DEFOAMING AGENT, METHOD FOR PRODUCING PAPER AND METHOD FOR CLARIFYING WASTE WATER USING THE SAME

• Main Authors: YASUMOTO MAYUMI, TANAKA TAKASHI
• Format: Patent
• Language: English
• Published: 02.08.2012
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; IMPREGNATING OR COATING OF PAPER; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PAPER NOT OTHERWISE PROVIDED FOR; PAPER-MAKING; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; PRODUCTION OF CELLULOSE; PULP COMPOSITIONS; SEPARATION; TEXTILES; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE

PROBLEM TO BE SOLVED: To provide a defoaming agent which exhibits an excellent foam inhibition effect and an excellent defoaming effect even at low concentration and further to provide a method for producing paper and a method for clarifying waste water using the defoaming agent.SOLUTION: The defoaming agent contains an oligoester compound shown by following formula (1), wherein Rmay be the same or different and shows a residual group formed by removing two hydroxyl groups from a polyol compound, respectively, Rshows a residual group formed by removing a carboxyl group from a dicarboxylic acid, Rand Rmay be the same or different and shows a residual group formed by removing a hydroxyl group from a carboxyl group of 8-36C high fatty acid, respectively. However Rand Rare not be hydrogen atoms at the same time, n denotes an integer of 1 or more and when n is 2 or more, Rand Rmay be the same or different from each other.