Automotive Interior Color Measurement with Spectrophotometers

The automotive industry demands perfection in every aspect of vehicle manufacturing, and interior components are no exception. Color consistency and accuracy in automotive interiors, be it dashboards, seats, trims, or panels, are critical for achieving a cohesive look. Any color variations can disrupt the aesthetic harmony of the interior and ultimately affect the customer’s perception of quality. However, maintaining color uniformity across diverse materials, finishes, and production batches is challenging. To overcome this challenge, manufacturers must implement strict color management practices and rely on advanced color measurement instruments like spectrophotometers.

Spectrophotometer Selection for Precise Automotive Interior Color Measurement

Spectrophotometers are indispensable instruments for measuring and maintaining color consistency. However, not all spectrophotometers are suited for every material or application. The geometry of the spectrophotometer plays a critical role in determining the effectiveness of color measurement. For instance, spectrophotometers with the 45°/0° geometry simulate how the human eye perceives color by illuminating the sample at a 45-degree angle and capturing reflected light at 0 degrees. This configuration is suitable for assessing the appearance of materials with uniform surfaces, such as painted plastics or smooth leather, and is often utilized for final visual quality inspections.

Another type of geometry is the d/8° geometry. Spectrophotometers using d/8° geometry provide diffuse illumination and capture reflected light at an 8-degree angle. This setup minimizes the influence of surface gloss or texture, focusing instead on the material’s intrinsic color. The d/8° spectrophotometer is ideal for measuring textured or glossy surfaces, such as grained plastics, fabrics, or naturally finished leather, where surface characteristics could otherwise affect the color measurement.

One of the advantages of d/8° spectrophotometers is their ability to measure in Specular Component Included (SCI) and Specular Component Excluded (SCE) modes. These modes are critical for obtaining comprehensive color data. For example, the SCI mode includes all reflections, including specular and diffuse reflections, capturing the “true” color of the material without considering the influence of gloss or surface texture. Conversely, the SCE mode excludes specular reflections, providing a measurement that aligns with how the material’s color appears when surface gloss and texture are factored in. This mode is particularly valuable for evaluating the perceived color of a material as it will appear to the human eyes. By alternating between SCI and SCE measurements, manufacturers can effectively assess the intrinsic color accuracy and the visual appearance of automotive interior components.

Effective Color Management of Automotive Interior

Color management in the automotive industry goes far beyond the use of spectrophotometers. It requires a holistic approach to maintain consistent color across all interior components. Achieving this consistency demands precise measurement, collaboration between stakeholders, and continuous monitoring throughout the production process.

A cornerstone of effective color management is the establishment of strict color standards and tolerances. These standards act as a reference point, ensuring every interior component aligns with the intended design and brand identity. Tolerances, defined by parameters like L*a* b* values or ΔE*ab values, outline the acceptable range of variation from the target color. Establishing tight color tolerances allows manufacturers to uphold high-quality standards while facilitating smooth collaboration with suppliers. It also helps reduce production errors, minimize waste, and enhance the efficiency of global supply chains, ensuring efficient operations and a consistent final product.

Konica Minolta Color Measurement Solutions for Automotive Interior

Konica Minolta Sensing, a leader in advanced measurement solutions, provides a wide range of precise and reliable color measurement instruments designed for the detailed evaluation of automotive interior components. Among these is the Konica Minolta Spectrophotometer CM-17d, a d/8° spectrophotometer with a vertical alignment design. The CM-17d delivers exceptional performance with a high inter-instrument agreement (IIA) of ΔE*ab < 0.12 and repeatability of ΔE*ab < 0.02, ensuring consistent and accurate color measurement across global supply chains. Featuring various color tolerance equations configured within the instrument and an electronic viewfinder for real-time previews, the CM-17d simplifies sample positioning while ensuring precise measurement results. Other noteworthy instruments include the 45°/0° Spectrophotometer CM-25cG and the d/8° Spectrophotometer CM-26dG. These spectrophotometers feature a streamlined, ergonomic design that makes it easy to measure in hard-to-reach areas, such as the tight spaces on dashboards near the windshield. The CM-26dG and CM-25cG offer high IIA and repeatability, pre-configured color tolerance equations, and an integrated 60° gloss sensor for simultaneous color and gloss measurements.

Spectrophotometer CM-17d (left), Spectrophotometer CM-26dG (center), and Spectrophotometer CM-25cG (right).