TPJLR.52.551 Discoloration of Organic or Decorative Coatings and Flooring Materials Due to Dry Heat

Jaguar Land Rover Limited (JLR) standard "TPJLR.52.551 Discoloration of organic or decorative coatings and trim materials by dry heat" describes a test procedure applicable to all organic or decorative coatings and trim materials fitted to all Jaguar and Land Rover products. This test procedure describes a recommended procedure for determining the dry heat discoloration of organic or decorative coatings and trim materials when in contact with natural or synthetic rubber, felt, or other materials that may cause staining. This procedure is intended to simulate the risk of discoloration when products such as weather seals are in constant contact with decorative surfaces.

A valid risk assessment must be carried out before this test is performed.

This standard must be reviewed and reapproved for continued use at least every three years from the date of last approval.

All equipment used in testing must be up-to-date and certified for calibration. Key equipment includes:

• Laboratory oven capable of maintaining specified temperature.
• Glass or metal plate (minimum size 80 mm x 80 mm plus/minus 2 mm)
• 5,0 kg weight.
• A suitable indoor shampoo or outdoor pure shampoo depending on the application of the part.
• Sponge or cotton.

Tests use a 70 mm x 70 mm plus/minus 2 mm specimen cut from the component under test or a representative test plate. If the component is smaller than this, multiple sections can be combined to achieve the required size.

The test panel should be of a size and shape that will cover the test sample when in contact with it and extend at least 30 mm in one direction to facilitate the assessment of any migration stains. The panel should have the following characteristics:

• Painted: In accordance with normal manufacturing procedure and ambient aged materials shall be as follows:
  • Baked surfaces: 1 day
  • Air-dried and low-temperature oven-baked surfaces: 7 days

Unless otherwise specified, color should be white for solid colors and silver for metallic finishes.

• Other coatings: Unless otherwise specified, light colours are used.

All test values ​​stated herein are based on material conditioned in a controlled atmosphere of 23 degrees plus/minus 2 degrees and 50 percent plus/minus 5 percent relative humidity for at least 24 hours prior to testing and tested under the same conditions, unless otherwise stated.

During the test, the test specimen is placed centrally in contact with the test panel (i.e., a painted panel or other suitable material). A glass/metal plate is placed on top of the test specimen, and a 5,0 kg load is applied to maintain the test specimen in contact with the test panel. The assembly is placed in a laboratory oven for 24 hours at a temperature of 70°C plus/minus 2°C, or an alternative temperature specified in the material standard. The oven must be free of other materials that could cause staining. After the heat exposure is complete, the assembly is removed from the oven, allowed to cool to room temperature, and the weight, plate, and test specimen are removed from the test panel. If necessary, the surface of the test panel is cleaned using a suitable indoor or outdoor shampoo and a sponge/cotton swab. The test panel is inspected for any stains and visually inspected using the grayscale specified in ISO 05-A02 and equipment specified in "TPJLR.52.206 Northern sky daylight only - 6500°K." The test panel is placed in an accelerated weathering (UV) chamber and subjected to an exposure cycle. The test panel is then visually inspected using the grayscale specified in ISO 05-A02 and the equipment specified in TPJLR.52.206.

The test panel is examined after a heating cycle and again after a UV exposure cycle. If the tested sample does not meet the standard for the material being evaluated in either cycle, it is considered unsatisfactory.

Land Rover (JLR) is renowned for its commitment to producing luxury vehicles that combine aesthetic excellence with durability. A number of engineering standards, including TPJLR.52.551, are used to ensure that vehicle components maintain their quality under real-world conditions. This standard specifies test methods for evaluating the resistance of materials to cleaning agents and ensuring that surfaces can withstand exposure to chemicals commonly used in vehicle maintenance. The cleaning agents exposed include detergents, solvents, and other chemicals used in vehicle interior and exterior cleaning. This standard ensures that materials maintain their appearance, structural integrity, and functionality, even after repeated exposure to such agents. This standard aligns with STJLR.51.5226, which governs the properties of materials throughout JLR's supply chain, and is part of a broader suite of engineering standards.

The TPJLR.52.551 standard applies to a variety of components, including:

• Interior surfaces: Upholstery, dashboard panels and leather or synthetic trim that can be cleaned with detergents or solvents.
• Exterior surfaces: Painted body panels, bumpers, and alloy wheels exposed to cleaning products such as rim cleaners or car wash solutions.
• Functional components: Seals, gaskets, and other parts that may come into contact with cleaning chemicals during maintenance.

This standard applies specifically to materials that must withstand frequent cleaning without showing signs of discoloration, cracking, or loss of adhesion, ensuring both aesthetic durability and customer satisfaction.

The TPJLR.52.551 standard is critical for the following reasons:

• Aesthetic durability: Cleaning agents can fade or damage surfaces, which can negatively impact the premium appearance of JLR vehicles. This standard ensures that materials remain visually appealing over time.
• Durability: By verifying resistance to chemical degradation, this standard helps extend the life of components and supports JLR's long-term warranties, which can exceed 10 years for certain parts.
• Customer experience: Vehicles that withstand regular cleaning without damage increase customer satisfaction, reinforcing JLR's reputation for quality.
• Real-world compatibility: This standard simulates common cleaning applications, ensuring materials perform reliably in the conditions encountered by vehicle owners.

Implementing the TPJLR.52.551 standard presents several challenges:

• Material compatibility: Manufacturers must select materials that balance cost, performance, and resistance to a wide range of cleaning chemicals.
• Test variability: Differences in cleaning agent formulations or test conditions may affect results and require strict adherence to JLR protocols.
• Evolving consumer practices: As new cleaning products come to market, the standard may need to be updated to reflect changing real-world conditions.

As a result, the TPJLR.52.551 standard is a vital component of Jaguar Land Rover's quality assurance strategy, ensuring that vehicle materials can withstand exposure to cleaning agents without compromising appearance or functionality. By implementing rigorous testing protocols, JLR fulfills its commitment to producing durable, high-quality luxury vehicles that meet customer expectations. Suppliers and manufacturers must comply with this standard to contribute to the longevity and aesthetic appeal of JLR vehicles.

Our organization, which has been operating for many years and meticulously follows 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 "TPJLR.52.551 Discoloration of organic or decorative coatings and flooring materials due to dry heat."