Exterior Paint Topcoat Color Qualification
|Publication Date:||1 September 2015|
1.1 Material Description. This specification covers the durability and performance requirements for evaluation of pigment combinations or pigmentation changes in all GM Colors in approved basecoat or clearcoat technologies. These materials are identified by color name, color description, e.g., solid, metallic, tricoat, tinted clearcoat, etc., WA-XXXX finish code, supplier code, batch number used for testing, basecoat and clearcoat system number 998XXXX (where applicable), L-number or other regional number, Target Bake Temperatures (T) and target time at substrate temperature.
Symbols. Not applicable.
Applicability. This specification covers all rigid and flexible topcoat colors which will be supplied to GM assembly plants or outside part sources. Performance criteria is dictated by the substrate/paint combination (Type and Class of the topcoat). This standard applies to Topcoat Classes 1 and 2 only. See GMW3005. Testing per this specification is required for 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 ratio may also require this specification to be completed.
Note: Colors are to be released for production after a minimum of 2 years Florida exposure (must include 2 full summers) with the primary color development supplier and a minimum of 1 year Florida exposure with the secondary color development suppliers and parts paint suppliers. All colors are to complete 5 years of outdoor Florida exposure, up to a maximum of 10 years depending on color usage and performance.
Remarks. Materials qualified to this standard must meet the performance requirements as outlined in Appendices A and B. Additional testing may be requested in writing, by the responsible GM engineer. The intent of the testing is to ensure that all GM colors, in approved topcoat technologies, will meet specified performance criteria as affected by pigmentation. This testing generally includes evaluation of colorfastness, chip resistance, flexibility and resistance to Ultraviolet (UV) transmission. Exposure testing is required for colors in all basecoat technologies being supplied.
Exposure under all clearcoat technologies is not required for conventional colors, however, tinted clearcoat colors must be exposed in all clearcoat technologies supplied.
Formal reviews of all exposure panels must be held annually and reports generated per Appendices A and B. All panels shall be retained by the supplier and provided for these reviews until completion of 5 years exposure testing up to a maximum of 10 years.
Colors in all basecoat technologies used for fascias must be evaluated on flexible substrates, even though an identical basecoat color is used for body paint technology.