Global Patent Index - EP 0816558 B1

EP 0816558 B1 20011205 - Process for increasing the degree of whiteness of paper making stock from recycled paper

Title (en)

Process for increasing the degree of whiteness of paper making stock from recycled paper

Title (de)

Verfahren zur Erhöhung des Weissgrades von aus Altpapier gewonnenem Papierfaserstoff

Title (fr)

Procédé d'amélioration du dégré de blancheur de pâte à papier à partir de papier recyclé

Publication

EP 0816558 B1 20011205 (DE)

Application

EP 97108991 A 19970604

Priority

DE 19626200 A 19960629

Abstract (en)

[origin: EP0816558A1] The whiteness of paper fibre, in an aqueous suspension containing at least 5% dry material, is increased by the use of oxidising bleaches, the bleaching action being further increased by molecular O2. The process takes place under excess pressure of at least 0.1 bar and the gas used contains 50% O2 at the most.

IPC 1-7

D21C 9/147

IPC 8 full level

D21C 9/147 (2006.01); D21C 9/16 (2006.01)

CPC (source: EP)

D21C 9/147 (2013.01); D21C 9/163 (2013.01)

Designated contracting state (EPC)

AT FR GB SE

DOCDB simple family (publication)

EP 0816558 A1 19980107; EP 0816558 B1 20011205; AT E210217 T1 20011215; CA 2208940 A1 19971229; DE 19626200 A1 19970515; DE 19626200 C2 20010201

DOCDB simple family (application)

EP 97108991 A 19970604; AT 97108991 T 19970604; CA 2208940 A 19970627; DE 19626200 A 19960629