The two important sources of colorants are dyes and pigments. However, there are some differences in the characteristics, manner of use, benefits and weaknesses of each of them, although quite often the terms pigment, dye, colorant, tint, paint, color are incorrectly used interchangeably. .
Dyes come from organic and inorganic sources and dyes make up a large percentage of organic colorants while pigments come largely from inorganic sources. Natural pigments are obtained from animal, vegetable and mineral sources; however, most pigments are composed of inorganic oxides and salts such as chromium and iron oxides that diffuse in powder form in the application medium. Diffusion coloring properties are determined by the shape and size of the pigment particle. Dyes are divided into natural and synthetic dyes, where the natural sources of dyes are the same as pigments, while synthetic dyes are based on petroleum compounds.
Dyes and pigments are equally important to humans for providing color to all kinds of items, but the main difference between the two lies in their basic way of imparting color. In the case of dyes, the color diffuses at the molecular level since they are soluble in the organic solvent or in water, while in pigments the color diffuses as particles because they are insoluble in any type of liquid medium. Additional compounds are required to bind the pigment particles to the substrate. For example, paint pigments require the addition of polymer in the paint for diffusion.
The color vibrancy of dyes depends on the electronic properties of their chromophore molecule. Dyes colorants impart higher gloss and exhibit greater color strength as well as being simpler to process. Among dyes, basic dyes are best known for their vibrancy and brilliance and compatibility with anionic and synthetic materials. All basic dye manufacturers in India will confirm their suitability for dyeing cationic and synthetic items such as acrylics. However, dyes as colorants exhibit low durability, solvent and heat stability and high levels of migration and acid red is one of them, it is no different.
On the other hand, pigment colorants are more durable, solvent and heat stable, as well as being resistant to light and migration. But its cons include low intensity of color and brightness. Due to the markedly different characteristics of dyes and pigments, many efforts were made to improve the properties of each class of colorant. This led to the development of a new class of dye called Nanodyes.
This class strives to combine the good processability and superior color characteristics of colorants and the better durability of organic pigments. Combining the advantages of both colorants, nanocolorants have emerged as a better alternative and have shown superior characteristics that are very useful in various applications, such as the preparation of aqueous inkjet inks, high-performance colorfast polymer coloration, toners electrophotographic, among others.
In any case, regardless of the characteristics, dyes and pigments are essential elements to help us lead a life full of color.