Carboxymethyl cellulose (CMC) is a cellulose derivative, which is a white, odorless, and tasteless powder that is derived from natural cellulose through a chemical process. It is a polysaccharide made up of repeating units of glucose, the sugar that makes up cellulose.

In the oil & gas industry, CMC is used as a viscosity-modifying agent in drilling fluids. It is added to drilling fluids to increase viscosity and gel strength, which to maintain the stability while drilling. CMC is also used to reduce the fluid loss of the drilling fluids, which help to maintain the integrity of the borehole walls and prevent the fluid from entering into the formation.

In the food industry, CMC is used as a thickening agent, emulsifier, and stabilizer to improve the texture and appearance of food products, such as ice cream, cheese, and sauces.

In the pharmaceutical industry, CMC is used as a binder, disintegrant, and lubricant in the production of tablets, capsules, and other solid dosage forms.

In the cosmetics industry, CMC is used as a thickening agent and emulsifier in the production of lotions, creams, and other personal care products.

In the construction industry, CMC is used as a lubricant and water-retention agent in the production of cement and concrete, as well as a viscosity-modifying agent in drilling fluids and as a binder in ceramics and refractories.

CMC is considered safe and non-toxic, and is approved for use as a food additive by many regulatory agencies worldwide. E number is E466.