Masterbatch is a liquid or solid additive for plastics used for colouring plastics commonly known as a colour masterbatch or imparting other properties to plastics referred as an additive masterbatch. Alternatively, a masterbatch can be defined as a concentrated mixture of additives and/or pigments encased, to ensure better dispersion, homogeneous compound and minimized batch to batch variation of the critical material, during a heat process into a carrier resin that is cooled after and sliced into a granular shape.
Masterbatch carrier material can be based on a universal carrier such as wax or a specific polymer, compatible with the natural polymer or even identical- polymer specific. Such as LDPE can be used as a carrier on nylons and polyolefins, polystyrene can be used for ABS. This is done to avoid modification of the resultant plastic properties. Similarly, the specification of the resin is very vital. The concentration of the additive in the masterbatch is much higher than in the final polymer, but the additive is already properly dispersed in the host resin. Their use is an analogue of uses of ferroalloy for adding alloying elements to steel.
The colour masterbatch consists of pigments or dyes, carriers composed of; uniform pigment or dye evenly attached to the resin obtained in the aggregate to make the tinting higher than the pigment itself. Simply a colour masterbatch is an aggregate made by adding ultra-constant pigments or dyes to the resin. In addition to adding colour, other properties can be incorporated into the masterbatch; such as antimicrobials, UV stabilizers, anti-statics, fire retardants, antioxidants, fragrances.
Masterbatch is ideally designed to suit a wide range of polymers. Since the pigments in the masterbatch are not bio-available, their product is a health and safety proposition as the pigment can become airborne during manufacturing processes, potentially contaminating adjacent manufacturing lines. Since they are in pre-mixed compositions, their use eliminates the issues with the additive or colorant insufficient dispersion or dispersion. It also offers better colour consistency of products from lot to lot, and even within lots than raw pigment. It is simpler to feed and handle colour concentrates during the manufacturing process when masterbatch is used.
