A high-pressure self-cleaning mixing apparatus adapted to mix at least first and second reactive polyurethane-forming components and feed the mixed components to a mold is disclosed. The apparatus includes at least a mixing chamber, first and second feed passages, first and second recycle passages, and...http://www.google.com.au/patents/US6079867?utm_source=gb-gplus-sharePatent US6079867 - Self-cleaning, mixing apparatus and method for the production of polyurethane formulations
