| abstract |
A method of improving surface strength, fibre tear or linting of a sheet-formed fibrous material formed from an aqueous slurry of cellulose fibre comprising spraying a face of the material with a chemical formulation comprising or consisting of a polymer containing at least two carboxylic groups per molecule and aliphatic mono-di- or three- basic carboxylic acid with molecular weight between 40-500Da, in an aqueous carrier, keeping the coated face at a temperature of 50 ยบ C or more for a time sufficient to obtain the desired improvement including drying of the material. The chemical formulation is sprayed on the wet laid sheet-formed material at the wet end of a paper machine in an amount of from 1% to 5% by weight of the sheet-formed material in a dry state. Also disclosed is a sheet-formed fibrous material obtainable or obtained by the method and a laminated product comprising the sheet-formed fibrous material and a polymer foil. Further disclosed is the use of the chemical formulation for improving surface strength, fibre tear or linting of a sheet-formed fibrous material. |