GMW GMW18634 PDF

This specification covers the performance and qualification requirements for exterior, one-component (1K) solventborne basecoat and two-component (2K) solventborne clearcoat topcoats that perform over bake latitude of (82 to 135) °C ((180 to 275) °F).

Note: Nothing in this standard supercedes applicable laws and regulations.

Note: In the event of conflict between the English and domestic language, the English language shall take precedence.

Purpose/Material Description.

Basecoat (BC) components of these systems are typically 1K (solvent) acrylic melamine. Clearcoat (CC) components of these systems are flexible, 2K (solvent) urethane or urethane blends. Each combination of specific basecoat and clearcoat shall be tested and approved as a basecoat/clearcoat (BC/CC) system. The individual components are not interchangeable and are approved for use only with combinations of basecoat/clearcoat of the total paint system that were used in qualification testing.

Qualified to this Material Specification.

Each combination of specific BC and CC shall be tested and approved as a BC/CC topcoat system. The individual components are not interchangeable. This specification shall be used in conjunction with the GMW14797: Approved Paint on Plastic System (APOPS), a section of the GM Materials Approval Source List (GMMASL), which lists the approved substrate, cleaning, priming, and topcoat combinations. In addition, the topcoat system is part of the total coating system and shall meet qualifications set forth in this specification and those shown on engineering drawings for appearance and durability.

Symbols.

Not applicable.

Applicability.

These topcoats are typically designed to be applied over an adhesion promoter or a bake primer.

Note: All Thermoplastic Polyolefin (TPO) substrates using GMW18634 shall be primed with a GMW18417, GMW18418 adhesion promoter or flame treatment per GMW16133.

Remarks.

None.