Composition, amphoteric polymeric flocculant and use of both

摘要: A composition which contains an amphoteric polymeric component comprising cationic monomer units, anionic and, if necessary, nonionic units as the constituent and exhibiting a 0.5 % salt viscosity of 10 to 120 mPa·s, wherein both first polymer satisfying relationship (1) second (2) or third relationships (3) (4) are contained component: Ca1/An1 ≥ 1 ... Ca2/An2 < Ca3/An3 |(Ca1 - An1) (Ca3 An3)| 1.5 [wherein Ca1 An1 respectively numbers calculated by assuming total number all be 100; Ca2 An2 Ca3 An3 similarly polymers respectively]. The exhibits excellent flocculation dewatering performances against various sludges, particularly even sludge having high surplus ratio, is also useful yield improver in papermaking.