July 07, 2022

What Is a Pigment? What Are Its Types?

A pigment is a material that creates a color change by absorbing light reflected from or transmitted through it at different wavelengths. In other words, the material reveals its color by emitting the absorbed light energy at a specific wavelength. Since these emissions can physically occur in the forms of fluorescence, phosphorescence, and other luminescence types, different color characteristics emerge depending on the pigment. For example, thanks to the chlorophyll pigment found in a leaf, sunlight with all wavelengths hitting the leaf is reflected only in the wavelength of green light, causing the leaf to appear green.

Many materials on Earth create color by emitting different types of light. However, some are classified separately by humans and called pigments due to their coloring properties. In addition to having their own unique colors, pigments are also expected to have strong coloring capabilities. When mixed with other materials, their ability to determine the color tone defines their quality. A pigment is expected to provide a permanent and stable coloring effect. The loss of color over time or under light exposure is called fading. When autumn arrives, due to insufficient sunlight compared to summer and the weakening of chlorophyll pigment in leaves, the yellow pigment (carotenoid), which is already present but weaker than chlorophyll, becomes dominant, causing the leaf to turn yellow. Since the desired color is green, this is referred to as fading. Therefore, pigments are substances affected by their environment.

Pigments are used as colorants in many industries. They are used as additives in sectors such as cosmetics, plastics, ink, and food to achieve the desired color in the final product. They are generally produced in solid powder form and can be organic or synthetic.

In the plastics industry, pigments can be directly added as colorants during production, but due to the advantages they provide, they are more commonly preferred in the form of masterbatch.

As is known, different wavelengths of light in nature produce different colors. Pigments are materials that reflect or transmit incoming light at selected wavelengths. Since each pigment reflects light at different wavelengths, they produce their own unique colors. Pigments, usually found in powder form, are used in industry to color other products. The two most important properties expected from a pigment are high coloring strength and long-term stability, meaning the ability to retain its color over time.

Organic pigments are pigments that contain carbon in their structure. They are generally obtained synthetically and are rarely found in nature. In contrast, inorganic pigments do not contain carbon atoms and are mostly obtained naturally (from minerals, etc.). In terms of properties, organic and inorganic pigments differ from each other.