Paint & Coatings Industry - March 2008 - (Page 69)

Dispersion Process Production designed for tests and the production of small batches, a safe scale-up to the production machine guarantees a high degree of safety and flexibility. Figure 3 | Comparison of common systems. Comparison of Different Dispersion Methods For highly viscous products, there are low-speed systems like butterfly mixers and high-speed mixers with finely toothed discs based on cavitations (cavitations disk). These systems are used to wet out dry particles with liquid components, but no defined measurement can describe their efficiency factor. A method described as sub-level feeding shows energy savings. The wetting process, as such, cruises as a black box with the pseudonym dispersing process, which defines only the quality of the result. The future may find a new definition such as coating- or wettingprocess of micro powders. When comparing the variety of different dispersing systems, relevant literature does not support production parameters. Equations mainly support mechanic layout of mixing systems to determine power requirements. The field of efficiency linked to the applications and information about specific energy remain undefined. Figure 3 shows the most common system groups with saw disks and butterfly tools in comparison to the Ψ-MIX, specified by installed power, which seems to be an indication for installation and running costs. The energy input on the Ψ-MIX relates only to the powder feeding time. The volumetric dosing rate of up to 5 m³/h, together with the bulk density of the dry components, results in the batch time. Additional rework, in most cases, is not necessary. Most methods are based on producing wet agglomerates, which should be broken apart by mechanical energy input via rotation. One of the problems with conventional technology is the broad size distribution of the agglomerated particles initially produced by the wetting process, from 10 microns (µm) to 2.0 mm and more. The request for more dust-free and process-reliable powder handling leads to granulated and palletized raw materials, which is not supporting the basics of wetting micronized primary particles. Figure 4 | Dry agglomeration distribution. Figure 5 | Comparison of conventional mixing systems to the Ψ-MIX. PA I N T & C O A T I N G S I N D U S T R Y 69

Table of Contents Feed for the Digital Edition of Paint & Coatings Industry - March 2008

Viewpoint Industry News Calendar of Events Company News Mergers and Acquisitions Names in the News Marketplace Quarterly Stock Watch Reaching Strict VOC Requirements With Outstanding Durability for Industrial Maintenance and Marine Coatings A Unique Fungicide for Wood-Filled Plastic deSigns of the Times: Slacking Off! From Rocks to Nanos Shear-Free Dispersion Process Fluorinated Oxetane Oligomers as Versatile Intermediates for Polymer Modification The Effects of TPO Composition on Adhesion and Proposed Chemical Mechanism Supplier Showcase Color Management Materials Watch Products Classifieds Advertiser Index

Paint & Coatings Industry - March 2008

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