Color and gloss control instruments

Color and gloss control makes it possible to objectively assess the appearance of surfaces, materials and coatings. In many production processes, visual observation alone is not sufficient: color, color differences, gloss, metamerism, whiteness and reflectance can affect perceived quality, consistency between batches and material conformity with the reference standard.

This category includes instruments for color measurement, color analysis, visual evaluation under controlled illuminants, gloss measurement, whiteness control and reflectance verification. Each instrument addresses a different requirement: it is therefore important to distinguish correctly between colorimeters, spectrophotometers, glossmeters, light booths, whiteness meters and reflectance meters.

Color control with colorimeters and spectrophotometers

Colorimeters are portable instruments suitable for rapid color checks and comparison between a sample and a standard. They make it possible to assess color differences through numerical values, such as Delta E, and are useful when the objective is to verify color consistency on plastics, paints, coatings, textiles, printed surfaces, industrial components and colored materials.

Multi-illuminant models allow inspections to be carried out under different lighting conditions, providing a more complete assessment when color must be verified under different light sources. This feature is useful in sectors where a sample may appear compliant under one lighting condition but different under another.

Spectrophotometers are more suitable when a more in-depth color analysis is required. Compared with a colorimeter, they make it possible to work with the spectral response of the sample, reflectance curves and metamerism evaluation. They are therefore suitable for more complete color control, quality management of colored materials and comparison between different production batches.

For metallic, pearlescent or special-effect coatings, a multi-angle spectrophotometer makes it possible to observe color variation across several measurement angles. This solution is particularly useful when color changes according to the viewing angle, as occurs in many automotive, decorative and industrial finishes.

Gloss measurement with glossmeters

Gloss is a parameter different from color. A surface may have the same color as a reference sample but appear glossier, more satin or more matt. For this reason, gloss measurement is carried out using glossmeters, instruments dedicated to assessing surface appearance.

Glossmeters can operate with different measurement geometries. The 60° angle is used as the general reference, while 20° is suitable for very glossy surfaces and 85° for satin or matt surfaces. Instruments with dedicated geometries for specific applications, such as ceramics and paper, are also available.

For surfaces with very high gloss values, such as highly glossy finishes or mirror-polished surfaces, it is preferable to use a glossmeter with an extended measuring range. When the sample instead has small areas, small objects or curved surfaces compatible with correct instrument positioning, a glossmeter specifically designed for small surfaces is more suitable.

Glossmeters with memory and data output are useful when quality control requires recording, comparison and management of measurements. This makes it possible to collect values, reduce transcription errors and maintain more organised documentation of completed inspections.

Color matching cabinets for visual color evaluation

A color matching cabinet is used for visual color evaluation under controlled illuminants. It is not a numerical measuring instrument, but it allows the sample to be observed under repeatable lighting conditions, reducing the influence of the external environment.

It is particularly useful for verifying color matching between materials, samples, production batches or different supplies. The color matching cabinet also helps identify metamerism, namely situations in which two samples appear similar under one light source but different under another.

Color matching cabinets are used in sectors such as textiles, fashion, leather goods, packaging, printing, plastics, paints, furniture, industrial components and material quality control. They are often used alongside colorimeters and spectrophotometers: the instruments provide the numerical data, while the cabinet allows visual assessment under controlled conditions.

Whiteness, reflectance and hiding power

A whiteness meter is used to determine the whiteness value of light-colored materials, surfaces, powders or samples compatible with the measuring method. It is suitable when the objective is not to analyse the full color, but to control the degree of whiteness of the material specifically.

A reflectance meter is instead used to assess surface reflectance and the hiding power of paints, coatings, films, inks, pigments and plastic materials. It is useful for comparing samples applied over black and white backgrounds, verifying how effectively the material covers the underlying substrate.

These instruments should not be confused with glossmeters, which measure gloss, or with colorimeters and spectrophotometers, which are dedicated to color measurement and analysis. Each parameter describes a different aspect of the surface and must be controlled with the most suitable instrument.

How to choose the correct instrument

Instrument selection depends on the parameter to be checked. Colorimeters or spectrophotometers are used to measure color differences and color values. To assess metamerism or obtain a more complete color analysis, a spectrophotometer is the most suitable solution. A color matching cabinet is used to assess samples visually under different light sources.

When the parameter to be verified is gloss, the choice is a glossmeter, selected according to the measurement geometry, gloss range, sample shape and the need to manage data. A whiteness meter is used to control whiteness, while a reflectance meter is used for reflectance and hiding power.

A complete assessment of surface appearance may require several complementary instruments. Color, gloss, whiteness and reflectance do not describe the same characteristic, but together they allow a more complete evaluation of the aesthetic and functional quality of the material.