Advantages: Inexpensive in small quantities and relatively easy to blend, do not require sophisticated equipment to load and may be used in a wide variety of resins (check with tech support.) The best way to custom color rotationaly molded parts.
Disadvantages: The difficulty to disperse most pigments and additives will yield inconsistent results. Airborne dust can cause contamination; required cleanup for hoppers, dryers and feeders. Do not use in desiccant dryers.
Advantages: Can be quickly manufactured resulting in lower cost and shorter lead times. Excellent dispersion can be achieved. Translucent containers simplify inventory control. Liquid color may be used in a variety of resin systems (check with lab.) Color intensity or incorporation of additives can be varied. Color changes can be done quickly. Certain special effects may be obtained. Base colors and additives may be mixed on site. Many chemical additives for polymers are liquid in their primary form making “single package” systems of pigments, additives and modifiers possible.
Disadvantages: Special equipment such as peristaltic or piston pumps are required to introduce the color into the process effectively. A pre-mixer, or dispersion device may be required to provide good dispersion. Liquid color can, however, be mixed in a drum tumbler or a low to high intensity mixer. Personal must be trained to handle and clean liquid efficiently. High loadings can cause screw slippage.
A non-dusting solid beaded particle approximately one half the size of a concentrate pellet. The standard bead formulation is made with waxes designed to work in wide variety of resins. Formulations using combinations of polymers and waxes or formulations for specific resin systems are available.
Advantages: Non-dusting particles are designed to be incorporated with color feeding systems, although tumbling or hand mixing can be used. Cleanup is easier than dry color. Cost of coloring small batches is more economical than concentrate. High pigment and additive loadings can be achieved (60%-100%) making large volumes of certain formulations very competitive with other systems. Lead times are generally shorter than concentrate. Blends of pigments and additives are possible. Beads do not have to be dried when incorporating into hydroscopic resins.
Disadvantages: Dispersions are better than dry color, but not as good as liquid or concentrate. Not recommended for vacuum loading or desiccant dryers. Wax beads will fracture or break apart in hoses or equipment causing a clean up problem. Higher loadings may cause over lubrication and screw slippage.
Colorants are dispersed in specific resins and extruded into pellets. Resin systems can be colored, modified, alloyed, and filled
Advantages of Concentrate: Easiest of all forms of colorant to handle. Better dispersions results in better color economy and additive consistency. Extremely fine dispersions (for film, fiber, bottles) can be achieved. “Single package” combinations of colorants, additives, and modifiers are possible.
Disadvantages of Concentrate: Longer lead times require careful material planning. Smaller quantities tend to be less economical. Concentrate is generally “resin specific.”