable surface reflectance data
• Procurement and compliance engineers for appearance-sensitive products

Related standards

• ISO 7724-2 (colour measurement reference for barium sulfate primary standard)
• ISO 11664-2:2007 (CIE standard illuminants / colorimetry)