Do you have a favorite color—or a favorite set of colors? Most people do. Think of your favorite colors and where you like to see them. Nature, cosmetics, jewelry, clothing, artwork, furniture, appliances, (all consumer goods), cars, building interiors and exteriors—the list is practically infinite—everything we can see reflects some kind of color. Outside of those things that are colored by nature, the intentional coloring of things is serious business! And creating color is one of the things ICD High Performance Coatings does best—“When Color Matters” is our slogan!
Since you have already thought of your favorite color, now imagine if you couldn’t get products made in that color reliably. Imagine if you painted one room of your house in that color and loved it so much you decided to paint other rooms the same—but the paint store couldn’t give you more of the same color. They could get close—maybe—but it would still not match. Would that be acceptable? Most would probably say “NO!”
If color matters—than color tolerance matters as well. It’s not just a matter of how we color things, but how we achieve the same color again and again and again. So, what exactly is “color tolerance?” Simply put, it is the amount of allowable difference between a color reference and samples produced to match it. In other words, the most we will accept our trials being different than the target color we are making—that is our tolerance.
While it is not always an exact science, color tolerance can be measured. Because of the physics of color (unique wavelengths of light reflected and absorbed by objects), sophisticated instruments have been developed that are capable of “seeing” and measuring the “fingerprint” (spectral data) specific to each color evaluated. With this information, manufacturers work to replicate the color by formulating trials to match the color’s spectral data as closely as possible. With the most common color difference equations, the overall difference (or “distance”) between comparisons is calculated and defined by a term called Delta E (or DE). The smaller the DE value, the closer the compared colors are to being a match.
There is a psychophysical concept called “just-noticeable-difference” (or JND). It refers to the threshold at which an individual is capable of detecting a difference at least 50% of the time. Although individual observer’s color sensitivities may vary, the JND of visual color perception is generally around 1 DE. Because we place such a high importance on reliable repeatability of color, ICD’s color tolerance for OPACI-COAT-300® spandrel and wall cladding coatings is 0.20 DE—that is a tolerance 5 times tighter than the average person can detect!
Why go to such extremes? Many factors contribute to the ways one might detect a color difference—light sources and angles, substrates, surrounding features, foregrounds, backgrounds, etc. The closer we can get a color to a spectral match, the less affected it will be by other factors. “When Color Matters,” our customers can expect to receive the exact colors they need with every order—and that is how it should always be.
If we were that paint store, you’d get your favorite color every time—no question about it!
Post written by Jeff Nicholson, ICD High Performance Coatings Technical Service Manager