ABS Trouble Shooting - Painting Defects

As the easiest plastic to paint, ABS is widely used for painted components. Nevertheless, painting defects can occur as a result of factors such as grade selection, molding conditions, paint and thinner characteristics, and painting method. The following photographs are provided in order to allow painting defects to be better understood, thus contributing to their resolution.

Main painting defects
(Click the links on the left of the photographs below for more information on causes and countermeasures) We recommend our special painting grades for use in painted products.

Pinholes

Often seen in urethane painting, this phenomenon is characterized by the appearance of small holes on the painted surface, and it is also known as "cratering."

Cracks

As with pinholes, these fine cracks on the painted surface are caused by solvent attack, and this phenomenon is often seen in acrylic painting. These cracks generally occur near gates and at edges in particular.

Sinking Solvent

From the paint penetrates the component near the gates, at areas of varying thickness, or near welds; consequently, luster becomes uneven and fine cracks develop.
(Photograph shows metallic paint.)

Cissing

With indentations of 1 mm or more in diameter occurring on the painted surface, this phenomenon results in the substrate becoming visible.

Poor adhesion

One of a number of phenomena where paint peels from the surface of the component, poor adhesion is generally identified during adheasion testing.

Others
Lifting	Wrinkling occurs when multiple layers of paint are applied (i.e., repainting).
Orange peel	Rather than being flat and smooth, the surface takes on the appearance of orange peel, with numerous small bumps and indentations.
Whitening	The surface of the painted component becomes cloudy and white. (Often occurs with acrylic lacquers.)
Welds	Welds on the surface of molded components become more obvious after painting.