Without realising it, most people use wood-based cellulose every day. Toothpaste is one of the products that contain cellulose gum (CMC).
“Pulp is used for more widely than just to produce paper and board. It is also used to make CMC, a specialty ingredient which is used in several consumer products,” says Pirkko-Leena Hakkarainen, Product Development Director at Metsä Fibre.
CMC is a water-soluble cellulose derivative that binds raw materials into a smooth, easy-to-use product. It gives toothpaste its homogenous structure, easy flow, proper viscosity, and glossy appearance.
Whitening toothpaste and toothpaste for sensitive teeth contain different types of CMC. Another dental application of cellulose gum is fixtures. It is used in the adhesive that creates a perfect fit for false teeth.
CMC is a versatile ingredient
Nouryon, a global leader in specialty chemicals, manufactures CMC in Äänekoski, Finland. The company receives the key raw material, cellulose, directly from Metsä Fibre’s bioproduct mill. The production plants are located on the same site.
“CMC is a very versatile ingredient. It is used in condiments, bakery products, protein drinks, yoghurts, laundry detergents, eye drops, ice packs, wine refining, veterinary medicine, oil drilling and hundreds of other applications,” says Yogesh Solanki, Technical Development Manager at Nouryon.
CMC is produced in two stages. In the first step, cellulose is suspended in an alkaline solution, which opens the cellulose structure and allows the next reaction to happen.
“In the second stage the cellulose can react with sodium monochloroacetate to yield sodium carboxymethyl cellulose,” Solanki explains.
Far from a bulk product
Today, CMC comes in three different main types. Technical CMC is for industrial applications. Purified, low-salt CMC is used in paper and board production. Highly purified CMC is for food and other consumer products.
In regulated industries, legislation and testing can take several years so gaining approval is a costly process. Every ingredient must be of the highest quality.
CMC is far from a bulk product, as Hakkarainen notes.
“Rather, it is a large collection of different grades that all have unique uses and functionality. Nordic wood based high-quality pulp offers a good basis for many modern CMC product types, and for future developments in this area.”
This article was originally published in Fibre Magazine issue 2022–2023.