Paint it Black (with Chalkboard Paint)

This week, I made my biggest (and let’s be honest: first real) design decision ever: I painted an entire wall in my home black. Black as in chalkboard paint. I know I’m several years behind the wagon on this, but this paint is the decorating equivalent of a Little Black Dress for your wall. I’m a little obsessed.

But it’s a weird paint, too: if you’ve used it already, you’ll know it’s matte, textured to the touch and up close, it’s crackled like fine snakeskin even three coats thick. As it turns out, it’s packed with the same things you find in sunscreen, nail polish, car tires, and Egyptian pyramids. As an homage to my new favorite wall — and to one of my favorite Wired columns — here’s a breakdown of some of the key elements:

Carbon Black. Carbon black is the most important color additive here. It’s the black, almost sooty material you get from partially combusted hydrocarbons, not entirely unlike what you get from charred materials. In its pure form, it’s about the blackest black you can get, reflecting almost no visible light. It’s also a reinforcing agent that pops up in car tires, printer ink, and various other rubbery products (belts, hoses, wiper blades, and bumpers), and is easily one of the most common and essential industrial chemicals in the world. Globally, we go through billions of pounds of the stuff every year.

Limestone. The Egyptian pyramids are made out of limestone, and chances are, so is your toothpaste, at least partially. Limestone’s a relatively porous, sedimentary stone that acts as a critical ingredient in cement, a popular filler in paints, and an excellent source of calcium.

Potassium Aluminosilicate. Also known as mica. It’s a lovely, metallic/opalescent mineral with (for a rock) exceptional flexibility and a tendency to split off into incredibly useful, flame-resistant, insulating sheets. It also pops up regularly in paints and cement, where it helps with the viscosity, mixing and aesthetically appealing luster.

Ester Alcohol. This is a double whammy of a chemical that helps the paint dry smoothly and quickly (my first coat felt dry to the touch in 15 minutes) and it makes it more cleanable after it is dry and I’ve started messing around with it (which, this being a chalkboard wall for writing, I plan on doing). For similar reasons, it also shows up in nail polish.

Titanium Dioxide. Yes, as in sunscreen, the stuff we should all smear on our faces every day. It also happens to be an extremely common paint ingredient. It helps with opacity and gloss while playing a role in pigment. Sitting on the far side of the spectrum opposite carbon black, titanium dioxide is an incredibly refractive material. In a black paint, it won’t be the dominate color, but it does play a part in balancing the color: making the wall (thank god) not a pure, charred, light-sucking black. On an unrelated note, titanium dioxide can also be used to improve the skim milk drinking experience.)