GMW GMW16146 PDF

The specification covers the durability and performance requirements for evaluation of new accent colors or pigmentation changes in approved accent color, basecoat or clearcoat technologies for exterior trim. This specification does not apply for topcoat colors which will be supplied to GM assembly plants or colors developed for exterior part sources that match topcoat colors for vehicle body.

Material Description. Materials qualified to this standard must meet the performance requirements as shown in Appendix A, Table A1, Table A2, and Table A3 and documents as shown in the examples in Appendix B, Figure B1, Table B1, Figure B2, and Figure B3. Additional testing may be requested in writing, by the responsible engineer.

Material Identification. Color description is to include:

Color name; GM-XXXX.

Color coding; WA-XXXX finish code.

Supplier code and batch number used for testing.

Applicable basecoat and clearcoat technologies, e.g., 998XXXX, L number or other regional or global specifications.

Note: XXXX is used as a placeholder for the color code number entered into the appearance database.

Qualified to this Material Specification. Testing per this specification is required by a change in pigment type or a combination of pigments not previously used together. In addition, a change in the level of a pigment or a change in Pigment to Binder (PB) ratio may also require this specification to be completed. The GM paint engineer will make the final decision whether or not to test such changes to the PB ratio.

Symbols. Not applicable. 

Applicability. The intent of the testing is to ensure that all future GM colors, in approved topcoat technologies, will meet performance criteria as affected by pigmentation. This testing generally includes evaluation of colorfastness, chip resistance, flexibility, and resistance to Ultraviolet (UV) transmission.

Performance criteria are dictated by the substrate/paint combination. Generally, all paints which apply to this standard must meet the requirements of GMW3005, Generic Topcoat Qualification.

All new accent colors are to complete two (2) years of outdoor exposure. If the new accent color uses pigments that have previously been evaluated, one (1) year is acceptable, provided that the color passes all other short term tests, including Xenon (4500 kJ/m²). Pigments do not include metal flakes.

For tint clearcoat colors, a minimum of two (2) years of outside exposure prior to production is required for all clearcoat technologies proposed, provided that all other short term tests including Xenon (4500 kJ/m²) have passed.

Annual Color Durability Review. Formal reviews of all exposure panels must be held and reports generated. Refer to all figures and tables in Appendix A and Appendix B. All panels shall be retained by the supplier.

Additional reviews will be held for individual pigment performance on proposal of use by a topcoat supplier.