The Science Behind: Paint (Part 1)

When I’m painting, the last thing I’m thinking about is how my paint is made, what it’s made from, etc. etc. But the paint we use goes through an extraordinary journey and fascinating scientific processes to become the beautifully pigmented medium it is, and it’s worth reading about!

As some of you may know there’s a multitude of types of paints out there. There’s paint that is specifically used for the interior of your house, the exterior of your house, wood, glass, plastic, and other surfaces, paint for arts and crafts: acrylic, watercolor, gouache, oil paint, tempera, and more. For simplicity’s sake, in today’s article we’re going to be focusing on artist’s paints.

Though the processes used to make artist's paints, and even some of the ingredients needed to do so, resemble each other quite a bit, there are also a few varying details. In this article, I will be focusing on the ingredients. And in the next part, I will go into more detail about the processes.

For each of these paints, a powder pigment, a binder, and a vehicle, which is essentially “a part of the paint that carries the pigment and binder,” are required.

Most of the time the pigments used in oil, acrylic, and water paints are synthetic, meaning they are contrived from coal tars and petrochemicals, which are toxic for the environment. Very rarely are organic pigments used, which is why paint is harmful to our planet and has to be disposed of in a special way.

The binder differs from paint type to paint type. In acrylics, polymer is most commonly used. For oils, refined linseed oils, and watercolor, either gum arabic and synthetic glycol can be used. The type of binder and the amount used is usually what determines the consistency of the paint and how it is used. For example, linseed oil, used in oil paints, is quite thick, which is why oil paints usually parallel more of a paste than liquid. Gum arabic in watercolors, on the other hand, is very soluble in water, which explains how water colors are able to dissolve easily when dipped into water.

And lastly, we have the vehicle of the paint. The vehicle, depending on the paint, can be considered a part of the binder or a consecutive of it. In acrylics, water is generally used. As an acrylic painter, I fully understand how this comes to be. Acrylic usually dries in a matter of minutes (which is a blessing and a curse at the same time!), which is because the water in the paint solution doesn’t take long to dry. Oil paint and watercolor don’t have a vehicle; their binders (linseed oil and gum arabic) do the job of both. Like I said, it depends on the type of paint.

And these are the main three components that are used to make artist’s paints! Of course these aren’t the only 3 components; there are many, many other solutions that are added in different amounts and forms to make these paints.

I do hope this article gave you a nice overview though and helped you learn something new! Stay tuned for part 2!