Patent ID: 7988821

Claim:
A process for the treatment of a fibre material comprising contacting the fibre material in an aqueous medium with a chelating agent and a single polymer having the following general formula wherein R 1 is a hydrogen atom or an alkyl group containing 1 to 12 carbon atoms, R 2 is —COOM or —CH 2 COOM, M is a hydrogen atom, an alkali metal ion, an alkaline earth metal ion, an ammonium ion or a mixture thereof, n, m and k are molar ratios of corresponding monomers, wherein n is 0 to 0.95, m is 0.05 to 0.9, and k is 0 to 0.8, and (n+m+k) equals 1, and the weight average molecular weight is between 500 and 20,000,000 g/mol; and wherein the fibre material is a cellulosic fibre material comprising a chemical, mechanical or chemi-mechanical pulp or a recycled fibre material; and wherein the weight ratio of the polymer to the chelating agent is from 1:4 to 4:1.