Liquid color has been used in injection molding for years, but at Rotoplas, Reduction Engineering Scheer Inc. introduced an inline color mixer for use during pulverizing of powder for rotational molding.
The company in Kent, Ohio, also showed a newly designed pulverizer.
Reduction Engineering Scheer partnered with PolyOne Corp.’s Colormatrix unit to make the device. And the companies received a U.S. patent on the incolor mixer Oct. 8 during the trade show, according to Rick D’Angelo, chief operating officer of Reduction Engineering Scheer.
The liquid color is added at the beginning of the mixing process, after the powder comes out of the pulverizer, using a Colormatrix volumetric dosing controller and pump system.
The color mixer allows the molder to adjust color concentration during mixing. The unit gives faster cleanout and color changes that traditional dry pigments, and can reduce cost of color, according to the companies.
Laura Glascoe, Colormatrix’s director of product management, said the color mixer uses latent heat from the milled powder to flash off the liquid in the colorant.
At Rotoplas, Reduction Engineering Scheer linked the inline color mixer with one of its new RE Series of pulverizers, a new design with a smaller footprint than earlier models, and ease-of-use features. The sifters are stainless steel, not the traditional wood, and they have a larger number of decks, D’Angelo said.
The airflow is adjustable from the factory floor level, without the need for drives. The feed hopper also is accessible from the floor.
The RE line has a new adjustable air flow system. A high efficiency motor drives the pulverizing mill and the blower.
RE Series pulverizers come in three output sizes, ranging from 400 to 1,500 pounds an hour.