Material Description. This specification covers the requirements for a stand-alone, conductive, sealing primer for Sheet Molded Compound (SMC) substrates including those with in-mold coatings.

• Type 1 primers have a target bake < 121 °C (250 °F).

• Type 2 primers have a target bake ≥ 121 °C (250 °F).

• Gloss values ≤ 60 units on a 60 degree meter are permissible

This primer is part of the total painted product system and must provide a smooth, adhesion-promoting coating direct to substrate or in-mold coating and to subsequent coatings. The primer must be sandable and act as a barrier to prevent popping of topcoats during subsequent bakes.

Specifications Qualified to this Material Specification. This primer is part of the total painted product system and must meet requirements set forth in specifications for other materials with which it is used. This specification shall be used in conjunction with the Approved Paint on Plastics System (APOPS), a section of the GM Materials Approved Source List which lists approved substrate, cleaning, priming, and topcoat combinations. APOPS test requirements are defined in GMW14797.

Symbols. Not applicable.

Applicability. Primers covered under this specification are typically applied to SMC plastic exterior body panels. Primers are used under an approved body topcoat system.

Remarks. None.