MBN 10494-7 Paint Test Methods - Part 7: Resistance to Chemicals, Test Mixtures, and Test Concentrates

The standard “MBN 10494-7 Paint test methods - Part 7: Resistance to chemicals, test mixtures and test concentrates” developed by the Mercedes Benz Group describes test methods for examining the quality and properties of paints, varnishes and coatings in the following cases:

• At the time of delivery for further processing at Mercedes Benz Group facilities
• In the body and main component area, plastic and other functional parts are coated

The relevant requirements are contained in material-specific standards.

Dye testing methods are used to:

• Laboratory tests, e.g. basic examinations, initial tests, retests, tests in case of operational complaints
• Process control of coating in Mercedes Benz Group facilities

The general requirements in this standard are described as follows:

• Current legal requirements and laws regarding safety, homologation (especially exhaust emissions), and quality must be complied with. The relevant requirements of the Mercedes-Benz Group also apply.
• All materials, procedures, processes, components, and systems must comply with current legal requirements regarding regulated substances and recyclability. Standards DBL 8585 and DBL 6714 apply for information on prohibited and declarable substances.
• In the case of all coating materials, care must be taken to ensure the lowest possible odor and the lowest possible volatile substance content (e.g. solvents, plasticizers).
• Preparations/coating materials must be labeled in accordance with legal regulations and must be provided with the necessary information for transport and use. If used abroad, the regulations and rules applicable to those countries must also be adhered to.

When determining resistance to chemicals, test mixtures, and test concentrates, the DBL 7384 standard applies to testing the chemical resistance of coated plastic parts in vehicle interiors. These tests can be performed on test panels in accordance with the "Sampling, test panels" section of the MBN 10494-1 standard. The paint texture of the samples must be compatible with the paint texture of the relevant application area. It must be determined whether visible surface changes have occurred (such as gloss change, color change, cracking, blistering, swelling, shrinkage).

Tests for resistance to chemicals, test mixtures and test concentrates include:

• Chemical resistance - Temperature gradient oven test method: Chemical resistance testing is used to determine the resistance of automotive paints to tree resin, bee and bird droppings, rainwater and similar external environmental influences.
• Resistance to chemicals - At room temperature / elevated temperature: Exposure time and temperature are specified in the material-specific standard.
• Resistance to test fuels: Exposure time and temperature are specified in the material-specific standard.
• Resistance to process materials and service products: Exposure time and temperature are specified in the material-specific standard.

Like many proprietary standards published by automotive original equipment manufacturers, the MBN 10494-7 standard plays an important role in ensuring the quality, consistency and performance of components and materials used in vehicle production.

The MBN 10494 series of standards consists of several sections, each outlining specific test procedures, acceptance criteria, and material requirements. These are typically applied to plastic components, elastomers, and coatings that must meet stringent standards to ensure long-term performance in automotive environments. Each section of the series covers a different test method or material property. The MBN 10494-7 standard focuses on a specific set of tests or material criteria. This standard covers test procedures for weatherability, aging behavior, or material compatibility. These primarily concern:

• thermal aging
• UV resistance
• Chemical exposure
• Stress crack or mechanical failure

Compliance with the MBN 10494-7 standard is generally mandatory for Mercedes-Benz suppliers. These standards help ensure:

• The parts maintain their integrity throughout the expected life of the vehicle.
• The materials do not deteriorate under extreme environmental conditions.
• The components meet the Mercedes-Benz Group's brand reputation for durability and safety.

This standard plays a role in supplier qualification, material approval, and product verification. This standard references or may incorporate international test methods such as ISO 4892 (artificial weathering) or ISO 527 (tensile properties of plastics), but modifies them to reflect the specific in-service conditions found in Mercedes-Benz vehicles.

Access to the MBN 10494-7 standard is generally limited to certified suppliers, R&D partners and contract laboratories.

This standard is important because it plays a critical role in ensuring the performance, durability, and safety of the materials and components used in Mercedes-Benz vehicles. The key reasons for this standard's importance are:

• Ensures the use of high-quality materials: This standard specifies specific requirements for material testing and performance (related to aging, weather resistance, or chemical resistance). This ensures that all parts (especially plastics or polymers) meet Mercedes-Benz's high standards. Poor-quality materials can degrade under sunlight, heat, or chemicals. This standard ensures that components remain functionally and visually acceptable throughout the vehicle's lifespan.
• Protects vehicle reliability and brand reputation: Mercedes-Benz is known for its engineering excellence. If suppliers use substandard materials, parts can crack, fade, or fail, leading to warranty claims, safety issues, and loss of consumer confidence. This standard provides a safeguard against this, helping Mercedes-Benz maintain its reputation for superior quality.
• Standardizes testing across the supply chain: This standard provides a common reference for all suppliers and laboratories at Mercedes-Benz. This ensures consistent testing methods, reliable and comparable results, and fewer errors and misunderstandings. This is essential in a global supply chain involving hundreds of suppliers.
• Supplier approval requirement: For a supplier wishing to work with Mercedes-Benz, compliance with MBN 10494-7 is generally non-negotiable. Non-compliance can disqualify a product or material from use.
• Encourages innovation and material improvement: Because this standard is stringent, it forces suppliers to:
  • Using better formulations
  • Investing in advanced material technologies
  • Innovating for longer-lasting, more sustainable products

This standard raises the technical bar for the entire automotive materials industry.

Consequently, the MBN 10494-7 standard is one of many technical standards used by Mercedes-Benz to ensure the reliability and performance of the materials used in its vehicles. Its importance in the automotive supply chain cannot be overstated. Suppliers aiming to work with Mercedes-Benz should be familiar with these standards and conduct in-house testing or partner with certified laboratories to demonstrate compliance.

Our organization, which has been serving for many years and meticulously following global developments in science and technology, employs a skilled team and extensive infrastructure to conduct testing, measurement, and analysis in a wide range of areas for businesses across all sectors. In this context, we also provide testing services in accordance with the standard "MBN 10494-7 Paint test methods - Part 7: Resistance to chemicals, test mixtures, and test concentrates."