Dispersion;A&G New Material Manufacturing Corporation

Excellent pigment dispersion in the final product is essential to its performance. Defects caused by non-dispersed pigment particles (specs) can result in a severely lowered performance level. With good dispersion of pigments the following problems can be avoided:

color inconsistency, loss in color yield, batch-to-batch shade deviation ,
Negative effects to the physical and mechanical properties of the final product such as loss of electrical proporties in wire & cable applications,
Negative processing effects such as filter blockage, breakage of the fibre or undesired splitting of the blown films,
...

The combination of optimized processing conditions, pigment selection, and dispersing agent can help you achieve good dispersion and avoid some of the problems listed above.

The more finely the pigment is dispersed (smaller average particle size), the larger the total surface area of the pigment particles and the greater its colour strength (see figure 1).

In some cases, dispersion of organic pigments is quite difficult to achieve. The use of predispersed pigments is recommended when coloring engineering plastics and for some PVC applications. They offer greater shade consistency and reproducibility. They remain unaffected by agglomeration by high shear high speed mixers during dry-blending, and have higher colour strength (at representative comparable concentrations), purity and transparency.

Source from: www.spcialchem.com