What Is A Dye

What Is A Dye? A dye is a colored material that forms a chemical bond with the surface it is applied to. In contrast to pigments, which do not chemically bond to the material they color, this sets apart dyes. In order to improve the dye's fastness on the fiber, a mordant may be needed while applying the dye, which is typically done in an aqueous solution. Natural and Synthetic Dyes Natural and synthetic dyes fall into two major categories.  Natural dyes are those that are derived from plants, insects, or minerals. Vegetable dyes, which are typically obtained from plant materials such as roots, berries, bark, leaves, and wood as well as other biological sources, make up the majority of natural colors.  Because they are made from materials that, until recently, could only be extracted from coal tar, synthetic dyes are also known as coal tar dyes. A chromophore and an autochrome are combined with a benzene derivative to create a synthetic dye. Due to the fact that only some visible light wavelengths are absorbed by dyes and pigments, both are colored. Typically, pigments are insoluble in water but dyes are. With the addition of salt, some dyes can be made insoluble and transformed into lake pigments.

Types of Dyes Chemical characteristics and solubility are used to categorize dyes.  Acid dyes are water-soluble anionic dyes that are used in neutral to acid dye baths to color fabrics like silk, wool, nylon, and modified acrylic fibers. Anionic groups in the dyes and cationic groups in the fiber produce salts, which are thought to be at least partially responsible for attachment to the fiber. Cellulosic fibers are not significantly impacted by acid dyes. This group includes the majority of artificial food colors.  Basic dyes are cationic water-soluble dyes that are mostly used on acrylic fibers, though they can also be used on wool and silk. Acetic acid is typically added to the dye bath to aid in the dye's absorption onto the fiber. Paper coloring also involves the use of basic pigments.  Vat dyes can't directly stain fibers since they are essentially insoluble in water. The water-soluble alkali metal salt of the dye is created when alkaline liquor is reduced.  A chromophore linked to a substituent that can directly react with the fiber substrate is used in reactive dyes. Reactive dyes are among the most durable colors due to the covalent bonds that bind them to natural fibers. View more: https://www.globalchemmall.com/dyes