Instead of extruding a colored cap layer onto sheet, profiles, or film, certain clear and opaque polymers can be dyed in a water bath, infusing color about 0.01 in. into the polymer and using a fraction as much colorant as would be used in melt compounding.

Instead of extruding a colored cap layer onto sheet, profiles, or film, certain clear and opaque polymers can be dyed in a water bath, infusing color about 0.01 in. into the polymer and using a fraction as much colorant as would be used in melt compounding. Because the process colors natural resin after melt processing, it is suited to short runs and quick changes with no need to purge the extruder. The patented system, called Aura Infusion Technology, has been available for licensing from Bayer MaterialScience LLC, Pittsburgh, since 2002. Up to now, it has been used mainly for molded parts, though Replex Plastics in Mt. Vernon, Ohio, developed a tank immersion system for profiles, reportedly capable of 60-sec color changes. New approaches are being developed for coloring extruded (and molded) products by custom automation integrator Radco Industries Inc., Toledo, Ohio. It recently established an Infusion Technologies Div. to supply custom equipment for the Aura process to processors licensed by Bayer. Radco developed an immersion process to color cut sheets of PC or acrylic off-line. It is also developing a pilot system to dye film in a roll-to-roll process. The advantage is reduced product inventory, since sheet or film can be dyed to order. Aura dyes work with amorphous polymers like acrylics, PC, ABS, TPU, EVA, nylon, PET, and PETG, but can’t color highly crystalline or crosslinked polymers like polyolefins or PTFE. Bayer has also developed technology to infuse UV protection into the surface of PC sheet. (412) 777-2000 • www.bayerfantasia.com (419) 531-4731 • www.radcoindustries.com

Bayer MaterialScience
100 Bayer Rd. Pittsburgh, PA 15205-9741
Phone (412) 777-2000 Fax (412) 777-4478