Key Role in Pigment Processing

A Malvern Mastersizer laser diffraction particle size analyser is playing an important role in the development and evaluation of specialty mixing systems at the Test & Development Center of Charles Ross & Son Company, New York. The company’s PreMax mixer with Delta rotor/stator improves pigment dispersion ahead of media milling operations in the production of inks and coatings. Both the developers and users of the PreMax employ the Mastersizer to track pigment dispersion as mixing progresses, allowing optimisation of PreMax operation for different applications and process conditions.

Despite huge advances in the formulation of pigment-based inks and coatings, production invariably remains a two-stage process, with the pigment being wetted out to produce the pre-mix, which is then milled to the required particle size.

“Typically the focus at the premixing stage is simply to achieve adequate wetting of the dry pigment,” said Christine Banaszek, Application Engineer at Charles Ross & Son Company. “We wanted to develop a more efficient solution that also reduces agglomerates of particles, in order to cut milling time. The Delta rotor/stator of the PreMax provides both high shear and vigorous flow in a batch mixing environment. Clearly particle size analysis was essential in evaluating our results, and the Mastersizer proved an excellent choice. Quick and easy to use, it enabled us, and our customers, to measure material at all stages of the process, and fully test the PreMax’s performance.”

The Mastersizer is a laser diffraction system for the rapid measurement of dry or wet particles. While the system itself offers versatility, a broad measurement range, reproducible sample dispersion and measurement, it is Malvern’s applications expertise, which really sets it apart. “Malvern has pioneered laser diffraction for more than three decades,” said Paul Kippax, Product Manager at Malvern Instruments. “The extensive knowledge and applications experience we have in this area comes not only from the scientific credentials of our in-house experts, but is also fostered through our strong relationships with customers such as Charles Ross & Son
Company. Such relationships enable us to gain an even greater understanding of our customers’ needs and how to excel in meeting them, and has fuelled the success of the Mastersizer range.”