DIN 53236 Determination of Color Differences for Paint Coatings, Similar Coatings and Plastics

The standard “DIN 53236 Coloring materials - Measurement and evaluation conditions for determining color differences for paint coatings, similar coatings and plastics”, published by the German Institute for Standardization (DIN), describes standardized conditions for measuring and evaluating color differences in paint materials. This standard is particularly applicable to paint coatings, similar coatings (e.g., varnishes) and plastics. It provides repeatable and comparable results when evaluating how much two colored surfaces differ in color appearance.

The DIN 53236 standard specifies precise instrumental measurement conditions and evaluation methods for measuring color differences between a reference sample and a test sample. This standard is widely used in the following areas:

Quality control in the paint and coatings industry.
Plastic production and coloring
Supplier-customer agreements regarding color tolerances.
Product specifications for films, granules, flakes, molded parts and decorative surfaces.

This standard focuses on objective, reproducible instrumental colorimetry rather than purely visual assessment (although visual controls often supplement this).

This standard covers:

Measurement geometry: We generally recommend common setups such as d/8 degrees (8 degrees of field of view with or without diffuse illumination and specular component) or similar configurations compatible with spectrophotometers.
Illuminator and observer: Typically a D65 daylight illuminator and a 10-degree standard observer (standard practice in modern colorimetry).
Color space and difference formula: The evaluation is based on the CIELAB (Lab*) color space. The color difference is calculated using the following components, together with CIE formulas:
L = Difference in span
a = Red-green difference
b = Difference between yellow and blue
Sample preparation and presentation conditions (e.g., opaque, non-fluorescent, flat surfaces).
Interpretation of tolerances and pass/fail criteria (usually agreed upon between the parties, e.g., stricter tolerances such as a maximum color difference of 0,6 or a maximum color difference of 0,3 in applications requiring high demand)

This standard primarily describes the following procedures:

Procedure A refers to instrumental color difference measurement under defined standard conditions without specific visual assessment corrections. It is the basic and most commonly applied assessment procedure. This procedure is used for:
To determine color differences between the test sample and the reference sample.
To evaluate color changes after stress exposure (e.g., weather exposure, heat, chemicals).
To provide objective, instrument-based evaluation.
To provide repeatable laboratory comparisons.

This procedure is primarily applied in quality control and product conformity testing for coatings and plastics.

Procedure B is an alternative to Procedure A, combining instrumental measurement with visual evaluation under controlled conditions. It is typically used when human eye color perception is important in addition to numerical color difference values. This procedure is designed for the following purposes:
Evaluating color differences by taking human visual perception into account.
Taking metamerism into account (two samples appearing the same under one light but different under another light)
Completing instrument measurements for quality control in coatings and plastics.
Supporting final product approval, especially in situations where end-user perception is important.

The DIN 53236 standard is closely aligned with international standards such as “ISO 7724 Paints and varnishes – Colour measurement” and CIE recommendations, but provides specific guidance focused on German industry.

Many testing laboratories explicitly present color measurements according to DIN 53236 Part A/B. These are frequently used as references in the following areas:

Automotive paints
Architectural paints
Plastic films and decorative laminates
Product data sheets specifying color consistency (e.g., color difference not exceeding 0,6 according to DIN 53236 standard)

Some manufacturers specify different tolerances.

DIN 53236 remains an important reference in German-speaking countries and in sectors requiring precise, standardized color control for quality assurance of colored materials.

In short, the DIN 53236 standard is an important standard that defines how to measure and evaluate color variations in coatings and plastics, particularly paints, varnishes, similar surface coatings, and pigmented or dyed plastic materials. This standard specifies standardized measurement and evaluation conditions used in quality control, testing, and the assessment of color consistency and variations under various influences.

This standard specifies procedures for measuring and evaluating how the color of coatings and plastics differs from reference values or changes due to stress.

This standard applies to pigmented and non-pigmented materials, as well as materials containing soluble colorants. It is particularly important in situations where physical or chemical stress (e.g., environmental exposure, aging, process conditions) may cause color change.

It provides a uniform basis for color difference assessment and ensures that results from different laboratories or companies are comparable. This is a crucial aspect of quality control, production consistency, and specification compliance in the coatings and plastics industries.

This standard generally defines the following:

Measurement conditions include light source types (e.g., standard illuminators like the D65), imaging geometry, and instrument setup.
Evaluation criteria for quantifying color differences (typically based on standardized color spaces such as CIELAB color values).
Procedures for comparing test samples to references to identify color shifts.

The main reasons why this standard is important for coatings and plastics are as follows:

Instead of relying on subjective visual comparison, it provides repeatable and objective color measurement.
It supports product quality assurance (e.g., consistency from batch to batch).
It helps in assessing the effects of aging and stress, such as fading, yellowing, or discoloration after environmental exposure.
It is often used in conjunction with other standards (e.g., ISO/EN color measurement standards).

In conclusion, the DIN 53236 standard is a fundamental normative reference for anyone involved in color measurement in the paint, coatings, and plastics industries, offering standardized conditions and methods for objectively and consistently assessing color differences.

For many years, our organization, with its competent and experienced staff, has been understanding the needs of its clients, providing the advanced testing services they require, and assisting them in the establishment, implementation, and improvement of management systems. Within this framework, we also provide testing services in accordance with the DIN 53236 standard.