Process and device for producing plastic moldings from a flowable reaction mixture

• Main Authors: RAFFEL REINER, DUSCHANEK HELMUT, SULZBACH HANS-MICHAEL
• Format: Patent
• Language: English
• Published: 21.10.2003
• Edition: 7
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; MAKING GRANULES OR PREFORMS; MIXING, e.g. DISSOLVING, EMULSIFYING, DISPERSING; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PREPARATION OR PRETREATMENT OF THE MATERIAL TO BESHAPED; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIALCONTAINING PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

Polyurethane molded articles are produced from a flowable polyol-polyisocyanate reaction mixture on a shot-wise basis. The flowable reaction mixture is formed by combining the components of that mixture in the mixing chamber of a mixhead. The contents of the mixhead are introduced (preferably via an outlet pipe) into a mold in a manner such that the mixing chamber is substantially emptied in each case. Any ambient gas in the mixing chamber is then removed before the respective next shot is initiated.