GMW GMW15202 PDF

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.

This specification covers base paint film material technology (or construction) approval requirements and the performance requirements of exterior plastic parts decorated with paint film. Examples are emblems, illuminated trim, rocker moldings, air dams, body-side moldings, body claddings, mirror housings, appliques, inserts, lamp housings, grilles, and fasciae.

Symbols.

Not applicable.

Applicability.

Type I constructions are used for exterior parts such as rockers, appliqués, fasciae, etc. on first surface applications. This construction uses a thermoplastic polyolefin (TPO or PP+EPDM) substrate with an acrylic color coat and clear coat. This type is intended for matching body color paint.

Type II constructions are for bright film on first surface applications. These films are used to achieve chrome-like or tinted chrome-like appearance for illuminated or non-illuminated applications. For tinted applications, the clear coat may be tinted, or an optional tinted color coat may be added between the metallized layer and the clear coat. Each optional construction requires separate base material approval.

Type IIA uses an acrylic, or poly(methyl methacrylate) (PMMA), substrate layer with acrylic color coat and clear coat.

Type IIB uses an acrylonitrile butadiene styrene (ABS) substrate with acrylic color coat and clear coat. If there is no substrate suffix on a callout (legacy), assume Type IIB.

Type IIC uses a polycarbonate (PC) substrate with acrylic color coat and clear coat.

Type III constructions are used for emblems for first surface applications (e.g., Chevrolet bowties, GMC letters). This construction uses an acrylonitrile butadiene styrene (ABS) substrate with an acrylic color coat and clear coat.

Type IV constructions are used for second-surface molded behind poly(methyl methacrylate) PMMA applications. These may or may not have a metallized layer, denoted with a lowercase “m” in the callout.

Types IVA and IVAm use an acrylic, or poly(methyl methacrylate) (PMMA), substrate layer with acrylic color coat and clear coat.

Types IVB and IVBm use an acrylonitrile butadiene styrene (ABS) substrate with acrylic color coat and clear coat.

Types IVC and IVCm use a polycarbonate (PC) substrate with acrylic color coat and clear coat.

Type V constructions are used for second-surface, molded behind polycarbonate (PC) applications. These may or may not have a metallized layer denoted with a lowercase “m” in the callout.

Types VA and VAm use an acrylic, or poly(methyl methacrylate) (PMMA), substrate layer with color coat and clear coat.

Types VB and VBm use an acrylonitrile butadiene styrene (ABS) substrate with color coat and clear coat.

Types VC and VCm use a polycarbonate (PC) substrate with color coat and clear coat.

Illumination Suffix.

Types II through V may have the optional suffix ‘-L’, which denotes an illuminable film. This generally means that the substrate material is transparent or translucent. The nominal light transmissivity may vary from 5% to 20% and shall be determined by cooperation between Appearance Engineering and the PDT. Each required light transmissivity level shall be approved as a separate color approval. The transmissivity level will be documented in the Trim Transmittal notes.

Decoration (Deco.) Suffixes. Each type described in 1.3.1 through 1.3.5 may have any of the optional suffixes that follow. For approval to these suffixes, the undecorated film material shall be approved as a Base Material. The decoration materials shall be approved under a trim transmittal.

Suffix “-DEC-A” denotes decoration on the “A-side” of the film (the acrylic/clear coat side).

Suffix “-DEC-B” denotes decoration on the “B-side” of the film (the plastic substrate side).

For some finishes for types II through V, the color coat and clear coat layers may be combined into a single tinted layer if the performance requirements are met. This construction method requires separate base material approval under the applicable callout.

Remarks.

Finished parts are made from thermoformed sheet stock for Type I thick-film TPO applications. For all other types and for Type I thin-film applications, the film shall be thermoformed into a preform and placed into an injection mold where plastic is injected onto the preform to make a finished part.

For all types, the co-molded injection-molded material use on parts and test samples shall be listed as approved on the GM Materials Approved Source List (GMMASL) and agreed-to by the GM Material Engineer. In addition to the co-molded injection-molded materials listed in 1.4.1.1 through 1.4.1.4, sustainable alternatives should be use where available, at the discretion of the GM Material Engineer.

For Type I, injection molded materials shall meet the requirements of a GM Worldwide material callout for TPO, such as GMW16826P-PP+EPDM-M12-T1, per the Preferred Material Catalog (PMC); see GM materials engineer.

For Type IIA and IV, injection molded materials shall meet the requirements of GMW16335P-PMMA-T4 or as directed by the GM materials engineer. Note: Utilize a 4 mm-thick plaque (overall target (4 × 6) in) over molded onto the film for Base Material approval testing.

For Types IIB, and III injection molded Acrylonitrile Butadiene Styrene (ABS) materials shall meet the requirements GMW15572P-ABS-T2 or GMW15572P-ABS-T5, as applicable, or as directed by the GM materials engineer.

For Types IIC and V, injection molded materials shall meet the requirements GMW16729 (optical PC), as applicable to the part drawing. In some cases, other approved PC materials be substituted with the agreement of the GM Material Engineer.

Typical (but not exhaustive) paint film constructions are shown in Appendix B. The use of a masking film is optional and shall be incorporated into testing for Validation Testing Complete (VTC) approval.