Hair dyes that are commercially sold have very complex formulas and the process of making it vary from one manufacturer to another. As a matter of fact, the same manufacturer may have their recipes different for dyes of different colors. Most hair dyes available are containing actual dye itself and a host of other ingredients such as soaps, antioxidants and chemicals which aid in the penetration of due, aromatic compounds that add fragrant, as well as other modifying compounds that can make the hair software or affect the permanence of the dye.
Most dye pigments are based on a type of molecule known as amino and it will often shop up on the list of ingredients as the name long named molecules with amino in them. Other dyes would use metal oxides like iron oxide for pigmentation.
Before using the ingredients, they are chemically tested beforehand to ensure that they are potent, pure and compound as what the label says. Also, the ingredients must be weight first, especially if large amount of ingredients are to be used. It should be kept in a huge storage tank from which the amount required for the process is piped in. The dye pigments are then dissolved in hot water after some of the other ingredients like antioxidants are incorporated in combined for around 20 minutes.
The primary mixture is added into another tank that contains the remaining ingredients. Depending on the batch size of the hair dye to be made, the pre-mix may be wheeled over manually or piped into a bigger tank. The process of mixing usually takes two to three hours and the fragrant compounds are incorporated to the end of the mixing process. Most of the dye that came out as results is packaged and labeled, though some samples are taken from every batch of the hair dye to ensure that it has been correctly made. This is also done to make sure that it is safe for people to use. By practicing these methods, the hair dye becomes suitable for use and could last longer, compared to homemade ones.