Additives (Colorants)
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Pigment powders
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Dyes
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Carbon black
- Spray paint
Key risk: dispersion, abrasion, viscosity spikes, plate-outs
Colorants adds or modifies the colors of base polymer. In small screw extrusion like Materium, using liquid colorants will be harmful as they spill and colors everything on the feed path.
Dry colorants (like resin pigments) are usually organic materials that doesnt melt and most importantly, are flakes. Flakes are wide and thin, so inside a compression column, it will align itself parallel to walls (of barrel and screw) and plates them. If they stay is fine, but provlem is they break off little by little after consecutive extrusions so just purging them does not clear htem out entirely. You gotta disassemble and clean everything by scraping and heating,
Why Dry Powders Cause Plate-Out in Screw Extruders
Cover:
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Agglomeration vs miscibility
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Pigment plate-out
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Why chameleon / pearlescent pigments are worst
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Why masterbatch exists
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Why Materium is not a compounder