Paint - Mica Refinish Information
REFERENCE BODYNUMBER 023
DATE 05-16-86
MODEL 1986 1/2 SUPRA
This bulletin explains the make up of a paint system known in the industry as mica or pearl, which is being used for the first time by Toyota on the new 1986-1/2 Supra. We will also describe some cautions when refinishing this type of paint system.
REFLECTIVE LIGHT:
1. MICA PAINT
Finely ground aluminum flakes are ordinarily used on metallic paints to reflect a small amount of light back to the observer, giving the paint a reflective brilliance that cannot be obtained from ordinary non-metallic paints. Since the aluminum flake used in metallic finishes has a silver tint and is not transparent, it is impossible to create a color with high metallic content that has bright colors. In the past, colors with high metallic content often became very muddy and washed out.
More recently, automobile manufacturers such as Toyota, have begun using colored mica flakes, which are semi-transparent and have optical characteristics which reflect a portion of the light striking the surface and at the same time, allowing the remainder of the light to pass through the flake until it strikes another flake particle. This optical characteristic provides a metallic paint that has very clear semi-transparent pearlescent metallic tones with deep, rich colors.
PAINT FILM CONSTRUCTION:
Superior Points
^ Very bright colors with excellent transparent depth.
^ High metallic pearlescent tones when viewed under direct light, especially direct sunlight.
^ Under weak light, the paint appears to be a solid non-metallic color.
II. Refinishing Information
Generally, the refinishing procedures used with this type of paint are the same as ordinary metallic paints; however, the following points should be observed.
^ Surface preparation is the same as the current metallic systems.
^ Depending on the type of refinish system being used and the manufacturer of the refinish products, the base coat or color coat is available in lacquer or enamel.
^ The top coat (clear coat) from the aftermarket paint suppliers is available in either acrylic lacquer, acrylic or urethane enamel. However, urethane enamel is more durable and is recommended for use as the clear coat over the base coat or color coat.
^ The brightness or pearlescent effect and the tint of the paint is greatly influenced by the amount of colored mica flakes mixed into the toners. The amount of colored mica flakes added to the toners should be precisely measured on a scale.
Note: Some paint manufacturers prepare ready mixed paint (factory packed) to prevent this mixing difficulty.
^ Since mica flakes are quite heavy, they have a tendency to sink to the bottom of a container, especially after mixing with a thinner or reducer. Therefore, mica type paints should be agitated constantly while mixing or spraying.
^ Repairs may require blending into adjacent panels because panel to panel refinishing is sometimes very difficult with pearlescent colors.
^ The red mica paint (color code 3H1) is semi-transparent, and therefore has very little hiding when it is applied over a primer coat. The painter should spray several coats, letting each coat flash dry three to five minutes between coats. Proper hiding cannot be achieved by trying to spray one thick coat over the primer.
^ It is necessary to spray pearlescent type paints in a well lighted environment. The use of an ultraviolet light while painting is an effective method of determining if the proper pearlescent tone effect has been achieved.
Comparison of Color Matching:
^ The results of mixing, spraying and color matching should be evaluated under direct sunlight where the characteristics of colored, mica pigment can be clearly seen. The comparison of color matching should be viewed from two different directions (as shown in the illustration below)..
^ Color 3H1 is currently available from:
Name Stock Number
Dupont G 8730
Sherwin Williams 34-36340
Ditzler 72886
Rinshed Mason A16396R(L)M16396F(E)
Sikkens TOY 3H1