What Is Masterbatch And Why Is It Used?

Masterbatch is a concentrated blend of colorants, special effect pigments, and functional additives encapsulated within a carrier resin. Supplied mainly in pellet form, it’s mixed with raw polymers during plastic processing to deliver vibrant colors, unique finishes, and enhanced material properties. Nearly every colored plastic product you see around you—from packaging to automotive parts—is colored using masterbatch.

Advantages of Using Masterbatch

Using masterbatch in plastics manufacturing offers several benefits over liquid colors or powder blends:

• Cleaner production process: Pigments are pre-dispersed in resin pellets, reducing mess and contamination.

• Precise color control: Accurate dosing ensures consistent color throughout production.

• Lower downtime and waste: Improved efficiency helps cut production costs.

• Versatility: Masterbatch can deliver not only color but also functional enhancements, such as UV protection, flame retardancy, or anti-static properties.

Special effect masterbatches create finishes like metallic or pearlescent looks. Additive masterbatches can be combined with color masterbatches, allowing plastic molders to add performance features and color in one step—saving time and simplifying production.

Who Uses Masterbatch?

Masterbatch is used by:

• Plastic molders and extruders who incorporate masterbatch into polymer melts.

• Brand owners and packaging designers who work with masterbatch suppliers to create custom colors and effects.

• Product developers needing precise, repeatable color matching.

Companies like Broadway offer in-house color matching services, enabling direct collaboration between manufacturers and customers to approve and fine-tune final colors.

Applications of Masterbatch

Masterbatch is widely used in:

• Injection molding

• Blow molding

• Extrusion and profile extrusion

• Injection stretch blow molding (ISBM)

• 3D printing filaments

While rotationally molded items (like large tanks or kayaks) often use colored powders rather than masterbatch pellets, the vast majority of plastic parts in industries like packaging, automotive, consumer goods, and electronics rely on masterbatch.

How Masterbatch Works

Think of natural polymer as water and masterbatch as orange squash concentrate. A small amount of masterbatch—usually added at 1–5% by weight—colors or enhances the base material. For instance, a masterbatch formulated for a 1% addition rate can color around 99 parts of polymer.

During production, masterbatch is dosed into polymer using specialized feeders or simpler methods like tumble mixers. The blend melts in the extruder or molding machine, where pigments disperse evenly, delivering consistent color and properties to the final molded item.

How Is Masterbatch Made?

The masterbatch production process typically involves:

• Weighing and blending: Pigments, additives, carrier resin, and fillers (e.g., chalk) are measured and mixed.

• Extrusion: The mixture melts at around 180°C and is homogenized by an extruder screw.

• Cooling: The molten strands exit the die head and are cooled in water.

• Pelletizing: Solidified strands are cut into uniform pellets.

• Packaging: Finished pellets are bagged and distributed.

The carrier resin must be compatible with the polymer into which the masterbatch will be incorporated.

Using Masterbatch with Recycled Polymers

Masterbatch can be added to both virgin and recycled polymers. Recycled materials may have natural tint variations that slightly affect final color, but the environmental benefits of using recycled content often outweigh minor aesthetic differences. In packaging, including at least 30% post-consumer recycled (PCR) content can also qualify products for tax benefits in some markets, like the UK.

Experienced masterbatch suppliers can help adjust formulations to achieve desired colors and performance, even when using recycled resins.

NANJING HAISI is professional manufacturer of Plastic Extruder Machine, we supply Twin Screw Extruder, Single Screw Extruder, Plastic Recycling Extruder, Two Stage Extruder, Lab Scale Extruder, Mixing and Feeding Machine, Cooling and Pelletizing Machine, Crushing Machine and so on.