Paint Degradation in Paint Circulation Systems

Paint degradation affects manufacturers – most notably automotive factory paint shops – who use metallic particle paints to produce high quality surface finishes. As metallic flakes move through a paint circulation system, they may get bent or broken. This can damage quality and color match so much that the paint must be discarded.

What is Paint Degradation?

Paint degradation (sometimes called “paint shear”) is the change in light reflection of a finished surface due to changes in the coating’s ability to reflect light.

Diagram of the desired effect of light on "effect" pigments show light going from an incident light source. The light bounces off the metal pigments to reflect differently at different angles.

To achieve the desired appearance of a coated surface, pigments and particles are added to the paint chemistry. These usually include metallic particles or metal flakes that reflect light off a normal flat surface.

Diagram of the reduced effect of light on "effect" pigments show light going from an incident light source. The light bounces off the damaged metal pigments to become diffused, making the surface dull..

When paint particles are deformed through the circulation process, light reflection changes because changes in pigment or flake shape cause a diffused reflection of light.

How Does Paint Degradation or Paint Shear Occur?

Paint degradation or paint shear occurs when metallic particles, meant to reflect light for a desired effect, deform. When the particles bend or break, the light reflected off of the finished surfaced changes, reducing the quality of finish appearance.

As metallic particles pass through a circulation system, they are deformed in particular components (usually a back pressure regulator or pump). The longer the paint circulates, the more deformation or damage occurs.

How to Avoid Paint Waste

There always will be some degree of degradation or shear of paint as it circulates through a system. Lessening the effects of paint degradation involves proper system design and active management techniques. Such steps not only extend the life of the material in circulation, they also help you avoid the high disposal costs of paint that no longer produces the appearance desired.

 

Colorful line precedes form to download white paper about paint degradation, also known as paint shear.

 

 

Download White Paper

Our free white paper, Paint Degradation in Paint Circulation Systems, further explains what paint degradation is, how to detect it with color space and measurement, what causes paint degradation, and how to mitigate its effects.

Simply fill out this form to immediately receive the free, five-page guide.

 

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