Translucent Color, Spectral Grays

Visual representation of the spectral gray, translucent basecoat, and clearcoat layers.As automakers look to differentiate their vehicles from the competition, offering eye-catching exterior colors is one proven way to attract the new car buyer. That's clearly evident when you look at today's OE color palette, which is significantly more exotic and vibrant than it was even five years ago. Many of the newest selections are highly chromatic, with translucent colors that sparkle with an exceptional level of depth, brilliance, and clarity.

In order for collision repair centers to accurately match these increasingly popular, vibrant colors, it's helpful to better understand the factory application process, as well as the progressive pigment technologies involved in creating these more exotic OE finishes. For example, an OE color like Toyota's 3R1 Matador Red is a "tri-coat" finish with an abundance of sparkle and depth of hue. Its sister color, 3R3 Barcelona Red, has an even brighter, rich red appearance, but its brilliance is achieved using a combination of translucent pigments and red pearls in a basecoat/clearcoat application.

Visual representation of the spectral gray shades.
The spectral gray system consists of 5 different shades.

These vibrant translucent colors can create challenges for the collision repair technician seeking to create successful repairs to these finishes. Not only must an accurate match be achieved—it should be invisible to the naked eye to be a sucess. For true accuracy, this requires a new approach to the color matching repair process—one PPG has taken the lead in developing.

Automotive OE manufacturers do not all use the same application process to get the same effect. Some use standard gray undercoats for all colors; others employ different shades of gray, while others apply colored ground coats. But the end result is effectively the same—the translucent nature of the intense color pigments combine with the undercoat color and clearcoat to create the dramatic final color.

Waterborne toners and the spectral gray undercoat system

PPG's innovative spectral gray process mimics the OEM approach by incorporating the latest vibrant waterborne toners and translucent pigments with a scientifically proven spectral gray (SG) undercoat system. As in the factory process, an SG undercoat contributes to the final basecoat color and is critical to matching the OE finish. PPG has formulated five shades of spectral grays—G 1, 3, 5, 6 and 7—giving collision repair technicians the complete range needed to match today's emerging translucent colors. All of PPG's waterborne color formulas specify the optimal SG shade of undercoat, which can be retrieved from any of PPG's color formula retrieval tools.

Visual representation of the G3, G5 and G6 spectral gray shades under a translucent red color.
G5 is the recommended PPG spectral gray for matching Toyota's Barcelona Red, code 3R3. Notice how each shade of gray influences the final color.

Apply to match vs. spray to full hiding

"Spray to full hiding" has long been the maxim for any paint technician applying color coats over primer to accurately match a vehicle color. This is no longer standard practice when repairing the newer translucent OE finishes using PPG's advanced waterborne color matching process. Once the recommended SG undercoat is applied, coats of the waterborne translucent color are sprayed to "perceived hiding," allowing the sealer to play its role in creating the final match. Typically, this "apply to match" technique requires two to four coats of color, plus a lower-pressure control coat to create a smooth metallic orientation.

Smoother, easier blending

Technicians accustomed to spraying opaque color to full hiding over a feather-edged surfacer will discover a significant advantage in blending when transitioning to PPG's waterborne system. Using the traditional "spray coverage to full hiding" with products formulated to be opaque, painters can find it difficult to achieve both a good color match and a satisfactory blend into adjacent panels on newer translucent colors. In comparison, PPG's waterborne toners, combined with blended SG undercoats, enable the painter to achieve a gradual blend that vanishes into the adjacent OE finish. This easy blending technique for spot repairs is often touted by collision centers as one of the major reasons why they converted to PPG's waterborne technology—and it's an essential part of the curriculum being taught by all PPG training centers.

Given PPG's never-ending quest to advance the art and science of color matching, you can have confidence that PPG Refinish will keep pace with OE color styling as it continues to evolve into the future. For additional information on the PPG spectral gray process and products, please contact PPG Refinish Product Support hotline by calling 800.647.6050, option 4.

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