ISO 18314-1:2015

Overview

ISO 18314-1:2015 - Analytical colorimetry - Part 1: Practical colour measurement specifies a standardized method to determine the colour coordinates of paint films. It applies to paint films that appear uniformly one colour (monochromatic) and that form an opaque system over a non‑transparent substrate. The standard excludes luminescent, transparent, translucent, retroreflective and metallic paint films.

Keywords: ISO 18314-1, analytical colorimetry, practical colour measurement, paint film colour measurement, colourimetric method.

Key Topics and Requirements

• Scope and sample types: Intended for opaque, uniformly coloured paint films. Transparent/translucent, metallic and retroreflective coatings are outside scope.
• Sample preparation: Follow ISO 15528 (sampling), ISO 1513 (sample prep) and ISO 1514 (test panels). Film thickness for semi‑covering films should be determined per ISO 2808.
• Measurement conditions:
  • Illuminant: D65 (standard daylight) - other illuminants for metamerism tests.
  • Observer: 10°.
  • Colour space: CIELAB or DIN 99; use CIEDE2000 or DIN 99 for small ΔE corrections.
  • Temperature: maintain sample at (23 ± 2) °C for reversible thermochromic paints.
• Instrument calibration:
  • Use manufacturer‑supplied white and black standards traceable to national standards.
  • Calibrate in the same environmental conditions as the measurement; repeat white calibration during long runs or when environment varies.
  • Keep standards protected from light, dust and damage; replace damaged standards.
• Apparatus:
  • Prefer spectrophotometers with spectral coverage 400–700 nm, spectral step and bandwidth ≤ 20 nm (preferably 5–10 nm).
  • Trichromatic colorimeters may be used where metamerism detection is not required.
• Measurement geometry:
  • Choice affects results - common geometries include di:8° (captures total first‑surface reflection) and 45°:0° (measures 0° reflected component). Select geometry based on surface gloss, texture and the objective (visual correlation vs. pigment analysis).
• Repeatability and sampling: Use flat, scratch‑free, dust‑free specimens; take multiple readings and exclude outliers. Use the largest practical instrument aperture for better precision.

Applications - Who Uses This Standard

• Coatings and paint manufacturers for production and QC
• Color laboratories and quality assurance teams
• Automotive, industrial and architectural coatings R&D
• Suppliers of pigments and colorants for performance verification ISO 18314-1 supports consistent, traceable colour measurement workflows for colour matching, batch control and specification compliance.

Related Standards

• ISO 18314-2, ISO 18314-3 (other parts of Analytical colorimetry)
• ISO 11664 series (colorimetry: observer, illuminants, CIELAB, CIEDE2000)
• ISO 1513, ISO 1514, ISO 2808, ISO 15528
• CIE 15 (Colorimetry)

Keywords reiterated: paint film colour measurement, ISO 18314-1, color measurement, spectrophotometer, CIELAB, D65, coatings quality control.