High solids coatings: A visual breakdown
There’s a lot of talk about high solids coatings among industrial coatings professionals these days. But outside of the circle of experts (and sometimes even within it), the concept can be a little fuzzy. Here’s a visual breakdown that hopefully simplifies main principals at work when we refer to high, or even 100 percent, solids coatings.
HIGHER SOLIDS, EVEN HIGHER COVERAGE
What are you really buying with your industrial coatings? The truth is, with low solids coatings, much of what’s contained in that can of paint you buy is destined to evaporate. Low solids coatings are largely made up of solvents, which exist only to make the actual coating (or “binder”) easier to apply. Higher and 100 percent solids coatings, on the other hand, have been engineered to be applied without the help of a solvent.
More mils, fewer coats
Paint specifications usually designate a mil thickness that a coating should reach on the surface being painted. Since solvents evaporate once a coating has been applied (usually as a result of exposure to oxygen), more of a coating must be applied once a solvent has completely evaporated. This is the difference between the wet lm thickness (WFT) and the dry lm thickness (DFT) of a coating. A specification aiming for a 20 mil DFT out of a 50 percent solid coating, for instance, would require two coats at 20 mils, whereas a 100 percent solid would require only one coat.
Why limit VOCs?
The Environmental Protection Agency regulates the emission of VOCs through what is known as the Architectural Rule for Volatile Organic Compounds. This rule limits the amount of VOCs manufacturers are able to emit during operation and can result in fees for exceeding the limits.
Infographic provided by US Coatings, a supplier and manufacturer of industrial coatings.